Domain movement within a gene: a novel evolutionary mechanism for protein diversification.

ABSTRACT: A protein function is carried out by a specific domain localized at a specific position. In the present study, we report that, within a gene, a specific amino acid sequence can move between a certain position and another position. This was discovered when the sequences of restriction-modification systems within the bacterial species Helicobacter pylori were compared. In the specificity subunit of Type I restriction-modification systems, DNA sequence recognition is mediated by target recognition domain 1 (TRD1) and TRD2. To our surprise, several sequences are shared by TRD1 and TRD2 of genes (alleles) at the same locus (chromosomal location); these domains appear to have moved between the two positions. The gene/protein organization can be represented as x-(TRD1)-y-x-(TRD2)-y, where x and y

SUBMITTER: Furuta Y 

PROVIDER: S-EPMC3077401 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature