Perplexing Pax: from puzzle to paradigm.
Pax transcription factors are critical for the development of the central nervous system (CNS) where they have a biphasic role, initially dictating CNS regionalization, while later orchestrating differentiation of specific cell subtypes. While a plethora of expression, misexpression, and mutation studies lend support for this argument and clarify the importance of Pax genes in CNS development, less well understood, and more perplexing, is the continued Pax expression in the adult CNS. In this article we explore the mechanism of action of Pax genes in general, and while being cognizant of existing developmental data, we also draw evidence from (1) adult progenitor cells involved in regeneration and tissue maintenance, (2) specific expression patterns in fully differentiated adult cells, and (3) analysis of direct target genes functioning downstream of Pax proteins. From this, we present a more encompassing theory that Pax genes are key regulators of a cell's measured response to a dynamic environment.
Blake
Judith A
JA
School of Exercise Biomedical and Health Science, Edith Cowan University, Joondalup, Western Australia.
Thomas
Meghan
M
Thompson
Jennifer A
JA
White
Robert
R
Ziman
Melanie
M
D000818:Animals; D002454:Cell Differentiation; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D051761:Paired Box Transcription Factors / Q000235:genetics / Q000378:metabolism*
D051761:Paired Box Transcription Factors