Biology:Palmitoyl acyltransferase

Palmitoyl acyltransferase is a group of enzymes that transfer palmityl group to -SH group on cysteine on a protein. This modification increases the hydrophobicity of the protein, thereby increasing the association to plasma membrane or other intramembraneous compartments.

Domain structure

The palmitoyl acyltransferase was isolated and identified in 1999. The catalytic domain of the protein has aspartate-histidine-histidine-cysteine (DHHC) in the core and therefore is called DHHC domain.

Substrate proteins

The example of substrate includes H-Ras, N-ras, R-Ras, RhoB, Cdc42 inform 2, Rab10, Galpha subunit of trimeric GTP binding proteins, Src family tyrosine kinases, GAP53, eNOS, AMPA receptor subunit GluR1 and GluR2, GABA_A receptor gamma2 subunit, aquaporin, KV1.1, rhodopsin, beta2-adrenergic receptor, and PSD-95. https://swisspalm.org/enzymes

Physiological Functions

The protein palmitoylation is a reversible process. The addition of palmitoyl group increase the membrane association of the substrate protein while the removal by palmitoyl thioesterase decreases the membrane association.

References

• Draper, J. M.; Smith, C. D. (2009). "Palmitoyl acyltransferase assays and inhibitors (Review)". Molecular Membrane Biology 26 (1): 5–13. doi:10.1080/09687680802683839. PMID 19152182. 
• Creaser, S. P.; Peterson, B. R. (2002). "Sensitive and rapid analysis of protein palmitoylation with a synthetic cell-permeable mimic of SRC oncoproteins". Journal of the American Chemical Society 124 (11): 2444–2445. doi:10.1021/ja017671x. PMID 11890786.