HIV particles budding from the surface of a T cell

Researching membrane proteins

Why do researchers study membrane proteins?

Around one-third of all proteins are linked to membranes in some way. The ones that sit within the membrane (integral membrane proteins) are hard to study because pulling them out of their fatty surrounding often wrecks their normal structure. But examining these proteins’ structure and function shows how their roles in signalling can be exploited, either by viruses trying to bypass cell defences or by researchers developing drugs to treat disease.

One important focus for studies of membrane proteins is the action of HIV, which causes AIDS. The virus particle enters one kind of cell (a helper T cell) in the immune system by first binding to a cell surface receptor protein called CD4. HIV has an outer envelope that can fuse with the host cell membrane, allowing viral genes and proteins to enter the cell. Several other cell-surface receptors, and other chemical messengers, can help or hinder the fusion of membranes. Work on understanding exactly how they interact with each other suggests new targets for anti-HIV drugs.

Lead image:

HIV particles budding from the surface of a T cell.

R Dourmashkin/Wellcome Images CC BY NC

About this resource

This resource was first published in ‘The Cell’ in February 2011 and reviewed and updated in September 2015.

Topics:
Cell biology, Medicine, Health, infection and disease
Issue:
The Cell
Education levels:
16–19, Continuing professional development