title: Cdk9/Cyclin T1 complex: a key player during the activation/differentiation process of normal lymphoid B cells.
abstract: Cdk9/Cyclin T1 complex is very important in controlling specific differentiative pathways of several cell types. Limited data are available regarding the expression of Cdk9/Cyclin T1 in hematopoietic and lymphoid tissues. Cdk9/Cyclin T1 expression seems to be related to particular stages of lymphoid differentiation/activation. In this study, we observed that the expression level of Cdk9/Cyclin T1 in vivo increases in memory B cells compared to naïve B cells, and in activated B cells, compared to non-activated ones. The expression level of the Cdk9/Cyclin T1 complex does not increase in cells induced to differentiate in vitro. In addition, we showed that Cdk9 interacts with E12 and E47, specifically activated during Germinal Center (GC) reaction. Taken together this data suggests an active role for the Cdk9/Cyclin T1 complex during lymphoid differentiation through germinal center reaction.
authors.affiliation: Department of Human Pathology and Oncology, University of Siena, Siena, Italy.
authors.forename: Giulia
authors.initials: G
authors.lastname: De Falco
authors.forename: Eleonora
authors.initials: E
authors.lastname: Leucci
authors.forename: Anna
authors.initials: A
authors.lastname: Onnis
authors.forename: Cristiana
authors.initials: C
authors.lastname: Bellan
authors.forename: Chiara
authors.initials: C
authors.lastname: Tigli
authors.forename: Stefan
authors.initials: S
authors.lastname: Wirths
authors.forename: Giovanna
authors.initials: G
authors.lastname: Cerino
authors.forename: Mario
authors.initials: M
authors.lastname: Cocco
authors.forename: Domenica
authors.initials: D
authors.lastname: Crupi
authors.forename: Antonio
authors.initials: A
authors.lastname: De Luca
authors.forename: Antonio
authors.initials: A
authors.lastname: Lanzavecchia
authors.forename: Piero
authors.initials: P
authors.lastname: Tosi
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Leoncini
authors.forename: Antonio
authors.initials: A
authors.lastname: Giordano
mesh_terms: D001402:B-Lymphocytes / Q000166:cytology* / Q000201:enzymology* / Q000378:metabolism; D002454:Cell Differentiation; D002470:Cell Survival; D056906:Cyclin T; D042863:Cyclin-Dependent Kinase 9 / Q000235:genetics / Q000378:metabolism*; D016213:Cyclins / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation; D018858:Germinal Center / Q000201:enzymology; D006801:Humans; D019169:Jurkat Cells; D008198:Lymph Nodes / Q000201:enzymology; D008213:Lymphocyte Activation / Q000276:immunology*; D018613:Microscopy, Confocal; D011485:Protein Binding; D021381:Protein Transport; D051820:TCF Transcription Factors / Q000378:metabolism; D058125:Transcription Factor 7-Like 1 Protein
chemical_list: C503684:CCNT1 protein, human; D056906:Cyclin T; D016213:Cyclins; D051820:TCF Transcription Factors; C544912:TCF7L1 protein, human; D058125:Transcription Factor 7-Like 1 Protein; D042863:Cyclin-Dependent Kinase 9