ProtLlifePred - protein N-end rule prediction server
Welcome in ProtLifePred server. Use it to predict how stable your protein is in the cell. The protein half-life is only rought estimation and is not applicable for N-terminally modified proteins. It is based on the N-end rule. Other additional factors can also affect overall stability of protein. In a nutshell, protein degradation is strictly connected with ubiquitylation pathway.

Define organism:
S. cerevisiae   E. coli   mammalian

Paste plain amino acid sequence in one letter code



N-end rule is based on onbservations from early 80's (done mainly by Vershavsky). It emerges that the most important deteriminant of protein stability is its N-terminal amino acid. depending on organism additional features also can be importans. For example, in eucaryotes there are three important factors which should be taken into account: N-terminal residue, first lysine (used by ubiquitylation machinery) and flexible, disordered regions in thei proximity.

Additionally, for yeast it is possible to determine protein half-life more precisiouly thanks to whole genome study of Belle and coworkers.

protein half-life N-end rule degradation proteosome
Schematic representation of N-end rule pathway in yeast. Degradation of proteins in proteosome depends on aminoacid type on the N-terminus of protein. Some proteins requires modification(s) before they can be processed directly by UBR1 (primary N-recognin). This includes deamidation (NTA1) and attachment of additional arginine (ATE1).

Service results are based on: 

Bachmair A, Finley D, Varshavsky A. In vivo half-life of a protein is a function of its amino-terminal residue. Science. 1986 Oct 10;234(4773):179-86.
Varshavsky A. The N-end rule pathway of protein degradation. Genes Cells. 1997 Jan;2(1):13-28.
Varshavsky A. The N-end rule: functions, mysteries, uses. Proc Natl Acad Sci U S A. 1996 Oct 29;93(22):12142-9.
Belle A, Tanay A, Bitincka L, Shamir R, O'Shea EK. Quantification of protein half-lives in the budding yeast proteome. Proc Natl Acad Sci U S A. 2006 Aug 29;103(35):13004-9.

Suggestions, comments: protein.n.end.rule[at}gmail.com

Copyright 2010 BioPred All Rights Reserved