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Updated: Jul 14, 2026
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Zinc-finger Nuclease Enhanced Gene Targeting in Human Embryonic Stem Cells
Published on: August 23, 2014
Sequential expression and redundancy of Pitx2 and Pitx3 genes during muscle development.
Aurore L'Honoré1, Vincent Coulon, Alexandre Marcil
1Laboratoire de génétique moléculaire, Institut de Recherches Cliniques de Montréal (IRCM), 110, avenue des Pins Ouest, Montréal, QC, Canada H2W 1R7.
Developmental Biology
|June 2, 2007
Summary
Pitx2 and Pitx3 transcription factors are newly identified as important for muscle development. While Pitx3 deficiency is compensated by Pitx2, suggesting overlapping roles in myogenesis.
Area of Science:
- Molecular Biology
- Developmental Biology
- Genetics
Background:
- Muscle development relies on transcription factors like MRFs, Pax, and Six genes.
- The roles of Pitx2 and Pitx3 in myogenesis were previously uncharacterized.
Purpose of the Study:
- To investigate the expression patterns of Pitx2 and Pitx3 during muscle development.
- To determine the functional significance of Pitx3 in myogenesis and its relationship with Pitx2.
Main Methods:
- Analysis of Pitx2 and Pitx3 expression during embryonic and postnatal muscle development.
- Generation and analysis of Pitx3 mutant mice to assess muscle development phenotypes.
Main Results:
- Pitx2 is expressed in early muscle progenitor cells, while Pitx3 expression begins during myoblast differentiation and persists in skeletal muscles.
- Pitx3 mutant mice exhibit normal muscle development, with Pitx2 expression compensating for the Pitx3 deficiency.
- Pitx2 expression is maintained in all skeletal muscles even in the absence of Pitx3.
Conclusions:
- Pitx genes play a significant role in myogenesis.
- Pitx2 and Pitx3 exhibit partially redundant functions in skeletal muscle development.
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