Question

I'd like to find out your thoughts about protein structure as it relates to membranes. Specifically, what functions do transmembrane proteins serve? Are there any molecules that could also perform these proteins' functions? Please explain your answer.

Answer 1

Membrane proteins refers to the proteins found in the biological membrane. They are involved in biological processes such as cell-signalling-transduction signal.These membranes play a strong role in controlling a wide array of gradients such as chemical, electrical, and mechanical gradients and are also responsible for the cell structure during key cell events such as division.

FUNCTIONS OF TRANSMEMBRANE PROTEINS

Control of traffic: cells needs to be selectively let in/out a variety of different molecules, from tiny protons to entire protein complexes.

Bioenergetics: as the membrane is able to hold an ion gradient (i.e. keep more of an ion on one side than the the other), MPs can utilize these gradients to create useful energy for the cell

Signal transduction: MPs act as receptors for external stimuli which allows the cell to communicate with the outside world - these proteins are known as cell surface receptors.

Enzymatic action: of course, if a reaction needs to happen at the membrane, the enzyme will likely by an MP

Cell adhesion: both for single-cell organisms (Bacterial adhesin) and in cells within multi-celled organisms (Cell adhesion molecule).

Structure: by contributing to membrane fluidity/rigidity and also by connecting cytoskeletal proteins to the membrane

Immunology and pathogenicity: as MPs are the face that a cell shows to the outside world, they are often very important for providing cells with immunological defense (e.g. CD4), but also are a primary route for pathogenic attack.