Is Astrology (Indian) Unscientific Venki?

Yearly visit of Venki Ramakrishnan, the Nobel laureate during the music season in Chennai is studded with a few invited lectures in South India. This time around he gave one memorial lecture in Bharatiya Vidya Bhavan, on the topic 'Skeptical Scientist', which invited first page consideration by the newspapers along with the much discussed Lokpal bill in Indian parliament.

Venki was of the skepticism that astrology along with homeopathy are belief based and could just be fake (according to the news reports). Being an Indian who always has wondered and contemplated about Indian astrology which predicts (precisely!) about different eclipses every year, along with planetary position, I was not able to completely appreciate Venki's opinion, though I too have some reservations about certain aspects of Indian astrology that is purely based on superstition. I don't agree with his analogy of Vitamin C of Linus Pauling. There is definitely a scientific possibility of Vitamin C being a potent anti-oxidant, having potential roles in reducing the risk of cancer and other diseases. I feel it is absolutely scientific to speculate and also suggest that something has a potential as it is equally important to prove it. In the case of vitamin C at least there are quite a few studies that have proven its usefulness in treating (if not curing) some health related defects. Based on this, certain suggestions extrapolating its benefits are bound to come.

Also, Indian astrology at least from what I've read and come to know is not just based on beliefs. It is also based on the impeccable wisdom and observational and analytical brains of our ancestors, who may not have actually recorded their observations as meticulously a modern day scientist does. Our ancestors passed on scientific experience biologically, through sharing their wisdom. Perhaps they thought genetic imprints of knowledge transmitted by 'teaching through practice' would stay immortal as compared to hard prints on a paper. I also feel some of their data which were recorded on non-paper surfaces would have got destroyed or lost. Even today, there are persons in India who calculate (perhaps not using formulas discovered by European or Western mathematicians) planetary positions for the future of earth, its climate, monsoon etc.

I have also had reasonably good experience with homeopathy and other alternative medicines. For example, for cold and allergic esinophilia or even asthma, homeopathy could be a viable alternative to modern medicine where there is no cure. I don't say homeopathy cures asthma. I just say, based on experience of several people, it can alleviate allergic asthma and cold. Of course, nobody has recorded or defined what exactly alleviates asthma in homeopathic formulations, but the truth is it does have positive effects. Sometimes, a purely reductionist approach in science will not work as it worked for ribosome structure and its subsequent utility in antibiotics discovery. The flaw to me only lies with modern science. It doesn't allow and accept people from other medicines to define drug and disease response in a holistic manner. It has gone too deep into the ocean that modern medicine refuses to see the existence of light above the ocean.

I did not have the opportunity to attend Venki's lecture. It is possible that he is misquoted or partially or selectively quoted by the media. But if the media reports are true, I would only argue with Venki regarding his skepticism and also suggest to him, that being a scientist, he should have reviewed literature and data on Indian astrology at least, before being dismissive of astrology as a fake subject. I totally agree with him that astrological predictions should not be based on superstitions.

This is not an emotional reaction by an Indian to Venki's observation; just a counter argument by an 'Argumentative Indian'.

Animation on RNA interference

RNA interference
RNA interference (RNAi) RNA interference (RNAi) is an important pathway that is used in many different organisms to regulate gene expression. This animation introduces the principles of RNAi involving small interfering RNAs (siRNAs) and microRNAs (miRNAs). We take you on an audio-visual journey through the steps of gene expression and show you an up-to-date view of how RNAi can silence specific mRNAs in the cytoplasm.

Is Researchers are a Competent Researcher?

PhD is a unique degree in that it is not focused on acquiring more knowledge.A Masters essentially provides more knowledge or more in-depth knowledge in a subject.But doing a PhD is oriented around research.

Due to the focus and importance of research in PhD,it is often believed that creating new knowledge is the main goal of PhD.Though creating new knowledge is part of the PhD training,the main objective of doing PhD degree is to become a competent researcher who can conduct independent research in his or her chosen area.If we go by the premise that the purpose of a PhD program is to produce competent researchers, then the research done during PhD is primarily for contributing towards this goal and the nature and sophistication of the research output is less important.What is important is to learn to properly formulate a problem and apply suitable techniques to produce results that further the state of understanding about that problem.

The ability to conduct research in an area requires deep knowledge in that area,knowledge about related areas,and the experience of working on research problems,i.e.problems whose outcomes are not known. To develop these critical abilities,PhD candidate have three components in them – some course work to provide the breadth of knowledge,some methods to develop the depth of knowledge in the chosen area of study,and a thesis that provides the experience of working on research problems.Through these components a PhD candidate should able to develop the following abilities,which form the foundation of a career in research:

Ø    Breadth in the discipline --- can be provided through his /her type of work.

Ø    Expertise--- in a vertical area in which the PhD candidate can say “I am an expert in this”i.e.an area in which he has full knowledge of what is known,what is missing,etc.Developing this expertise requires ability to search for relevant work done in an area,as well as the ability to critically read and understand research papers,reports,monographs and appreciate the subtle or complex issues that may be involved.

Ø    Ability to identify research problems--- This is one of the most important abilities for a researcher. This ability requires a good knowledge of the recent developments in the area, and the ability to create a bigger picture and see how the different work fit and what might be missing.Formulating a problem properly is half the research done.In fact,PhD candidates spend much of their time in defining the problem.This skill is strengthened as the person develops the subjective ability of judging results and problems.This skill is also needed by a PhD person as a member of the research community where one is called upon to review other peoples work.

Ø    Ability to actually do the research--- Behind every research there is some new idea, some hypothesis, which forms the foundation of the research work.But doing research is much more than getting an idea.The idea has to be developed using the established paradigms of scientific research, through which the researcher shows the value of the idea.Spending time grappling with research issues, actually doing research,and studying research work of others can help in developing this ability.That is the main reason why doing independent research is always a part of a PhD program.

Ø    Ability to write and present the results--- This is very important and very difficult.Not only are issues of communication involved,but one has to convince a group of peers (who review it and later read it,if published) that the work is worthy of their time,the results have been put in context,the value is clearly articulated,etc.Publishing the results of research has been the time honored tradition and benchmark,and perhaps the only reliable method to subject a research work to scrutiny as well as use by others.

Developing these abilities should be the objective of a PhD program.Note that these abilities do not discuss the actual research results.Those are the outcome of developing these abilities.A PhD degree should result in some research results,which should be peer reviewed and published.Without this,there is no effective method to demonstrate that the ability to do research and communicate the results has been developed. However,in the overall research career,it possesses these abilities that are more important,particularly if one wants to work in industry where the needs may change and problems that a researcher works on may be quite different from the ones chosen in PhD.For a career in academics,however,the actual results are equally important as the evaluative processes often focus on the quality and quantity of research work that has been done during the PhD.

All of these abilities are important to become a competent researcher.As should be clear many of these skills cannot really be taught but are learned largely through commitment,dedication and perseverance.This makes PhD a mostly self driven and self taught degree and also the supervisor gently aiding the process.

Hence,while doing a PhD,the scholar should be self motivated and committed and willing to work hard and long on problems.Research is often a lonely business (except in disciplines where group activity is more common) and PhD is a preparation for a career in it.Research is tough career,but with development of these skills by doing a PhD,it can become easier and more satisfying.

The Origin of Life - Abiogenesis - Dr. Jack Szostak

When I was surfing the internet for reading some information about the origin of life, I came across a video created by Prof. Jack William Szostak, a Noble Laureate in Physiology and Medicine 2009. I thought it will worth all of us to have a look in to that.


It's been 55 years since the Miller-Urey Experiment, and science has made enormous progress on solving the origin of life. This video summarizes one of the best leading models. Yes there are others. Science may never know exactly how life DID start, but we will know many ways how life COULD start. Don't be fooled by creationist arguments as even a minimal understanding of biology and chemistry is enough to realize they have no clue what they are talking about. 


Note on how competition works. Water will flow across a membrane to try to equalize the ion concentration. If there is a lot of polymer in a vesicle it will be surrounded by many ions, thus causing water to flow into the vesicle, increasing the internal pressure and stretching the membrane. Fatty acids are in equilibrium between the vesicle and solution. If 2 vesicles are near one another they will gradually swap fatty acids. If one membrane is under tension, the fatty acid "on rate" will be greater than the "off rate" (move to a lower energy state by relaxing the pressure). It will suck up fatty acids from solution. The other vesicle will still give them off, but they will disappear (sucked up by neighbor) and not return. Therefore, the vesicle with high internal pressure will grow and the neighbor will shrink.

How does A "Good" Protein Hurt Brain Cells after Clot-induced Stroke?

As we all know stroke in human is one of the major problems as it causes sudden death of brain cells. It occurs mainly due to lack of oxygen, when the blood flow to the brain is stopped. There are two main types of strokes; one is ischemic stroke, where blockage of blood flows to a portion of brain occurs by blood clot. The other type is Hemorrhagic stroke, it is caused by the rupture of blood vessel in the brain.

During stroke, the production of thrombin (a "trypsin-like" serine protease protein that has many roles such as blood coagulation, fibrin formation, and platelet activation) is more and plays a negative role as it damages the brain cells. Previously thrombin was found only in Hemorrhagic stroke and now Patrick D. Lyden and his group have found that presence of thrombin Ischemic stroke also.

http://www.medicalnewstoday.com/releases/238238.php

http://www.cdc.gov/stroke/types_of_stroke.htm

LIGER

AMAZING ANIMAL....!! The 10ft Liger who's still growing...

He looks like something from a prehistoric age or a fantastic creation from Hollywood. But Hercules is very much living flesh and blood - as he proves every time he opens his gigantic mouth to roar. Part lion, part tiger, he is not just a big cat but a huge one,standing 10ft tall on his back legs. Called a liger, in reference to his crossbreed parentage, he is the largest of all the cat species.
On a typical day he will devour 20lb of meat, usually beef or chicken, and is capable of eating 100lb at a single setting. At just three years old, Hercules already weighs half a ton.

He is the accidental result of two enormous big cats living close together at the Institute of Greatly Endangered and Rare Species, in Miami, Florida, and already dwarfs both his parents.

"Ligers are not something we planned on having," said institute owner Dr Bhagavan Antle. "We have lions and tigers living together in large enclosures and at first we had no idea how well one of
the lion boys was getting along with a tiger girl, then lo and behold we had a liger."

50mph runner... Not only that, but he likes to swim, a feat unheard of among water-fearing lions. In the wild it is virtually impossible for lions and tigers to mate. Not only are they enemies likely to kill one another, but most lions are in Africa and most tigers in Asia. But incredible though he is, Hercules is not unique. Ligers have been bred in captivity, deliberately and accidentally, since shortly before World War II.

Today there are believed to be a handful of ligers around the world and a similar number of tigons, the product of a tiger father and lion mother. Tigons are smaller than ligers and take on more physical characteristics of the tiger.

Famous cross-breeds

Look at the size of the head on this thing.. :o)

Role of formylated methionine in prokaryotes?

Dear All,
Why in prokaryotes (Bacterias) start codon Methionine is formylated but not in eukaryotes? What will be the significance of formylated methionine in prokaryotes?

Group leaders and Bench work?

While going through the Janelia farm website, one of the principles they uphold caught my eye: They donot burden group leaders with administrative work! Ofcourse they derived a list of such principles from that of  successful labs like the MRC, where even Nobel laureates do active bench work.. It is the same with Department heads, who do experiments with their own hands. This is not the case with most labs here in India. Now, whether it is possible for group heads to take time out from active administrative work and get down to holding pipettes  is a different  story that's not going to be discussed here. It may be inevitable that group leaders do administrative work all the time. But, if they do get to involve themselves in bench work, they by themselves are a motivation to  young recruits in the lab. Another big plus is that many get to do things the right way,and get to build the confidence to try out new experiments just by watching the way their mentors work. Also it keeps a check on the use of chemicals and consumables in the lab:)

Just thought would post this picture whisked from the web. This could be the scenario in most labs, should we think it might not apply to us as most of us don't wear labcoats at all?:)

Novel application of Laser Transmission Spectroscopy technology (LTS) as a DNA diagnostic tool

Hi All,

Here is an interesting new technique called Laser Transmission Spectroscopy (LTS), a quantitative and rapid in vitro technique used to measure the size, shape and number of nano particles in suspension. Physicists Carol Tanner and Steven Ruggiero from the University of Notre Dam have applied LTS as a novel detection method for species-specific DNA detection.

LTS technique has many advantages over other established DNA detection techniques. The technique is highly sensitive and takes only a few seconds to genetically score a sample for species presence or absence. This technique could possibly eliminate the need for pcr amplication of products required to do marker analysis or in forensic studies.

Although the current paper describes the use of LTS in invasive species detection, the Notre Dame researchers believe that the technique could serve as an important tool in detecting human pathogens and understanding and indicating the presence of genetic diseases such as cancer.

Full-length Article can be obatined from
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0029224

Mouthless and gutless animal????????

Paracatenula galateia, belong to the platyhelminths or flatworms, but inside they don't look like your usual fluke or tapeworm. Their bacteria-filled sac, called the trophosome, accounts for over 90% of the worm’s body and has cells called bacteriocytes that are filled with bacteria. In some species, the bacteria make up close to 50% of the total volume of the worm. By the way, the bacteria are quite big—5 to 8 μm in diameter. Incidentally, such large sizes are also seen in some insect bacterial endosymbionts.
For more information: http://www.ncbi.nlm.nih.gov/pubmed/22131640
http://schaechter.asmblog.org/

Hi all,
Sorry for such a late entry here. Just came across this article and thought it will be useful to all. Its on Rules for Searching and Organizing the Scientific Literature. Its available @ the following link
http://precedings.nature.com/documents/3867/version/1/files/npre20093867-1.pdf
Thanks

How far can we see?

Hi All,
I have a question. How far our eyes can see. What will be maximum distance we can see an object with human eye.

Keeping Bacteria at a distance

Dear All,

As we all know that Human Gut (Digestive system) is flooded with trillions of bacteria which helps in digestion and energy production, but most of us (may be I am) do not know how these bacterias prevent themselves from our immune system. Here is an article which discusses about our Gut microflora and how they are maintained in our gut with out any infection to the host system.

http://www.hhmi.org/news/hooper20111013.html

http://www.sciencemag.org/content/334/6053/182.full.pdf

Marker free transgenic crop plants

Dear all,
I just thought about marker free transgenic crop plants when i was cloning a gene (the gene which i work on) in plant expression vector that we recently bought in our lab. The thought was to generate plant with vector merely having desired gene, promoter, terminator and of course, the DNA region required for integration. It should not have any marker genes like hygromycin, kanamycin and even reporter genes such as GUS, GFP. The question came in my mind is that why do we need to use all these genes to screen transgenic plants when we have primers.

Are those marker genes going to enhance transformation frequency?

Is that laborious or not possible to generate transgenic plants with out having selection markers?

I welcome your comments and suggestions.

Chew gum, lose weight

Syracuse University scientist uses vitamin B12 to orally deliver appetite-suppressing hormone” 

Most people understand that serious weight loss requires changing attitudes toward what they eat and how often they exercise. But, what if the process could be aided by simply chewing a stick of gum after meals? That’s the question a team of scientists, led by Syracuse University chemist Robert Doyle, is trying to answer. In a groundbreaking new study, Doyle’s team demonstrated, for the first time, that a critical hormone that helps people feel “full” after eating can be delivered into the bloodstream orally.

Doyle’s study was published online Nov. 4, 2011 in the American Chemical Society’s Journal of Medicinal Chemistry and is forthcoming in print. Doyle is an associate professor in the Department of Chemistry in SU’s College of Arts and Sciences. He collaborated on the study with researchers from Murdoch University in Australia.

The hormone, called human PYY, is part of a chemical system that regulates appetite and energy. When people eat or exercise, PYY is released into the bloodstream. The amount of PYY that is released increases with the number of calories that are consumed. Past studies have shown that people who are obese have lower concentrations of PYY in their bloodstream both when fasting and after eating than their non-obese counterparts. Additionally, intravenous infusion of PYY into a volunteer group of obese and non-obese individuals increased the serum levels of the hormone and lowered the number of calories both groups consumed.

“PYY is an appetite-suppressing hormone,” Doyle says. “But, when taken orally, the hormone is destroyed in the stomach and that which isn’t destroyed has difficulty crossing into the bloodstream through the intestines.”

What’s needed is a way to disguise the PYY so that it can travel through the digestive system relatively unharmed. Several years ago, Doyle developed a way to use vitamin B12 as a vehicle for the oral delivery of the hormone insulin. B12 is able to pass through the digestive system with relative ease and carry with it insulin, or other substances, into the bloodstream.

Similarly, his research team attached the PYY hormone to his patent-pending vitamin B12 system. “Phase one of this study was to show that we could deliver a clinically relevant amount of PYY into the bloodstream,” Doyle says. “We did that, and we are very excited by the results.”

The next step involves finding ways to insert the B12-PYY system into such things as chewing gum or an oral tablet to create a nutritional supplement to assist individuals in losing weight in much the same way as nicotine-laced gum is used to help people stop smoking. “If we are successful, PYY-laced gum would be a natural way to help people lose weight,” he says. “They could eat a balanced meal, then chew a stick of gum. The PYY supplement would begin to kick in about three to four hours later, decreasing their appetite as they approach their next meal.”

______

Is blogging on science useful?

Doing science requires many attributes in addition to curiosity, especially since it has become so inter-disciplinary. Gone are the days when science was restricted to a royal few or gifted individuals who had the knack of putting thoughts into records or print before they experimented. World is a global village now. Science is connected more effectively with scientists all over the world after the invention of WWW and of course, Google!

I was just thinking how blogging could be a useful utility for scientist... I guess I ended up thinking only about useful aspects of blogging that would run into pages! Thoughts travel faster than the speed of light, if only I can measure. But I'm sure my thoughts can reach some scientist at least in seconds if only the scientist at the other end has access to internet. My hypotheses, abstract musings, enthusiastic questions etc can all be read, reviewed, openly criticized and refined only through this wonderful open access but underutilized(by scientists) phenomenon called 'Blogging'.

I don't have to be a Shakespeare and Einstein at the same time to worry about my abstract scientific thoughts into readable English in a blog. In fact, I can convey what I want to convy in a much more casual way and yet get benefited with a thorough scrutiny by those who read it. I see blogging to be the starting point of a budding researcher's venture into writing for peer-reviewed journals. Above all, blogging makes me not worry about impact factors!!

I was forced to blog about my thoughts on blogging and science primarily because I saw only names in contributors' list but the actual contribution is only from a few! So, let us shun fears of presenting good English, Newtonian science and hesitation and start blogging about science in the true sense without any inhibitions, with just curiosity on mind! If some one is going to suggest time as an excuse, please take a 'time loan' from Facebook or Orkut or Twitter or any of those chat mechanisms that distract. Waiting to see you all blogging on science, because blogging is also a way expand one's scientific acumen.

Where is the ultimate origin?

Scientist or spiritualist, one question that could bother both at any point in time of their life is, 'Where does it all start? There has to be something that created the 'original' because of which the electrons that you see as letters in my blog or me that typed these on a keyboard...

There are again two different ways to ask the question: How am I here and why am I here? and what is my physical origin or the ultimate particle that lead me to do the function of typing at present? The first question is not within the scope of this blog. But the second one, possible to answer through some experiments may in fact reveal the existence or non-existence of the 'God Particle'! There is nothing to do with theism to name it 'God particle'. Just that scientists, particularly physicists perhaps thought it fanciful to name it so.

As a biologist I can always say since I believe in Darwinism and theory of evolution that my ancestors could be and perhaps were bacteria (the limit of origin as I imagine in biological time scale). But then does it stop there? Certainly not! I would be too microscopic not in the sense that bacteria can be seen only using the microscopes, but in the sense that earth is just a small microcosm in the whole universe that till recently has been proven not just to be expanding, but in acceleration!


I am at a time point (perhaps millions and millions of light years from the 'God particle') where it is extremely difficult to even imagine about the original particle that started of the creation of universe. But then there is always a way to experimentally explore through something called 'particle accelerators' (like CERN Large Hardon Collider) to try and recreate the creation of the 'God particle' scientifically termed Higgs Boson. There is a very latest news that the search for it could have been narrowed down.


It must be remembered however that these experiments are recreations of a creation and normally take years in spite of technological advancements. Also, the particle may not be detected at all. So, 'God particle' may or may not be a reality at this point in time. But I strongly feel there must have been some particle that brought me to earth after several expansions of the universe and after very recently (in terms of light years at least!) Darwin took notice of the biological expansion of species!

Novel technique reveals both gene number and protein expression simultaneously

Dear all,

As most of us are working on analysing the gene activity and protein expression here is a technique called Fluorescent in situ gene protein assay that allows us to address gene activity and corresponding protein expression in the same cells at the same time. The new assay is described in the August issue of the journal Neuro-Oncology

Novel technique reveals both gene number and protein expression simultaneously

What is the best way to do science in India?!

Well, many of us who are into research (at least in India) are faced with the problem of doing science the best way and meet the needs of our daily existence. There are two kinds of people that do science: one who pursues it purely as a career option and the other, as a passion. I guess, it is the first set of people who have taken science as a career (by fate or choice) are dominant. But can science by its popular perception of being a utterly curiosity driven, near-stoic (by stoic I mean disengaged from the surroundings, both physically as a scientist or mentally in the thought process) exercise that is not money-oriented be treated as a career option? Maybe yes, only if it is for the sake of running the day-today life as many of the present day researchers have to.

Present day science is an enterprise where 'scientists' need to do more of business of science than than Science. Except for a few isolated cases like IISc, NCBS etc in India where else do we find a science problem is addressed as just a, science problem. These thoughts have been going on in my mind for so long and that's why I asked, 'Which one is better, basic or applied science?'. Just today I came across a report in Nature journal about 'Janelia Farm', an experiment in curiosity driven science that started in 2006 in Virginia U.S. I wish our Indian Govt. also sets up 'farms' like this (of course, without any influences that may be needed to get unrestricted funding or other science corruptions!) in the North, South, East and West. Positions in Janelia are not tenure track and group leaders are reviewed every five years, more importantly not based on the number of publications but based on the questions they asked and how good they were in working towards that question.

Research in Janelia is interdisciplinary which I think is wonderful since there is ample scope for learning about 'other' science! Coming back to my question, is this (like Janelia) the best way to do science?. Perhaps! I am biased towards asking basic questions! I don't know would this model be successful (even Janelia scientists say that they need 5-10years to produce evidence for this innovative model) but I'm pretty sure that this model will create opportunities for those who don't see science in a more conventional way and yet enjoy basic necessities of Indian life.

To me, passion for science should always win over science as a money yielding enterprise! I have much more to blog but let me stop and wait for reactions!!

Evidence of cross kingdom Regulation: Plant miRNA can regulate Human Low Density Lipoprotein receptor adaptor protein 1 (LDLRAP1)

For the past two decades, Lin Zhang, Dongxia Hou, Xi Chen and Donghai Li have been working in existence of plant miRNA in human serum, calf serum and other mammals serum. Here is the first report that "plant miRNA can regulates the human LDLRAP1".

http://immunotrends.blogspot.com/2010/05/micrornas-mirna-are-small-noncoding_8794.html

MicroRNAs (miRNAs), a class of 19-24 nucleotide long non-coding RNAs derived from hairpin precursors, mediate the post-transcriptional silencing of an estimated 30% of protein-coding genes in mammals by pairing with complementary sites in the 3′ untranslated regions (UTRs) of target genes. miRNAs have been widely shown to modulate various critical biological processes,
including differentiation, apoptosis, proliferation, the immune response, and the maintenance of cell and tissue identity. We next characterized the possible carrier of circulating miRNAs. Microvesicles (MVs) are small vesicles that are shed from almost all cell types under both normal and pathological conditions [13, 14]. They bear surface receptors/ligands of the original cells and have the
potential to selectively interact with specific target cells and mediate intercellular communication by transporting Plant MIR168a downregulates mammalian LDLRAP1 bioactive lipids, mRNA, or proteins between cells.

Their previous studies have demonstrated that stable microRNAs (miRNAs) in mammalian serum and plasma are actively secreted from tissues and cells and can serve as a novel class of biomarkers for diseases, and act as signaling molecules in intercellular communication. Here, we report the surprising finding that exogenous plant miRNAs are present in the sera and tissues of various animals and that these exogenous plant miRNAs are primarily acquired orally, through food intake. MIR168a is abundant in rice and is one of the most highly enriched exogenous plant miRNAs in the sera of Chinese subjects. Functional studies in vitro and in vivo demonstrated that MIR168a could bind to the human/mouse low-density lipoprotein receptor adapter protein 1 (LDLRAP1) mRNA, inhibit LDLRAP1 expression in liver, and consequently decrease LDL removal from mouse plasma. These findings demonstrate that exogenous plant miRNAs in food can regulate the expression of target genes in mammals.

In this sense, miRNAs may represent a novel class of universal modulators that play an important role in mediating animal-plant interactions at the molecular level. Like vitamins, minerals and other essential nutrients derived from food sources, plant miRNAs may serve as a novel functional component of food and make a critical contribution to maintaining and shaping animal body structure and function. Extending from this concept, the intake of certain plant miRNAs generation after generation through a particular food source may leave an imprint on the genetic map of the human race. In conclusion, the discovery of plant miRNAs and their roles in the biology of mammalian cells and animal organs represents the first evidence of crosskingdom transfer of functionally active miRNAs and opens a new avenue to explore miRNA-mediated animalplant interactions.

Cell Research advance online publication 20 September 2011; doi:10.1038/cr.2011.158

http://www.nature.com/cr/journal/vaop/ncurrent/full/cr2011158a.html