title: Cdk1 is a marker of proliferation in human lymphoid cells.
abstract: To better understand the relationship between the proliferation of human lymphoid cells and the expression of cdk1, a catalytic subunit of the histone H1 kinase (H1K), we examined its mRNA and protein content in 3 B-cell lines: Ramos, Reh-6 and IARC 963. Cells were elutriated according to their position in the cell cycle. Cell fractions were analyzed for cdk1 mRNA and protein cellular content by Northern blot and immunoblot, respectively, as well as for H1K activity. Both mRNA and protein amounts and H1K activity varied according to cell cycle phase, the lowest values being observed in G1-enriched fractions. For comparison, elutriated fractions were also tested for the expression of cdk2 and cdk4 proteins. Both showed some variations among fractions, but they were less clear than those of cdk1. We also tested 29 samples of lymphoid neoplastic and non-neoplastic tissues for proliferative activity (percentage of S and G2/M cells estimated by flow cytometry) and expression of cdk1, cdk2 and cdk4 proteins. We found a significant correlation between the percentage of cells in S or S + G2/M phases and cdk1 protein content but not cdk2 or cdk4 content. We conclude that cdk1 expression in human lymphoid cells varies during the cell cycle at both mRNA and protein levels.
authors.affiliation: Laboratoires de Cytologie Analytique, Université Claude-Bernard, Lyon, France.
authors.forename: D
authors.initials: D
authors.lastname: Wołowiec
authors.forename: P
authors.initials: P
authors.lastname: Deviller
authors.forename: D
authors.initials: D
authors.lastname: Simonin
authors.forename: C
authors.initials: C
authors.lastname: Souchier
authors.forename: R
authors.initials: R
authors.lastname: Rimokh
authors.forename: M
authors.initials: M
authors.lastname: Benchaib
authors.forename: P A
authors.initials: PA
authors.lastname: Bryon
authors.forename: M
authors.initials: M
authors.lastname: Ffrench
mesh_terms: D015415:Biomarkers; D002051:Burkitt Lymphoma; D016203:CDC2 Protein Kinase / Q000032:analysis / Q000096:biosynthesis*; D042846:CDC2-CDC28 Kinases; D002453:Cell Cycle; D002455:Cell Division; D002460:Cell Line; D051357:Cyclin-Dependent Kinase 2; D018844:Cyclin-Dependent Kinases / Q000032:analysis / Q000096:biosynthesis; D004273:DNA, Neoplasm / Q000032:analysis / Q000378:metabolism; D005434:Flow Cytometry; D015870:Gene Expression; D006801:Humans; D007700:Kinetics; D015448:Leukemia, B-Cell; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000378:metabolism / Q000473:pathology*; D008214:Lymphocytes; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000378:metabolism / Q000473:pathology*; D006656:Protamine Kinase / Q000032:analysis / Q000096:biosynthesis; D017346:Protein Serine-Threonine Kinases / Q000032:analysis / Q000096:biosynthesis; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D014407:Tumor Cells, Cultured
chemical_list: D015415:Biomarkers; D004273:DNA, Neoplasm; D012333:RNA, Messenger; D006656:Protamine Kinase; D017346:Protein Serine-Threonine Kinases; D016203:CDC2 Protein Kinase; D042846:CDC2-CDC28 Kinases; C495894:CDK2 protein, human; D051357:Cyclin-Dependent Kinase 2; D018844:Cyclin-Dependent Kinases