EVOLUTION OF B2 REPEATS : THE MUROID EXPLOSION

摘要: B2 repeats are a group of short interspersed elements (SINEs) specific for rodent genomes. Copy numbers were determined different genera. All the Muroid (rat, mouse, deer hamster, gerbil) genomes analyzed exhibited 80,000–100,000 copies per haploid genome, whereas squirrel genome contains only 2,500 copies, and fewer than 100 (if any) observed Hystricognath rodents (guinea pig nutria). These findings demonstrate that there was an ‘explosion’ amplification within muroid rodents. The similar copy number species could be explained by formation high proportion prior to divergence species. However, 3′-end sequence is unique between murid cricetid suggesting majority amplified after these Also consistent with recent in parallel finding mouse rat distinct subfamilies repeats. pattern contrasts sporadic nature ID repeat same consensus young subfamily corresponds RNA preferentially transcribed embryonic, tumor, normal liver cells. based on both its low from most element insertions members this subfamily.