Andre Brown, a researcher at the MRC Laboratory of Molecular Biology, needs your help with watching thousands of hours of videos of nematode worms. Here he tells you what his research into the genetics of the worm’s nervous system will gain from you turning citizen scientist and getting involved in Worm Watch Lab.
I remember when it first struck me. It was a normal day a couple of years ago and I was going about my business in the lab. I’d just finished recording some videos of crawling nematode worms and was looking forward to seeing what I’d captured.
But I ran into a problem: we’d already recorded so many videos that my portable hard drive was full, so I couldn’t transfer the day’s batch to my laptop for viewing. We were recording videos from eight microscopes at the same time so they were adding up quickly. That was when I knew we needed help.
Why do we record videos of crawling worms? The story goes back many years to the work that researcher and Nobel Laureate Sydney Brenner began at the MRC Laboratory of Molecular Biology. In 1963 Brenner wrote a provocative letter to the LMB’s then Director, Max Perutz, saying that it was “widely realised that nearly all the ‘classical’ problems of molecular biology have either been solved or will be solved in the next decade”.
By that he meant that researchers had all-but solved the central concept of molecular biology — how the genetic code is read to make proteins via RNA — and that the institute should also consider how molecular biology is connected to physiology, including how genes affect nervous systems.
Brenner thought the best way to make progress would be to study an animal that has a very simple body. He chose the nematode worm Caenorhabditis elegans, which has a ‘brain’ of only 302 nerve cells (we have billions). Although its body is much simpler than ours, worms still share many genes with humans, and so by studying how genes work in worms we often learn something about how they work in us.
One way to find out what a gene does is to delete it and see what the consequence is for an organism. The problem is that sometimes deleting a gene has no obvious effect on an animal. But we still want to understand what it does, and so we need better ways of finding more subtle changes.
To solve this, I analyse videos of worms to identify the small effects that losing a gene has on behaviour. For some things, such as how fast worms move, we can use computers to find this automatically, but for other behaviours, humans are still much better.
Egg-laying is an example of a subtle behaviour that computers struggle to identify. In the video below, the worm lays two eggs at the same time a bit more than half-way through. Once you’ve seen a couple of eggs being laid, you’ll have no problem finding more examples and that’s why we do it by hand, watching a video and recording the number of times that the worm lays an egg.
This isn’t a problem when you have only a few hours of video, but we’ve collected more than 2,500 hours (more than 100 days of straight movie watching!) and we’re collecting more all the time.
That’s why we teamed up with Zooniverse to get your help. We’ve cut our videos into 30 second chunks and put them on a website where you can watch them and let us know when you see a worm lay an egg. If enough people take part, we should be able to go through all our data in a reasonable amount of time.
We know a lot about how the worm’s nervous system controls egg-laying so if we discover new genes that are involved, we have a pretty good chance of being able to figure out what they do. That’s exciting because some of the genes that affect egg-laying are known to play important roles in humans. A famous example is the neurotransmitter serotonin, which affects mood in humans. Antidepressants like Prozac increase levels of serotonin outside cells in humans. In worms, they stimulate egg-laying.
To help us find functions for more genes in our wormy cousins, go to Worm Watch Lab and get egg hunting!