{PDOC00703} {PS51147; PFTA} {BEGIN} *********************************************************** * Protein prenyltransferases alpha subunit repeat profile * *********************************************************** Protein prenyltransferases catalyze the transfer of an isoprenyl moiety to a cysteine at or near the C-terminus of several eukaryotic proteins. They are heterodimeric enzymes consisting of alpha and beta subunits. The alpha subunit is thought to participate in a stable complex with the isoprenyl substrate; the beta subunit binds the peptide substrate. There are three types of protein prenyltransferases. The alpha subunits of two types, i.e. farnesyltransferase and geranylgeranyltransferase I are encoded by the same gene, FNTA. These proteins bind the same motif (the CaaX box) around the cysteine in their substrates. The third type, geranylgeranyl transferase type II (Rab GG transferase) recognizes a different, non-CaaX motif [1]. Both the alpha and beta subunit show repetitive sequence motifs [2]. These repeats have distinct structural and functional implications and are unrelated to each other. The conserved domain of the alpha subunit consists of about 35 amino acids and is repeated five times. The domain folds into a pair of antiparallel alpha helices, which are packed in a parallel arrangement with adjacent domains in a superhelical pattern (see ). A conserved tryptophan in the fourth position of the second helix interacts with both the first helix and the neighboring helix of the next repeat [3]. Two types of protein prenyltransferase alpha subunits are known: - Farnesyltransferase/geranylgeranyltransferase type-1 subunit alpha (EC 2.5.1.58) (EC 2.5.1.59). - Geranylgeranyl transferase type-2 subunit alpha (EC 2.5.1.60). The profile we developed covers the entire protein prenyltransferases alpha subunit repeat. -Sequences known to belong to this class detected by the profile: ALL. -Other sequence(s) detected in Swiss-Prot: NONE. -Last update: October 2005 / Pattern removed, profile added and text revised. [ 1] Maurer-Stroh S., Washietl S., Eisenhaber F. "Protein prenyltransferases." Genome Biol. 4:212-212(2003). PubMed=12702202 [ 2] Boguski M.S., Murray A.W., Powers S. "Novel repetitive sequence motifs in the alpha and beta subunits of prenyl-protein transferases and homology of the alpha subunit to the MAD2 gene product of yeast." New Biol. 4:408-411(1992). PubMed=1622936 [ 3] Zhang H., Grishin N.V. "The alpha-subunit of protein prenyltransferases is a member of the tetratricopeptide repeat family." Protein Sci. 8:1658-1667(1999). PubMed=10452610 -------------------------------------------------------------------------------- PROSITE is copyrighted by the SIB Swiss Institute of Bioinformatics and distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives (CC BY-NC-ND 4.0) License, see https://prosite.expasy.org/prosite_license.html -------------------------------------------------------------------------------- {END}