Development 130, e802-e802 (2003)
Copyright © 2003 The Company of Biologists Limited
Diverging roles for gli genes in vertebrate development
Gli proteins regulate the transcription of Hedgehog (Hh) target genes
during vertebrate development, but can have different activities in different
organisms. For example, mouse Gli1 is not required for development,
whereas Gli2 is and activates Hh target genes; a function that Gli1
fulfils in frogs. So to investigate vertebrate gli gene conservation
and function, Karlstrom and colleagues turned to zebrafish, where they
discovered that the detour mutant is caused by loss of gli1
function (see p. 1549). Their
analyses of gli1 and gli2 functions in zebrafish show that
these genes are functionally divergent from their mouse orthologues: zebrafish
gli1 is an essential activator of Hh target genes, whereas
gli2 has a minor developmental role and both activates and represses
Hh targets. These surprising differences, the authors suggest, might underlie
divergent requirements for the genes in each species. Moreover, an
as-yet-unidentified zebrafish gli gene might compensate for reduced
Gli2 activity.
Related articles in Development:
- Genetic analysis of zebrafish gli1 and gli2 reveals divergent requirements for gli genes in vertebrate development
- Rolf O. Karlstrom, Oksana V. Tyurina, Atsushi Kawakami, Noriyuki Nishioka, William S. Talbot, Hiroshi Sasaki, and Alexander F. Schier
Development 2003 130: 1549-1564.
[Abstract]
[Full Text]