Early stages of induction of anterior head ectodermal properties in Xenopus embryos are mediated by transcriptional cofactor ldb1. Issue 12 (18th October 2014)

• Record Type: Journal Article
• Authors: Plautz, Carol Zygar; Zirkle, Brett E.; Deshotel, Malia J.; Grainger, Robert M.
• Is Part Of: Developmental dynamics. Volume 243:Issue 12(2014:Dec.)
• Page Start: 1606
• Page End: 1618
• Publication Date: 2014-10-18
• Subjects: Morphogenesis -- Periodicals; Anatomy -- Periodicals; Anatomie -- Périodiques; Biologie du développement -- Périodiques; 571.833
• DOI: 10.1002/dvdy.24193
• Languages: English
• ISSNs: 1058-8388

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p> <underline>Background</underline>: Specific molecules involved in early inductive signaling from anterior neural tissue to the placodal ectoderm to establish a lens‐forming bias, as well as their regulatory factors, remain largely unknown. In this study, we sought to identify and characterize these molecules. <underline>Results</underline>: Using an expression cloning strategy to isolate genes with lens‐inducing activity, we identified the transcriptional cofactor <italic>ldb1</italic>. This, together with evidence for its nuclear dependence, suggests its role as a regulatory factor, not a direct signaling molecule. We propose that <italic>ldb1</italic> mediates induction of early lens genes in our functional assay by transcriptional activation of lens‐inducing signals. Gain‐of‐function assays demonstrate that the inductive activity of the anterior neural plate on head ectodermal structures can be augmented by <italic>ldb1</italic>. Loss‐of‐function assays show that knockdown of <italic>ldb1</italic> leads to decreased expression of early lens and retinal markers and subsequently to defects in eye development. <underline>Conclusions</underline>: The functional cloning, expression pattern, overexpression, and knockdown data show that an <italic>ldb1</italic>‐regulated mechanism acts as an early signal for <italic>Xenopus</italic> lens induction. <italic>Developmental Dynamics 243:1606–1618, 2014</italic>. © 2014 Wiley Periodicals, Inc.</p> </abstract>