Evolutionary divergence of vertebrate Hoxb2 expression patterns and transcriptional regulatory loci

摘要: Hox gene expression is regulated by a complex array of cis-acting elements that control spatial and temporal in developing embryos. Here, we report the isolation striped bass Hoxb2a gene, comparison its to orthologous from zebrafish, comparative genomic analysis upstream regulatory region other vertebrates. Comparison patterns zebrafish revealed similar within rhombomeres 3, 4, 5 hindbrain but notable absence neural crest tissues while observed common Comparative Hoxb2a–b3a intergenic those pufferfish, human, mouse demonstrated presence Meis, Hox/Pbx, Krox-20, Box 1 elements, which are necessary for rhombomere expression. Despite their occurrence, location orientation these transcription differed among five species analyzed, such Krox-20 located 3′ Hox/Pbx bass, human they 5′ this r4 enhancer mouse. Our results suggest plasticity exhibited organization key responsible rhombomere-specific may reflect effects stabilizing selection evolution elements. J. Exp. Zool. (Mol. Dev. Evol.) 294:285–299, 2002. © 2002 Wiley-Liss, Inc.