Tag: Life Sciences

Prof. Ehud Gazit – First Israeli to Receive Prestigious International Recognition in Chemistry

Selected as International Solvay Chair in Chemistry for 2023.

Prof. Ehud Gazit from The Shmunis School of Biomedicine and Cancer Research at The George S. Wise Faculty of Life Sciences and The Department of Materials Science and Engineering at The Iby and Aladar Fleischman Faculty of Engineering, was selected as the International Solvay Chair in Chemistry for 2023. Prof. Gazit, who also heads TAU’s Blavatnik Center for Drug Discovery, is the first Israeli to receive this annually awarded honor and the first scientist to be appointed to the position outside of the United States and Europe. 

 Joining 15 Other World Top Scientists

The Solvay International Institute was founded in Belgium about a century ago and is designed to develop and support creative and groundbreaking research in physics, chemistry and related fields, in order to increase and deepen the understanding of natural phenomena. The Institute organizes annual conferences on physics and chemistry, as well as international workshops for the training of doctoral students and selected topics. 

As part of Gazit’s new appointment, he will spend a month or two in Brussels, the capital of Belgium, during which he will give lectures on his field of research. The prestigious nomination has previously been awarded to 15 of the world’s top scientists, including three Nobel laureates in chemistry, the Wolf Prize winner and laureates of other prestigious awards, all from leading institutions in the US and Europe, who are now joined by Gazit. 

Gazit is a biophysicist, biochemist and nanotechnologist. His main area of expertise is “Solid State Biology”, an innovative field of study that combines disciplines from physics, chemistry, synthetic and structural biology and materials engineering. He is a world-renowned expert in nanotechnology and biological chemistry, a highly cited researcher who has published more than 350 scientific articles and inventor of more than 100 patents.

Previously, he served as Vice President for Research and Development of the University, as the Chairman of Ramot, Tel Aviv University’s Tech Transfer Company, and as the Chief Scientist of Israel’s Ministry of Science and Technology. 

Over the years, Gazit has won a number of prestigious awards and prizes in Israel and around the world, including The Kadar Family Award for Outstanding Research, the Landau Prize in Science and Arts and the Rapaport Prize for Excellence in Biomedical Research. He is a Fellow of the Royal Society of Chemistry in the UK, a Foreign Fellow of the National Academy of Sciences in India and a Member of the European Organization for Molecular Biology.  

Gazit stated: “I thank the Solvay Institute for selecting me, a great honor and excitement for me. It is a great privilege for me to join such a prestigious and impressive list of leading researchers. Today I am reminded of the former President of Israel, Prof. Ephraim Katzir, one of Israel’s greatest scientists, and of whom I am one of his academic ‘great grandchildren’ and who organized the Solvay Institute’s Chemistry Conference about 40 years ago. Apart from the personal honor, I am happy and proud to represent Tel Aviv University and the State of Israel in this appointment.”

How are the Birds Coping with Climate Change?

Researchers detect changes in birds’ bodies, probably caused by global warming.

Researchers at Tel Aviv University have found changes in the morphology of many birds in Israel over the past 70 years, which they interpret to be a response to climate change. The body mass of some species decreased, while in others body length increased – in both cases increasing the ratio between surface area and volume. The researchers contend that these are strategies to facilitate heat loss to the environment: “The birds evidently changed in response to the changing climate. However, this solution may not be fully adequate, especially as temperatures continue to rise.”

Relying on the vast bird collection preserved by The Steinhardt Museum of Natural History at TAU, the researchers looked for changes in bird morphology over the past 70 years in Israel. They examined approximately 8,000 adult specimens of 106 different species – including migratory birds that annually pass through Israel (such as the common chiffchaff, white stork, and black buzzard), resident wild birds (like the Eurasian jay, Eurasian eagle-owl, and rock partridge), and commensal birds, that live near humans. They built a complex statistical model consisting of various parameters to assess morphological changes – in the birds’ body mass, body length and wing length – during the relevant period.

The study was led by Prof. Shai Meiri and PhD student Shahar Dubiner of the School of Zoology, The George S. Wise Faculty of Life Sciences, and the Steinhardt Museum of Natural History at Tel Aviv University. The paper was published in the scientific journal Global Ecology and Biogeography.

Cooling Down

Prof. Meiri explains that according to Bergmann’s rule, formulated in the 19th century, members of bird and mammal species living in a cold climate tend to be larger than members of the same species living in a warmer climate. This is because the ratio of surface area to volume is higher in smaller animals, permitting more heat loss (an advantage in warm regions), and lower in larger bodies, minimizing heat loss (a benefit in colder climates). Based on this rule, scientists have recently predicted that global warming will lead to a reduction in animal size, with a possible exception: birds living in the human environment (such as pigeons, house sparrows, and the hooded crow) may gain size due to increased food availability, a phenomenon already witnessed in mammals such as jackals and wolves.

Either Long or Slender

Shahar Dubiner: “Our findings revealed a complicated picture. We identified two different types of morphological changes: some species had become lighter – their mass had decreased while their body length remained unchanged; while others had become longer – their body length had increased, while their mass remained unchanged. These together represent more than half of the species examined, but there was practically no overlap between the two groups – almost none of the birds had become both lighter and longer. We think that these are two different strategies for coping with the same problem, namely the rising temperatures. In both cases, the surface area to volume ratio is increased (by either increasing the numerator or reducing the denominator) – which helps the body lose heat to its environment. The opposite, namely a decrease in this ratio, was not observed in any of the species.”

 

The researchers (from left to right): Shahar Dubiner and Prof. Shai Meiri

Global Phenomenon

Sadly, flying away from global warming is not an option. These findings were observed across the country, regardless of nutrition, and in all types of species: resident birds; commensal species living in the human environment – which, contrary to predictions, exhibited changes similar to those of other birds; and migrants.

A difference was identified, however, between the two strategies: changes in body length tended to occur more in migrants, while changes in body mass were more typical of non-migratory birds. The very fact that such changes were found in migratory birds coming from Asia, Europe, and Africa, suggests that we are witnessing a global phenomenon.

The study also found that the impact of climate change over time on bird morphology (the birds’ change in either weight or length over time, relative to the actual temperature change during that time) is ten times greater than the impact of similar differences in temperature between geographical areas (the birds’ differences in weight or length in different geographical areas, relative to the temperature differences between those areas).

What is the Limit of Evolutionary Flexibility?

Shahar Dubiner: “Our findings indicate that global warming causes fast and significant changes in bird morphology. But what are the implications of these changes? Should we be concerned? Is this a problem, or rather an encouraging ability to adapt to a changing environment? Such morphological changes over a few decades probably do not represent an evolutionary adaptation, but rather certain phenotypic flexibility exhibited by the birds. We are concerned that over such a short period of time, there is a limit to the flexibility or evolutionary potential of these traits, and the birds might run out of effective solutions as temperatures continue to rise.”

Featured image: Israeli birds have become either longer or slenderer over the past 70 years

Inventive Study to Develop Biological Solutions for Agriculture

TAU and ag-biotech company PlantArcBio to collaborate on development of RNAi-based products.

Genetically improved plants can be a real-life magic stick for solving global famine issues. In a first-of-its-kind study, Ramot, the Technology Transfer Company of Tel Aviv University will cooperate with ag-biotech company PlantArcBio to develop innovative RNAi-based biological solutions for agriculture.

RNAi technology enables a temporary external disruption of RNA (ribonucleic acid) molecules, diminishing the amount of Messenger RNA (mRNA), thus temporarily reducing the expression of specific genes, without modifying or genetically engineering the organism’s DNA. Externally applied RNAi molecules affect specific genes for a specific time period, as required for positive effects like crop protection and yield enhancement. 

Specifically, the research will focus on testing the joint technology’s contribution to the stability of RNAi-based products and their ability to penetrate plants and insects.

Joining Forces

The first-of-its-kind joint study will examine the efficacy of PlantArcBio‘s RNAi technology for agriculture, combined with the unique lipid-based RNA delivery technology developed by Prof. Dan Peer, TAU’s Vice President for R&D, head of the Center for Translational Medicine and a member of both the Shmunis School of Biomedicine and Cancer ResearchGeorge S. Wise Faculty of Life Sciences, and the Center for Nanoscience and Nanotechnology, and a pioneer using RNA to manipulate cells in cancer and other immune related diseases.  

 

Prof. Dan Peer

“We see great value in contributing to the development of RNAi-based products addressing global issues and providing an ecological and environmentally friendly solution to the global challenges of sustainability in agriculture and food security,” says Peer.

Keren Primor Cohen, CEO of Ramot, believes there is “extensive commercial potential for this combined technology” and welcomes the collaboration with PlantArcBio.

The research will be carried out both at PlantArcBio‘s Laboratories and at Prof. Dan Peer’s Laboratory of Precision NanoMedicine at Tel Aviv University. According to Dror Shalitin, Founder and CEO of PlantArcBio, the results are expected within approximately 12 months.

Reading Tea Leaves

What is the origin of tea, and does the climate crisis threaten its production?

Tea – the ancient beverage comes in different flavors and colors. The Queen of England will never go without her afternoon tea, in India it’s enjoyed with milk and spices and we all like to pour ourselves an occasional cup of Earl Grey, especially when winter comes knocking. But have you ever wondered whether the saying “all the tea in China” really does indicate where tea drinking started? Or if the soothing drink may be affected by the climate crisis? Should we, in fact, be drinking it? We have, and our researchers explained, surprised us and busted some myths in the process.

When the Chinese Mystics Met the Tea Plant

We’re not going to keep you in suspense: It turns out that the coveted drink was sipped by the Indian Buddhist monks two thousand years ago – long before it became an integral part of Chinese culture and a long, long time before it became popular in Western cultures.

“The tea plant was known in China as early as the first centuries BCE, but recent studies show that the custom of drinking tea was brought to China from India,” explains Prof. Meir Shahar from The Department of East Asian Studies of The Lester and Sally Entin Faculty of Humanities at Tel Aviv University, who researches, among other things, the influence of Indian culture on Chinese religion and literature.

“In the first centuries CE Buddhism came to China from India and the Buddhist monks, who wanted to stay awake during the meditation, used to drink tea. The Chinese monks would observe this, and went on to adopt the custom as well, which then continued to spread to the rest of the Chinese population.”

While tea originates from India, the origin of the word ‘tea’ in most of the world’s languages, however, is Chinese. “In northern China it is called cha, hence the Russian chai, and in southern China it is pronounced as tcha, which is the origin of the English word tea,” reveals Prof. Shahar.

Buddhist monks on their tea break

What’s in Your Cuppa?

Buddhist monks realized long ago that tea keeps them awake and today, thanks to science, we are able to explain how the active ingredients of the plant affect us.

“Contrary to many people’s beliefs, all types of tea are produced from the same plant, namely the leaves and buds of the Camellia Sinensis plant. While there are several varieties of the plant, the types of tea that we are familiar with – white, green, oolong and black – differ according to the part of the plant from which they are produced and the way they’re processed. Green tea, for example, contains less caffeine than black tea. The leaves used to produce green tea undergo a minimal drying process while the leaves intended for black tea undergo drying and fermentation,” explains Guy Shalmon, a sports nutritionist and exercise physiologist at the Sylvan Adams Sports Institute.

“Tea leaves contain substances known as flavonoids. Their composition, however, varies from one tea to another. For example, green tea has a higher concentration of a substance called epigallocatechin 3-gallate, known for short as ‘EGCG’, than black tea which undergoes a prolonged processing process. It has antioxidant activity and is attributed various health effects,” says Guy.

“Having said that, tea may reduce the absorption of iron-derived iron minerals. The polyphenols (compounds with antioxidant properties), which exist in tea leaves, may bind inorganic iron mineral before it is excreted in the feces. In order to prevent this, one does not need to give up drinking tea, but instead make sure not to drink it while consuming iron-rich plant foods,” he advises.

Will Tea Survive the Climate Crisis?

The climate crisis brings with it many changes and different regions of the world are experiencing major climate fluctuations, ranging from heat and droughts to floods, storms and extreme cold. This could threaten the continued survival of agricultural crops. Some plants have crossed oceans and been absorbed by other continents, but what about those that require special conditions to thrive? Will the tea plant survive the changing conditions?

“A plant can adapt to new conditions up to a certain limit,” says Prof. Shaul Yalovsky of the School of Plant Sciences and Food Security at The George S. Wise Faculty of Life Sciences, who studies plant development mechanisms and their response to environmental stresses. His lab has succeeded in developing tomato varieties that consume less water and still deliver the same amounts of fruit while maintaining its quality.

“Tea is a crop that grows in very rainy areas. Therefore, it is not cultivated in an area like Israel, for example. Tea plantations are usually located on hills, where the weather is humid and cool to the appropriate extent and the soil is deep enough.”

The tea fields stretching over hills and mountains. Tea harvest in action


Disguised as Tea

Did you know that red “tea” (also known as “red bush tea”) is actually an infusion from the Rooibos plant that grows in South Africa? Because it is processed in the same way as the tea plant, it is commonly referred to as “red tea”, while in reality it is not a tea, but an herbal infusion. It is naturally caffeine-free.


Just like many other plants, tea requires specific conditions to grow: deep and airy soil rich in minerals, and an optimal temperature range between 18 and 20 degrees Celsius. “Tea is sensitive to cold, dryness, humidity and lighting conditions. For example, high humidity impairs the quality of the tea while periods of dryness increase its quality, and growing at high altitudes increases the quality of the tea but lowers the amount of crop,” explains Prof. Yalovsky.

The tea is grown in Asia, Africa and South America. The six largest tea producers in the world are China, India, Kenya, Sri Lanka, Vietnam and Turkey. So what happens if growing conditions in East and Southeast Asia change? Prof. Yalovsky explains that it is necessary to adapt the types of tea plants according to their growing areas. “What works at one location does not necessarily work elsewhere: what grows well in East and Southeast Asia will not necessarily grow well in Kenya or Turkey, for example. Even if we should manage to copy a crop from one place to another, we may not succeed in maintaining its qualities and taste.”

When we drink Earl Grey tea we expect a very specific taste, and if the same tree were to be grown elsewhere – where the temperature may be the same as the original habitat but the soil is not – we would likely notice a change in the taste of the product. This is possibly one of the reasons why drinking Japanese green tea differs in taste from Chinese green tea.

With regard to the future of the in-demand beverage, Prof. Yalovsky says: “Even if the regions of the cultivated areas should experience floods – the tea plantations are positioned on the slopes of hills and mountains so it should not become an issue.” Another good news is that unlike many crops that depend on pollination to develop fruit – the tea plant is less reliant on this. “In the production of tea, we use its leaves and not its flowers or fruits and so it can be propagated by pruning (cutting a branch from a mature plant, a so-called ‘mother plant’, and creating a new plant through rooting). This method also ensures the genetic uniformity of the ‘daughter plants’, with everything that implies,” he concludes.

We made sure to ask Guy Shalmon which type of tea (if any) he recommends that our students drink during the exam period, to which he replied: “Actually, I wouldn’t say there’s any unique advantage or need to drink tea during an exam period. I’d say drink the kind of tea that you fancy and, ideally, try to rotate different types of tea. If the need for caffeine is the main consideration, black tea is the best choice, as it has the highest caffeine concentration. Black tea contains approx. 60-40 mg of caffeine per cup, while green tea contains only 20-15 mg.”

Well, who needs the exams as an excuse, anyway? If you’re like us, we suggest you pour yourself a cuppa on any day of the week – no special occasion required – and enjoy a peaceful break from everything and everyone.

The Ultimate Solution to Global Warming?

Breakthrough TAU discovery may accelerate an industrial transition to sustainable energy.

Hydrogen-powered bicycles and cars have been in serial production for years. In these vehicles, the regular polluting lithium battery has been replaced by a fuel cell that converts hydrogen, a non-polluting fuel, to electricity. Most of today’s hydrogen is, however, still produced from natural gas in a highly polluting process and is therefore referred to as gray hydrogen. Not only is natural gas a non-renewable source of energy, but it also creates carbon dioxide gas when burned, damaging our environment and contributing to global warming.

Enter a new TAU discovery, which may boost the industrial transition from using polluting gray hydrogen to environmentally friendly green hydrogen: Researchers identified a mutant of a known strain of microscopic algae that allows, for the first time, the production of green hydrogen gas via photosynthesis on a scale suited to industrial requirements. Hydrogen gas can thus be produced solely through renewable energy and in a climate-neutral manner, reducing our carbon footprint and greenhouse gas emissions dramatically to stabilize global temperatures. 

Humanity’s transition to the use of green hydrogen may be the ultimate solution to the problem of global warming.

The microscopic algae

Continuous Production Achieved

The study was led by doctoral student Tamar Elman, under the supervision of Prof. Iftach Yacoby from the Renewable Energy Laboratory of The George S. Wise Faculty of Life Sciences at Tel Aviv University. The study was recently published in the prestigious journal Cell Reports Physical Science

While production of green hydrogen is possible through solar panels wired to devices that perform water breakdown into hydrogen and oxygen (electrolysers), the researchers explain that this is an expensive process, requiring precious metals and distilled water. In nature, hydrogen is produced as a by-product of photosynthesis for periods of minutes by micro-algae, unicellular algae found in every water reservoir and even in the soil. For this biological process to become a sustainable source of energy, however, humanity must engineer micro-algae strains that produce hydrogen for days and weeks.

Prof. Yacoby explains that as part of the laboratory tests, the researchers identified a new mutant in microscopic algae that prevents oxygen from accumulating at any lighting intensity, and therefore hypothesized that continuous hydrogen production could be achieved from it. With the help of bioreactor measurements in liter volumes, they were indeed able to prove that hydrogen can be produced continuously for more than 12 days.

According to Prof. Yacoby, the new mutant overcomes two major barriers that have so far hindered continuous production of hydrogen:

  1. Accumulation of oxygen in the process of photosynthesis – As a rule, oxygen poisons the enzyme that produces hydrogen in algae, but in the mutation, increased respiration eliminates the oxygen and allows favorable conditions for continuous hydrogen production.
  1. Loss of energy to competing processes – And this includes carbon dioxide fixation into sugar. This, too, has been solved in the mutant and most of the energy is being channeled for continuous hydrogen production.

To industrialize these results, the research team led by Prof. Yacoby is working on a pilot program of larger volumes and the development of methods that will allow the time of hydrogen harvest to be extended, in order to reduce its cost to competitive levels. “The rate of hydrogen production from the new mutant reaches one-tenth of the possible theoretical rate, and with the help of additional research it is possible to improve it even further,” concludes Prof. Yacoby.

 

Tamar Elman and Prof. Iftach Yacoby in the lab

Featured image: Tamar Elman and the microscopic algae

Hitting Rock Bottom?

First meta-analysis of its kind shows warming of Mediterranean Sea causes marine species to migrate.

As has been heavily discussed at the recent the UN Climate Change Conference (COP26) in Glasgow, our entire planet has been warming in recent decades. This process has been particularly marked in the Mediterranean Sea, where the average water temperature rises by one degree every thirty years, and the rate is only accelerating. One of the urgent questions that must be asked is how, if at all, the various species living in the Mediterranean will adapt to this sudden warming.

In recent years, evidence has accumulated that some species have deepened their habitats in order to adapt to global warming, while other studies have found that species are limited in their ability to deepen into cooler water. A new TAU study shows that there are species of marine animals such as fish, crustaceans and mollusks (for example squid) that change their habitats and deepen an average of 55 meters across the climatic gradient of the Mediterranean (spanning a range of 60 C) to live in cooler waters.

The Mediterranean – An Ideal Test Case

“It should be remembered that the Mediterranean was hot in the first place, and now we are reaching the limit of many species’ capacity,” explains Prof. Jonathan Belmaker from the School of Zoology in The George S. Wise Faculty of Life Sciences. “Moreover, the temperature range in the Mediterranean is extreme – cold in the northwest and very hot in the southeast. Both of these factors make the Mediterranean an ideal test case for species’ adaptation to global warming.”

The groundbreaking study was led by PhD student Shahar Chaikin under the supervision of Prof. Jonathan Belmaker, and along with researchers Shahar Dubiner, all from the School of Zoology in The George S. Wise Faculty of Life Sciences and The Steinhardt Museum of Natural History at Tel Aviv University. The results of the study were published in the journal Global Ecology and Biogeography, and have far-reaching implications for both fishing and future marine nature reserves.

Life at the Bottom

Cause for Preparation

The results of the study have many implications for the future, in the Mediterranean and in general, given that the response of each species to rising temperatures can be predicted according to its traits, such as temperature preference. This, for the first time, offers researchers the opportunity to forecast changes in the composition of the marine community, as well as for the public the opportunity to prepare for these changes accordingly.

“Our research clearly shows that species do respond to climate change by changing their depth distribution,” Chaikin concludes, “and when we think about the future, decision-makers will have to prepare in advance for the deepening of species. For example, future marine nature reserves will need to be defined so that they can also provide shelter to species that have migrated to greater depths. And on the other hand, fishing in the future will involve fishing the same fish at greater depths, which means sailing further into the sea and burning more fuel.”

So, How Deep is Our Love?

In the framework of the study, the Tel Aviv University researchers conducted a meta-analysis of data on the depth distribution of 236 marine species collected in previous bottom-trawl surveys. The data collected revealed for the first time that species deepen their minimum depth limits in parallel with warming seawater temperatures, from the west to the east Mediterranean, and on average deepen 55 meters across the Mediterranean (a range of 60 C).

However, the pattern of deepening is not uniform between species: cold-water species were found to deepen significantly more than warm-water species, species that live along a narrow depth range deepen less than species that live along a wide depth gradient, and species that can function within in a wider temperature range deepen more than those who can function only within a narrow temperature range.

“Various studies collect fishing data from trawling – that is, a boat that drags a net along the seabed and collects various species – and these studies often also measure the depth at which the species were caught in the net,” says Shahar Chaikin. “We cross-referenced these data with water temperature data, and by analyzing 236 different species we came to a broad and compelling conclusion: there has been a deepening of the depth limits of species’ habitats. The minimum depths for species in the Mediterranean are getting deeper, while the maximum depths remain stable. The deepening effect was found to be more significant among cold-water species. In contrast, there are species that function within a narrow temperature range and at a certain depth that deepen much less, probably because they cannot survive in deeper water.”

 

“Even if species deepen to escape the warm waters and this rapid adaptation helps them, there is still a limit – and that limit is the seabed,” adds Prof. Belmaker. “We are already seeing deep-sea fish like cod whose numbers are declining, probably because they had nowhere deeper to go.”

Seahorses – Slow, but Fierce

Terrible swimmers with incredible preying capability.

Seahorses are not exactly Olympic swimmers, in fact they’re considered to be particularly poor swimmers. Despite being relatively slow, however, they are adept at preying on small, quick-moving animals. In a new study conducted at Tel Aviv University, researchers have succeeded in characterizing the incredible preying capability of seahorses, discovering that they can move their head up at the incredible speed of 0.002 seconds. The rapid head movement is accompanied by a powerful flow of water that snags their prey right into the seahorse’s mouth. How was this spring mechanism formed? When did it develop? The researchers hope the recent study will lead to further studies designed to help solve the riddle of spring fish.

The study was led by Prof. Roi Holzman and the doctoral student Corrine Jacobs of the School of Zoology at The George S. Wise Faculty of Life Sciences and the Steinhardt Museum of Natural History at Tel Aviv University, and was conducted at the Interuniversity Institute for Marine Sciences in Eilat. The study was published in the Journal of Experimental Biology.

Springing to Action

The researchers explain that seahorses are fish that possess unique properties such as male ‘pregnancy’, square tail vertebrae, and of course the unique eating system. For most of the day, seahorses are anchored with their tail to seaweeds or corals with their head tilted downward, close to their body. However, when they detect prey passing over them, they lift their head at incredible speed and catch it. According to Prof. Holzman, while preying, seahorses turn their body into a kind of spring: using their back muscles, they stretch an elastic tendon, and use their neck bones as a ‘trigger’, just like a crossbow. The result is faster than even the fastest muscle contraction found anywhere in the animal world.

However, until now it was not clear how the spring-loaded mechanism enabled seahorses to actually eat. Just as anyone who tries to remove a fly from a cup of tea knows, water is a viscous medium and the fish needs to open its mouth to create a flow that draws the prey in. But how do seahorses coordinate snagging in prey with their head movement?

In their recent study, researchers from Tel Aviv University succeeded in characterizing and quantifying seahorse movement by photographing their attack at a speed of 4,000 images per second, and using a laser system for imaging water flows. This measurement showed that the ‘crossbow’ system serves two purposes: facilitating head movement and generating high velocity suction currents – 10 times faster than those of similar-sized fish. These advantages enable seahorses to catch particularly elusive prey.

Evolution of the Spring Mechanism

The new measurements also help shed light on the ecology of various species of seahorses, distinguished from each other by the length of their noses. “Our study shows that the speed of head movement and suction currents are determined by the length of a seahorse’s nose”, Prof. Holzman added. “From the evolutionary aspect, seahorses must choose between a short nose for strong suction and moderate head raising, or a long nose for rapid head raising and weaker suction currents. This choice, of course, corresponds to the available diet: long-nosed species catch smaller, quicker animals whereas short-nosed species catch heavier, more ponderous ones.”

 

Prof. Roi Holzman hopes the recent study will lead to further studies to help solve the riddle of spring fish

According to Prof. Holzman, seahorses are not the only instance of the impressive spring mechanism. Actually, seahorses are counted among the family of fish bearing the appropriate scientific name Misfit Fish, including species such as alligator pipefish, shrimpfish, and cornetfish or flutemouths.

“These fish are called that because of their odd shape which enables stretching their body into a spring. The big question applies to the evolution of the spring mechanism, how it was formed and when it developed. I hope our recent study will lead to further studies designed to help solve the riddle of spring fish”. 

Are We Getting to the Root of Cancer?

Groundbreaking discovery that plant roots grow in a spiral motion inspires search for similar motion in cancer cells.

In an interdisciplinary research project carried out at Tel Aviv University, researchers from the School of Plant Sciences affiliated with The George S. Wise Faculty of Life Sciences collaborated with their colleagues from the Sackler Faculty of Medicine in order to study the course of plant root growth. Aided by a computational model constructed by cancer researchers studying cancer cells, adapted for use with plant root cells, they were able to demonstrate, for the first time in the world, and at the resolution of a single cell, that the root grows with a screwing motion – just like a drill penetrating a wall. In the wake of this study, the cancer researchers conjecture that cancer cells, too, are assisted by a spiral motion in order to penetrate healthy tissue in the environment of the tumor, or to create metastases in various organs of the body. The research was led by Prof. Eilon Shani from the School of Plant Sciences and Food Security and Prof. Ilan Tsarfaty from the Department of Clinical Microbiology and Immunology at Tel Aviv University, and was conducted in collaboration with researchers from the USA, Austria and China. The article was published in March 2021 in the acclaimed journal Nature Communications.

Significant Advance in Plant Research – and in the War on Cancer?

The researchers in Prof. Shani’s group, led by Dr. Yangjie Hu, used as a model the plant known as Arabidopsis. They marked the nuclei of the root cells with a fluorescent protein and observed the growing process and movement of the cells at the root tip through a powerful microscope – approximately 1000 cells in each movie. Furthermore, in order to examine what causes and controls the movement, they focused on a known hormone named auxin, which regulates growth in plants. They built a genetic system that enables activation of auxin production (like a switch) in a number of selected cells-types, and then monitored the influence of the on/off mechanism, in four dimensions – the three spatial dimensions and the dimension of time. After each instance of auxin biosynthesis, each of the thousand cells was video recorded for a period of 6 to 24 hours, thus an enormous amount of data accumulated.

WATCH: The process of growth and movement of cells at the root tip using a microscope

For the next stage, the researchers were aided by the computational tools provided by Prof. Tsarfaty, which had been developed in his laboratory for the purpose of monitoring the development of cancerous growths. They used these tools to analyze the imaging data obtained in the study. Thus they were actually able, for the first time, to observe with their own eyes the corkscrew movement of the root, as well as to precisely quantify and chart some 30 root growth parameters relating to time and space – including acceleration, length, changes in cell structure, coordination between cells during the growth process and velocity – for each one of the thousand cells at the root tip. Using fluorescent reporters, the findings even allowed them to precisely assess the movement and the influence of the auxin on the root, and the way in which it controls the growth process. Prof. Shani: “The computational tools that were developed for cancer research have enabled us, for the first time, to precisely measure and quantify the kinetics of growth and to reveal the mechanisms that control it at the resolution of a single cell. By this they have significantly advanced plant research, an area of utmost importance for society – both from an environmental point of view and in terms of agriculture and feeding the population.” Prof. Tsarfaty adds: “This was a synergetic collaboration that benefited and enlightened both parties. In plants, processes take place much more rapidly, and therefore constitute an excellent model for us. In consequence of the findings provided by this plant study, we are presently examining the possibility of a similar screw-like motion in cancer cells and in metastases, in the course of their penetration into adjacent healthy tissues.”

Tel Aviv’s Ecological Oasis: The Yehuda Naftali Botanic Garden at TAU

A donor-supported renovation focuses on research, facilities and visitor access.

By Lindsey Zemler

TAU’s Yehuda  ​Naftali Botanic Garden is a Tel Aviv oasis for all, a collaborative research hub for plant scientists, engineers and neuroscientists, as well as a beautiful urban nature site that welcomes schoolchildren, soldiers and the general public and numbers among the city’s top tourist attractions.

In the last few months, the Garden has been undergoing a massive rejuvenation and enhancement program.

“Thanks to the generous support of Mr. Yehuda Naftali, this long-awaited renovation marks a significant step forward in our mission to be at the cutting edge of botanical research, education and conservation in Israel,” says Prof. Abdussalam Azem, Dean of the George S. Wise Faculty of Life Sciences, to which the Garden belongs. “This project brings us to the next level in improving infrastructure and access.”

Path construction in progress. Photo: Rafael Ben-Menashe.

A priority in planning the renovations, which are almost complete, was to increase access to all corners of the 34-dunam (8-acre) site, including to school groups, families, researchers, and students. This involved making the paths easier to navigate with wheelchairs, strollers, or groups.

Upon entering, the visitor will enjoy seeing native flora in the new beds adjacent to the garden’s western boundary fence, which are placed according to where they are found in Israel, from north to south.  The acacia tree planted by Mr. Naftali at the Garden’s inauguration in 2019 can be found there, growing nicely.

A variety of paths throughout the Garden. (Left): A natural blanket of pine needles is reminiscent of a walk through the Carmel Forest. Photos: Rafael Ben-Menashe.

The main pathways are wide, paved and comfortable for walking in groups. Smaller paths branch out among various habitats to allow visitors an immersive nature experience. They are all designed to emulate natural processes; sometimes a section is left unpaved for water flow.

Water pond with newly added wooden deck. Photo: Moshe Bedarshi.

Rainfall naturally flows downhill and arches in a waterfall to fill a pond, where the addition of wooden decks allows the visitor to stand comfortably at the edge of the water to view wetland plant species.

“When we planned the renovations, we put a lot of thought into the best visitor experience: to create a feeling of being transported to a nature reserve and being able to experience it from close range,” explained Kineret Manevich, Public Outreach Coordinator of the Garden.

New irrigation control center (left) and irrigation pipe (right) in the pine forest habitat. Photos (left) by Rafael Ben-Menashe and (right) by Moshe Bedarshi.

A new computer-controlled irrigation system is part of the critical infrastructure changes in the renovation plan. A large, complex network of pipes provides thousands of plants with essential water.

(Left): Rare plants being cared for in the nursery and (right) image of geo-mapping software. Photo (left) by Rafael Ben-Menashe and (right) courtesy of the Botanic Garden.

The Garden is also an active research center, where every plant is mapped and monitored, creating a robust database of botanical research. In addition, rare plants are rehabilitated and returned to nature.

The Garden offers a complete sensory experience, full of texture, color and shapes.

The area is a living ecosystem providing refuge to plants, animals, and of course, humans seeking nature without leaving Tel Aviv. The Yehuda Naftali Botanic Garden will be open to the public, and together with the adjacent Steinhardt Museum of Natural History will welcome visitors of all kinds.

TAU researchers discover unique, non-oxygen breathing animal

The tiny relative of the jellyfish is parasitic and dwells in salmon tissue.

Researchers at Tel Aviv University have discovered a non-oxygen breathing animal. The unexpected finding changes one of science’s core assumptions about the animal world.A study on the finding was published on February 25 in PNAS by TAU researchers led by Prof. Dorothee Huchon of the School of Zoology at TAU’s George S. Wise Faculty of Life Sciences and Steinhardt Museum of Natural History.The tiny, less than 10-celled parasite Henneguya salminicola lives in salmon muscle. As it evolved, the animal, which is a myxozoan relative of jellyfish and corals, gave up breathing and consuming oxygen to produce energy.

Living without oxygen

“Aerobic respiration was thought to be ubiquitous in animals, but now we confirmed that this is not the case,” Prof. Huchon explains. “Our discovery shows that evolution can go in strange directions. Aerobic respiration is a major source of energy, and yet we found an animal that gave up this critical pathway.”Some other organisms like fungi, amoebas or ciliate lineages in anaerobic environments have lost the ability to breathe over time. The new study demonstrates that the same can happen to an animal — possibly because the parasite happens to live in an anaerobic environment.Its genome was sequenced, along with those of other myxozoan fish parasites, as part of research supported by the U.S.-Israel Binational Science Foundation and conducted with Prof. Paulyn Cartwright of the University of Kansas, and Prof. Jerri Bartholomew and Dr. Stephen Atkinson of Oregon State University.

Reversing what we know about evolution

The parasite’s anaerobic nature was an accidental discovery. While assembling the Henneguya genome, Prof. Huchon found that it did not include a mitochondrial genome. The mitochondria is the powerhouse of the cell where oxygen is captured to make energy, so its absence indicated that the animal was not breathing oxygen.Until the new discovery, there was debate regarding the possibility that organisms belonging to the animal kingdom could survive in anaerobic environments. The assumption that all animals are breathing oxygen was based, among other things, on the fact that animals are multicellular, highly developed organisms, which first appeared on Earth when oxygen levels rose. “It’s not yet clear to us how the parasite generates energy,” Prof. Huchon says. “It may be drawing it from the surrounding fish cells, or it may have a different type of respiration such as oxygen-free breathing, which typically characterizes anaerobic non-animal organisms.” According to Prof. Huchon, the discovery bears enormous significance for evolutionary research.“It is generally thought that during evolution, organisms become more and more complex, and that simple single-celled or few-celled organisms are the ancestors of complex organisms,” she concludes. “But here, right before us, is an animal whose evolutionary process is the opposite. Living in an oxygen-free environment, it has shed unnecessary genes responsible for aerobic respiration and become an even simpler organism.”
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