Se. Quaggin et al., POD-1, A MESODERM-SPECIFIC BASIC-HELIX-LOOP-HELIX PROTEIN EXPRESSED IN MESENCHYMAL AND GLOMERULAR EPITHELIAL-CELLS IN THE DEVELOPING KIDNEY, Mechanisms of development, 71(1-2), 1998, pp. 37-48
Basic-helix-loop-helix (bHLH) proteins are transcriptional regulatory
proteins that govern cell fate determination and differentiation in a
variety of tissues. We have identified a novel bHLH protein, named Pod
-1, that belongs to a recently-described subfamily of bHLH proteins th
at have essential roles in the embryonic development of mesodermal tis
sues. In the adult human and mouse, Pod-1 was most highly expressed in
the kidney, lung and heart. In developing mouse embryos, Pod-1 was se
lectively expressed in mesenchymal cells at sites of epithelial-mesenc
hymal interaction in the kidney, lung, intestine and pancreas. Pod-1 w
as also expressed in visceral glomerular epithelial cells (podocytes)
in the kidney, and its expression coincided with the onset of podocyte
differentiation. The expression of Pod-1 in embryonic kidney explants
was inhibited using antisense oligonucleotides. Inhibition of Pod-1 e
xpression resulted in decreased mesenchymal cell condensation around t
he ureteric bud and a 40% decrease in ureteric branching. Pod-1 is the
first tissue-restricted basic-helix-loop-helix protein that has been
identified in the developing kidney where it may play a role in the re
gulation of morphogenetic events. (C) 1998 Elsevier Science Ireland Lt
d.