ISSN:
0265-9247
Keywords:
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
In vertebrate development, the HOX genes act to specify cell identity along much of the anterior-posterior axis of the embryonic central nervous system. In all vertebrates examined to date, the vitamin A metabolite retinoic acid is implicated in the patterning of the anterior posterior axis and the induction of HOX gene expression. Two recent papers have extended the study of retinoic acid induction of HOX genes to the closest relatives of the vertebrates, amphioxus and tunicates(1,2). In both these species, exogenous retinoic acid is able to induce ectopic expression of HOX 1 genes in the anterior central nervous system. This suggests that retinoic acid control of anterior-posterior axis formation and HOX induction is not specific to vertebrates. However, in the more distantly related echinoderms and arthropods, retinoic acid does not seem to act in the same way. Thus the role of retinoic acid in anterior-posterior axis specification may be a chordate innovation, perhaps linked to the evolution of another chordate character, the dorsal neural tube.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/bies.950180803
