Identification and characterization of subpopulations of Pax3 and Pax7 expressing cells in developing chick somites and limb buds.
Pax3 and Pax7 are closely related paired-boxed family transcription factors that are known to play important roles in embryonic and adult myogenesis. Previous reports describing the expression of Pax3 and Pax7 transcripts reveal expression in many overlapping domains. In this manuscript, we extend these studies by examining the protein expression profiles for Pax3 and Pax7 in developing chick somites and limbs with cellular resolution. Our studies show the existence of distinct subpopulations of cells in the somite and developing limb that are defined by the relative expression levels of Pax3 and Pax7. We also show that Pax3 and Pax7 negatively regulate each other's expression in the dermomyotome, thus providing a possible mechanism for the maintenance of observed expression patterns in the dermomyotome. Further characterization of Pax3- and/or Pax7-positive cells in the dermomyotome and myotome with respect to proliferation and differentiation reveals subpopulations of cells with distinct properties.
Department of Biology, San Francisco State University, San Francisco, California 94132, USA.
Lisa M
LM
Galli
Sara R
SR
Knight
Tiffany L
TL
Barnes
Allison K
AK
Doak
Rachel S
RS
Kadzik
Laura W
LW
Burrus
D000818:Animals; D049109:Cell Proliferation; D002642:Chick Embryo; D002645:Chickens; D007150:Immunohistochemistry; D018878:Limb Buds / Q000166:cytology / Q000196:embryology / Q000378:metabolism*; D018613:Microscopy, Confocal; D051763:PAX7 Transcription Factor / Q000096:biosynthesis*; D051761:Paired Box Transcription Factors / Q000096:biosynthesis*; D019170:Somites / Q000166:cytology / Q000196:embryology / Q000378:metabolism*
D051763:PAX7 Transcription Factor; D051761:Paired Box Transcription Factors