title: Bax alpha perturbs T cell development and affects cell cycle entry of T cells.
abstract: Bax alpha can heterodimerize with Bcl-2 and Bcl-X(L), countering their effects, as well as promoting apoptosis on overexpression. We show that bax alpha transgenic mice have greatly reduced numbers of mature T cells, which results from an impaired positive selection in the thymus. This perturbation in positive selection is accompanied by an increase in the number of cycling thymocytes. Further to this, mature T cells overexpressing Bax alpha have lower levels of p27Kip1 and enter S phase more rapidly in response to interleukin-2 stimulation than do control T cells, while the converse is true of bcl-2 transgenic T cells. These data indicate that apoptotic regulatory proteins can modulate the level of cell cycle-controlling proteins and thereby directly impact on the cell cycle.
authors.affiliation: Division of Molecular Genetics, The Netherlands Cancer Institute, Amsterdam.
authors.forename: H J
authors.initials: HJ
authors.lastname: Brady
authors.forename: G
authors.initials: G
authors.lastname: Gil-Gómez
authors.forename: J
authors.initials: J
authors.lastname: Kirberg
authors.forename: A J
authors.initials: AJ
authors.lastname: Berns
mesh_terms: D000818:Animals; D017209:Apoptosis; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D016196:S Phase; D013601:T-Lymphocytes / Q000166:cytology*; D013950:Thymus Gland / Q000166:cytology; D051028:bcl-2-Associated X Protein
chemical_list: C494827:Bax protein, mouse; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein