You work with what ?!

A lot of people who I meet will ask me what it is I do. I will normally start with I'm doing my Ph.D and then they'll be in what - and I'll say molecular biology or cell biology. Then they'll be "WOW ! That sounds tough" or "That's great !" or " My god ! I don't have the patience for that ! You must have a special kind of calm." :)

After that the conversation is normally done (80% of the time..), but a few times I'll be asked "Oh. What exactly do you study?" and I'll be "Aging and I have particular interest in muscle aging." That 99% of the time is the end of that discussion. Very rarely I'll be asked "So how do you particularly study this...?" and then I'll start a whole series of "Ewwwwwww" or "Yuck..." or "REALLY?!" by saying that I work with worms.

My work revolves around determining what, if any, is the role of small RNA molecules called microRNAs in aging, especially muscle aging (Not going to talk about microRNAs!!). Since these are molecules, I should say at the outset that I am in general a molecular biologist and more specifically a molecular geneticist - since these tiny RNAs have their own genes.

So coming back to worms….Now please don't confuse what worm I'm talking about.

These are NOT the worms I work with - but this is the sort of image that most people hold in their minds. And earthworms are very useful as everyone knows and are actually studied. But they are not model organisms - they are not used to generalize a phenomenon or extrapolate a phenomenon studied in their species to our species, at least, not that I know of.

A model organism is one in which a basic or specific biological phenomenon can be studied in detail and extrapolated to having the overall same mechanism in rats, monkeys, dogs, horses, armadillos, and of course the only real organism we care about, humans. A model organism is usually a simple, well-defined system of whose basic biology is easy to understand and shares (we hope) at least some conserved features across different species of animals (and plants and microbes). They should be easy to maintain and rear, they should not have very long generation times (ideally) and finally if possible, their genetics should be well understood (for my field).

The model organism that I study, the worm Caenorhabditis elegans, is almost microscopic (the adults are normally 1mm and even the mutant long worms are no larger than 2mm). It is completely transparent and is composed of exactly 959 cells (yes! Someone did actually sit and count every single cell and every single descendent of every single cell from the one celled stage). It lives for ~3 weeks in the lab (and it is my duty to make them, and by extension us, live longer and happier) and is super cool J

Here is a video of it moving around on the plate-

C. elegans has been used to figure out the details of several very important biological phenomena including apoptosis (how some of our cells are programmed / induced to die in response to starvation, damage, infection or just while they are forming the organism e.g. our fingers are webbed while we grow - cells in between are programmed to die so we have separate distinct fingers), RNA interference and microRNAs (this is what I study and received last years Nobel Prize in medicine), the signaling that goes on between cells when we’re embryos and a whole lot of other stuff. It’s also been a model for muscle aging since the muscles it uses for movement age and deteriorate almost identically to our own.

In any case - I’m writing this so people have an idea about what model organisms are and why worms and the other model organisms shown below are useful - after all it would be slightly problematic to create mutants of humans by forcefeeding DNA damaging chemicals and exposing your “privates” to radiation to better science and understanding !

Model organisms:

1. Escherichia coli - bacteria, most commonly found in our feces :)

2. Saccharomyces cerevisiae - Bakers yeast found in your nearest bakery - used to study cellular replication

3. Drosophila melanogaster - fruit fly found in rotting fruits, garbage, etc and used as a model to study development of the embryo, Neurological diseases such as Parkinson’s disease, Alzheimer’s disease, heart development, as well as behavioural defects.

4. Mouse - found in the streets of Bombay and formerly in my EX-apartment , used as a model for studying many many many human genetic diseases, obesity, alcoholism, development, etc etc.