期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1993
卷号：90
期号：13
页码：6300-6304
DOI：10.1073/pnas.90.13.6300
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Homeobox genes encode DNA-binding transcription regulators that participate in the formation of embryonic pattern or contribute to cell-type specificity during metazoan development. Homeobox genes that regulate axial patterning and segmental identity (Hox/HOM genes) share a conserved clustered genomic organization. Mammals have four clusters that have likely arisen from the duplication of a single ancestral cluster. The number of Hox-type genes in other deuterostomes was estimated by using a polymerase chain reaction sampling method. Increased Hox gene complements are associated with the appearance of chordate and vertebrate characters. Our data suggest the presence of one Hox cluster in the acorn worm, a hemichordate; two Hox clusters in amphioxus, a cephalochordate; and three in the lamprey, a primitive vertebrate.
