The NK homeobox gene cluster predates the origin of Hox genes

Larroux, C., Fahey, B., Degnan, S. M., Adamski, M., Rokhsar, D. S. and Degnan, B. M. (2007) The NK homeobox gene cluster predates the origin of Hox genes. Current Biology, 17 8: 706-710. doi:10.1016/j.cub.2007.03.008


Author Larroux, C.
Fahey, B.
Degnan, S. M.
Adamski, M.
Rokhsar, D. S.
Degnan, B. M.
Title The NK homeobox gene cluster predates the origin of Hox genes
Journal name Current Biology   Check publisher's open access policy
ISSN 0960-9822
Publication date 2007-01-01
Sub-type Article (original research)
DOI 10.1016/j.cub.2007.03.008
Volume 17
Issue 8
Start page 706
End page 710
Total pages 5
Editor North, G.
Place of publication Cambridge, USA
Publisher Cell Press
Language eng
Subject C1
270208 Molecular Evolution
770302 Living resources (incl. impacts of fishing on non-target species)
Abstract Hox and other Antennapedia (ANTP)-like homeobox gene subclasses-ParaHox, EHGbox, and NK-likecontribute to key developmental events in bilaterians [1-4]. Evidence of physical clustering of ANTP genes in multiple animal genomes [4-9] suggests that all four subclasses arose via sequential cis-duplication events. Here, we show that Hox genes'origin occurred after the divergence of sponge and eumetazoan lineages and occurred concomitantly with a major evolutionary transition in animal body-plan complexity. By using whole genome information from the demosponge Amphimedon queenslandica, we provide the first conclusive evidence that the earliest metazoans possessed multiple NK-like genes but no Hox, ParaHox, or EHGbox genes. Six of the eight NK-like genes present in the Amphimedon genome are clustered within 71 kb in an order akin to bilaterian NK clusters. We infer that the NK cluster in the last common ancestor to sponges, cnidarians, and bilaterians consisted of at least five genes. It appears that the ProtoHox gene originated from within this ancestral cluster after the divergence of sponge and eumetazoan lineages. The maintenance of the NK cluster in sponges and bilaterians for greater than 550 million years is likely to reflect regulatory constraints inherent to the organization of this ancient cluster.
Keyword Biochemistry & Molecular Biology
Antp-class
Sea-anemone
Evolution
Sponge
Multicellularity
Diversification
Expression
Demosponge
Phylogeny
Amphioxus
Q-Index Code C1
Q-Index Status Confirmed Code

 
Versions
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 90 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 100 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Tue, 19 Feb 2008, 02:55:53 EST