How does a cell express only one gene out of a large gene family?
Researchers at York Biomedical Research Institute, in collaboration with the University of Dundee have determined how a highly selective protein bridge allows cells to express a single gene from a large gene family.
The Faria Lab at the York Biomedical Research Institute along with colleagues at the Wellcome Centre for Anti-Infective Research, at the University of Dundee have been able to demonstrate a mechanism that allows parasites to survive in their human and animal hosts, by expressing unique and switchable surface coats. This antigenic variation enables them to escape host immune defences.
Several cellular functions depend upon expression of a single uniform type of surface protein or receptor, not just parasitic trypanosomes, the subject of the current study, but also parasites that cause malaria, and the sensory neurons that sense odours in mammals.
The current study builds on previous work and reveals a novel gene expression control mechanism, involving highly selective bridging between two chromosomes. The tethered chromosomes locally assemble an expression factory that maximises the output from a single Variant surface glycoprotein (VSG) gene.
Joana Faria, the first and co-senior author on the paper from the Department of Biology and York Biomedical Research Institute, said:
‘VSG single gene choice is a fine example of ‘extreme biology’, whereby such high levels of VSG expression render trypanosomes a highly amenable system to study fundamental mechanisms by which cells selectively activate genes and enhance their expression’.
Notes to editors:
This work was supported by The Wellcome Trust, and is the result of a collaboration with several colleagues and was greatly facilitated by support from, and access to, the York Bioscience Technology Facility.
The paper can be found here in Nature Communications. You can also read the ‘Behind the Paper’ Nature Communications blog post.