Zebrafish mutations in Gli-mediated hedgehog signaling lead to lens transdifferentiation from the adenohypophysis anlage

Citation
H. Kondoh et al., Zebrafish mutations in Gli-mediated hedgehog signaling lead to lens transdifferentiation from the adenohypophysis anlage, MECH DEVEL, 96(2), 2000, pp. 165-174
Citations number
39
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Cell & Developmental Biology
Journal title
MECHANISMS OF DEVELOPMENT
ISSN journal
0925-4773 → ACNP
Volume
96
Issue
2
Year of publication
2000
Pages
165 - 174
Database
ISI
SICI code
0925-4773(200009)96:2<165:ZMIGHS>2.0.ZU;2-T
Abstract
it is known that the earliest lens marker delta-crystallin is expressed abu ndantly in Rathke's pouch of the chicken, suggesting a close relationship b etween the cell states of the adenohypophysis (pituitary) anlage and the ea rly lens. We show here that the zebrafish midline mutants you-too (yot) and iguana (igu) develop lenses from the adenohypophysis anlage. The early ade nohypophysis anlage of normal zebrafish expresses lim3 and six3 but in yot( ty119) mutants the anterior part of the anlage lacks lim3 expression, and i nstead produces a crystallin-expressing cell population which develops into a large lens structure expressing beta and gamma-crystallins, but is not a ssociated with retina tissues. Among the zebrafish mutants with midline def ects, midline lenses were observed in two mutant alleles of yot and an alle le of igu, but not in other mutants (syu, con, smh, dtr, umi, spi and lok). Two got mutant alleles with midline lenses likely encode dominant negative forms of the Gli2 protein which will interfere with transcriptional activa tion by other Gli proteins. The observation argues that overall inhibition of Shh-Gli signaling leads the adenohypophysis anlage to transdifferentiate into lens. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.