Cohesin proteins (also known as chromosome glue) play an important role in mitosis. In this video, Dr Julia Horsfield, from the University of Otago, talks about her research into the alternative roles these proteins play in human development.
Mitosis: The type of cell division that makes new body cells.
Chromosome: A structure within the cell nucleus made of a single coiled piece of DNA
Genes: A segment of a DNA molecule within the nucleus of all cells that codes for a particular protein and determines the traits (phenotype) of the individual.
DR JULIA HORSFIELD
There are many different jobs proteins have in the body. Cohesin proteins are something that organise chromosomes during cell division. So when a cell divides, all of the chromosomes in each of your cells have to replicate, so you end up with two copies of every chromosome, and then this kind of a dance takes place in the cell where the chromosomes have to organise themselves up along the middle of the cell and then be pulled apart to opposite ends of the cell so that you get cell division down the middle, and it’s a very complex orchestration.
But how this is helped by these cohesin proteins is that, when chromosomes have divided, they are held together to start with, and this is so that they can line up and be pulled apart properly. So the cohesin proteins make up the glue that hold the replicated chromosomes together.
And this is relatively well understood – it’s been studied for a number of years – but just in the last 4 years, 5 years, it’s been discovered that this chromosome glue actually does other jobs in the cell on the chromosomes, you know, at times when it’s not needed to hold them together.
So the same proteins, after they have done their glue job, they come back later and hop back on the chromosomes again and they do some other jobs, and those jobs involve regulating the expression of genes that may need to be turned on or off at particular times. So now, the whole field has come into existence – looking at alternative roles for chromosome glue in animal development and in human disease – and that is what my lab is doing at Otago now.
The New Zealand Biotechnology Hub