Expression of cell cycle-related genes with cytokine-induced cell cycle progression of primitive hematopoietic stem cells.
Primitive marrow lineage-negative rhodamine low and Hoechst low (LRH) stem cells isolated on the basis of quiescence respond to the cytokines thrombopoietin, FLT3L, and steel factor by synchronously progressing through cell cycle. We have now profiled the mRNA expression, as determined by real-time RT-PCR, of 47 hematopoietic or cell cycle-related genes, focusing on the variations in the cell cycle regulators with cycle transit. LRH stem cells, at isolation, showed expression of all interrogated genes, but at relatively low levels. In our studies, there was a good deal of consistency with regard to cell cycle regulatory genes involved in the G1/S progression point of LRH murine stem cells. The observed pattern of expression of cyclin A2 is consistent with actions at these phases of cell cycle. Minimal elevations were seen at 16 h with higher elevations at 24, 32, 40, and 48 h times encompassing S, G2, and M phases. CDK2 expression pattern was also consistent with a role in G1/S transition with a modest elevation at 24 h and more substantial elevation at 32 h. The observed pattern of expression of cyclin F mRNA with marked elevations at 16-40 h was also consistent with actions in S and G2 phases. Cyclin D1 expression pattern was less consistent with its known role in G1 progression. The alterations in multiple other cell cycle regulators were consistent with previous information obtained in other cell systems. The cycle regulatory mechanics appears to be preserved across broad ranges of cell types.
Rhode Island Hospital and the Brown Medical School, Division of Hematology/Oncology, Department of Medicine, Providence, Rhode Island 02903, USA. pquesenberry@lifespan.org
Peter J
PJ
Quesenberry
Gerri J
GJ
Dooner
Michael Del
MD
Tatto
Gerald A
GA
Colvin
Kevin
K
Johnson
Mark S
MS
Dooner
D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000818:Animals; D002453:Cell Cycle / Q000187:drug effects / Q000235:genetics; D019070:Cell Lineage; D002478:Cells, Cultured; D051357:Cyclin-Dependent Kinase 2 / Q000235:genetics; D016213:Cyclins / Q000235:genetics; D015870:Gene Expression; D006410:Hematopoiesis / Q000187:drug effects / Q000235:genetics; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008565:Membrane Proteins / Q000494:pharmacology; D051379:Mice; D012235:Rhodamines; D019089:Stem Cell Factor / Q000494:pharmacology; D013926:Thrombopoietin / Q000494:pharmacology
D000276:Adjuvants, Immunologic; D016213:Cyclins; D008565:Membrane Proteins; D012235:Rhodamines; D019089:Stem Cell Factor; C084881:flt3 ligand protein; D013926:Thrombopoietin; D051357:Cyclin-Dependent Kinase 2