Tuesday 14 October 2003
Disease-causing missense (and other in-frame) mutations can exert their deleterious effects at the cellular level through multiple mechanisms.
The deleterious effects of missense mutations are commonly attributed to their impact on primary amino acid sequence and protein structure.
Exonic splicing enhancers
Some missense mutations are deleterious because they disturb cis-acting splicing elements-so-called "exonic splicing enhancers" (ESEs).
A pathogenic mechanism involves the addition of a novel N-linked glycan. Up to 1.4% of known disease-causing missense mutations are predicted to give rise to gains-of-glycosylation.
For some of these mutations, the novel glycans have been shown to be both necessary and sufficient to account for the deleterious impact of the mutation.
The chemical complementation of cells from patients in vitro with various modifiers of glycosylation has been demonstrated and raises the possibility of specific chemical treatments for patients bearing gain-of-glycosylation mutations.
Vogt G, Vogt B, Chuzhanova N, Julenius K, Cooper DN, Casanova JL. Gain-of-glycosylation mutations. Curr Opin Genet Dev. 2007 Jun;17(3):245-251. PMID: #17467977#
DePristo MA, Weinreich DM, Hartl DL. Missense meanderings in sequence space: a biophysical view of protein evolution. Nat Rev Genet. 2005 Sep;6(9):678-87. PMID: #16074985#