Which way is up?
Kat - This month I'm reporting back from the Genetics Society Autumn Meeting, which took place at the Royal Society in London. Called "Genes to Shape", the talks brought together researchers ranging from mathematicians and physicists to developmental biologists to discuss how biological shapes are created.
Dr Veronica Grieneisen from the John Innes Centre in Norwich, is figuring out how cells know which way is up, and start to organise themselves into tissues.
Veronica - For a scientist, I think we look at nature and we have many questions. But what's really close to my heart is to try to understand how cells can understand position within themselves but also amongst themselves. And so, that's not only in plant cells, but also in animal cells which are moving around.
Kat - I guess how do we know where we are and what we're doing?
Veronica - Exactly and not only where we are and what we're doing, but what is our head and what is our tail. And so, for us, we already come with our head and with our feet, but for plants say, or for cells, they actually have to establish that information. I mean, if you think about a cell, you have a bag of proteins in the nucleus, but who's telling that cell what part of that membrane will be at the front and what part of that membrane will be at the back? And so, that is something that we're investigating and we see that this information is coming from within and it can be spontaneously generated.
Kat - I really loved it in your talk when you showed a blob which is a cell that had had its nucleus, its DNA, taken away and you kind of poke it, and it moves by itself. What's going on there?
Veronica - So, those are really classical experiments and it's quite mind boggling because then the cell without a nucleus, it's able to detect a gradient. It's able to do really complex things. What we realise there is that it's all through the dynamics of these proteins within. And so, that's what we're able to explain, only through modelling. So, we're bringing in mathematical formulations of what's happening and what's most interesting for us is now, we're discovering that exactly the same process is happening in plants while these two, animals and plants, they have diverged 1.6 billion years ago. So, this logic of how a cell polarises is really, really ancient.
Kat - And it's the same proteins - you have proteins at the front of the cells, proteins at the back, and they're the same proteins doing this.
Veronica - Basically, they're very similar. So, these are the small G proteins, but what is the same is the mechanism. So, maybe the proteins are a little bit different but the way they do it is the same. We think that afterwards, when multi-cellularity has been evolved, although it's been done independently in plants and animals, you're still stuck with the same principles.
Kat - And so ultimately, where do you hope that your work is going to take you because at the moment, you're just kind of modelling single cells. Where do you want to go with it?
Veronica - So, indeed. We're understanding the single cell, but what we're doing now is we're putting them together. So first, how does one cell speak to its neighbouring cell? So, how do you get interesting conversation between two cells? For example in plants, we know that we have these jigsaw puzzle-like shaped cells and they have to coordinate their jigsaw shape with their neighbouring cells. What we saw is that the way that they communicate can also be extended over many, many cells. So then, suddenly we can understand how our organs can give information from one region to the other. So basically, it's everything about scaling. We understand first the individual cell then its interactions, and then suddenly, we can understand more of this emerging behaviour on the level of many, many cells.
Kat - That was Veronica Grieneisen from the John Innes Centre in Norwich.