Details

Autor(en) / Beteiligte

• Quesenberry, Peter J.
• Iscove, Norman N.
• Cooper, Cathleen
• Brady, Gerard
• Newburger, Peter E.
• Stein, Gary S.
• Stein, Janet S.
• Reddy, G. Prem Veer
• Pearson-White, Sonia

Titel

Expression of basic helix-loop-helix transcription factors in explant hematopoietic progenitors

Ist Teil von

• Journal of cellular biochemistry, 1996-06, Vol.61 (3), p.478-488

Ort / Verlag

Hoboken: Wiley Subscription Services, Inc., A Wiley Company

Erscheinungsjahr

1996

Quelle

MEDLINE

Beschreibungen/Notizen

• The basic helix‐loop‐helix (bHLH) transcription factors form heterodimers and control steps in cellular differentiation. We have studied four bHLH transcription factors, SCL, lyl‐1, E12/E47, and Id‐1, in individual lineage‐defined progenitors and hematopoietic growth factor—dependent cell lines, evaluating mRNA expression and the effects of growth factors and cell cycle phase on this expression. Single lineage‐defined progenitors selected from early murine colony starts and grown under permissive conditions were analyzed by RT‐PCR. SCL and E12/E47 were expressed in the vast majority of tri‐, bi‐, and unilineage progenitors of erythroid, macrophage, megakaryocyte, and neutrophil lineages. Expression for E12/E47 was not seen in unilineage megakaryocyte and erythroid or bilineage neutrophil/mast cell progenitors. Lyl‐1 showed a more restricted pattern of expression, although expression was seen in some bi‐ and unilineage progenitors. No expression was detected in erythroid, erythroid‐megakaryocyte‐macrophage, macrophage‐neutrophil, macrophage, or megakaryocytic progenitors. Id‐1, an inhibitory bHLH transcription factor, was also widely expressed in all bi‐ and unilineage progenitors; only the trilineage erythroid‐megakaryocyte‐macrophage progenitors failed to show expression. Expression of these factors within a progenitor class was generally heterogeneous, with some progenitors showing expression and some not. This was seen even when two sister cells from the same colony start were analyzed. Id‐1, but not E12/E47, mRNA was increased in FDC‐P1 and MO7E hematopoietic cell lines after exposure to IL‐3 or GM‐CSF, Id‐1, E12, and lyl‐1 showed marked variation at different points in cell cycle in isoleucine‐synchronized FDC‐P1 cells. These results suggest that SCL, lyl‐1, E12/E47, and Id‐1 are important in hematopoietic progenitor cell regulation, and that their expression in hematopoietic cells varies in response to cytokines and/or during transit through cell cycle. © 1996 Wiley‐Liss, Inc.