Format

Send to

Choose Destination
See comment in PubMed Commons below
Dev Biol. 2011 Jan 15;349(2):395-405. doi: 10.1016/j.ydbio.2010.10.028. Epub 2010 Oct 28.

Pitx2 is an upstream activator of extraocular myogenesis and survival.

Author information

1
Department of Ophthalmology & Visual Science, University of Michigan Medical School, Ann Arbor, MI 48105, USA.

Abstract

The transcription factors required to initiate myogenesis in branchial arch- and somite-derived muscles are known, but the comparable upstream factors required during extraocular muscle development have not been identified. We show Pax7 is dispensable for extraocular muscle formation, whereas Pitx2 is cell-autonomously required to prevent apoptosis of the extraocular muscle primordia. The survival requirement for Pitx2 is stage-dependent and ends following stable activation of genes for the muscle regulatory factors (e.g. Myf5, MyoD), which is reduced in the absence of Pitx2. Further, PITX2 binds and activates transcription of the Myf5 and MyoD promoters, indicating these genes are direct targets. Collectively, these data demonstrate that PITX2 is required at several steps in the development of extraocular muscles, acting first as an anti-apoptotic factor in pre-myogenic mesoderm, and subsequently to activate the myogenic program in these cells. Thus, Pitx2 is the first demonstrated upstream activator of myogenesis in the extraocular muscles.

PMID:
21035439
PMCID:
PMC3019256
DOI:
10.1016/j.ydbio.2010.10.028
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science Icon for PubMed Central
    Loading ...
    Support Center