Evolution of the mouse polyubiquitin-C gene

• Published in: Journal of molecular evolution Vol. 55; no. 2; pp. 202 - 210
• Main Authors: Perelygin, Andrey A, Kondrashov, Fyodor A, Rogozin, Igor B, Brinton, Margo A
• Format: Journal Article
• Language: English
• Published: Germany Springer Nature B.V 01.08.2002
• Subjects: Animals; Base Sequence; Cricetinae; Crossing Over, Genetic; DNA; Evolution, Molecular; Evolutionary biology; Gene Expression Regulation; Homogenization; Humans; Mice; Molecular Sequence Data; Phylogeny; Polymorphism, Genetic; Population genetics; Rats; Recombination, Genetic; Rodents; Sequence Alignment; Sequence Analysis, DNA; Ubiquitin C - genetics
• ISSN: 0022-2844; 1432-1432
• DOI: 10.1007/s00239-002-2318-0

The polymeric ubiquitin (poly-u) genes are composed of tandem 228-bp repeats with no spacer sequences between individual monomer units. Ubiquitin is one of the most conserved proteins known to date, and the individual units within a number of poly-u genes are significantly more similar to each other than would be expected if each unit evolved independently. It has been proposed that the rather striking similarity among poly-u monomers in some lineages is caused by a series of homogenization events. Here we report the sequences of the polyubiquitin-C (Ubc) genes in two mouse strains. Analysis of these sequences, as well as those of the previously reported Chinese hamster and rat poly-u genes, supports the assertion that the homogenization of the ubiquitin-C gene in rodents is due to unequal crossing-over events. The sequence divergence of noncoding DNA was used to estimate the frequency of unequal crossing-over events (6.3 x 10(-5) events per generation) in the Ubc gene, as well as to provide evidence of apparent selection in the poly-u gene.