title: In vivo overexpression of Dad1, the defender against apoptotic death-1, enhances T cell proliferation but does not protect against apoptosis.
abstract: The Dad1 protein has been shown to play a role in prevention of apoptosis in certain cell types. Dad1 is also a subunit of the oligosaccharyltransferase enzyme complex that initiates N-linked glycosylation. It is encoded by a gene located adjacent to the TCR alpha and delta genes on mouse chromosome 14. We have investigated the role of Dad1 during T cell development and activation. We observe that endogenous Dad1 levels are modulated during T cell development to reach maximal expression in mature thymocytes. Transgenic mice that overexpress Dad1 in both the thymus and peripheral immune system have been generated. Apoptosis of thymocytes from such mice is largely unaffected, but peripheral T cells display hyperproliferation in response to stimuli. Therefore, the linkage between the TCR and Dad1 genes may have important consequences for T cell function.
authors.affiliation: Division of Immunology, Cancer Research Laboratory, Department of Molecular and Cell Biology, University of California, Berkeley 94720, USA.
authors.forename: N A
authors.initials: NA
authors.lastname: Hong
authors.forename: N H
authors.initials: NH
authors.lastname: Kabra
authors.forename: S N
authors.initials: SN
authors.lastname: Hsieh
authors.forename: D
authors.initials: D
authors.lastname: Cado
authors.forename: A
authors.initials: A
authors.lastname: Winoto
mesh_terms: D000276:Adjuvants, Immunologic / Q000096:biosynthesis* / Q000502:physiology*; D000818:Animals; D017209:Apoptosis / Q000235:genetics / Q000276:immunology*; D051017:Apoptosis Regulatory Proteins; D002478:Cells, Cultured; D008213:Lymphocyte Activation / Q000235:genetics / Q000276:immunology*; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck) / Q000235:genetics; D008565:Membrane Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology*; D051379:Mice; D008822:Mice, Transgenic; D011401:Promoter Regions, Genetic / Q000276:immunology; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D013950:Thymus Gland / Q000166:cytology / Q000378:metabolism; D019076:Transgenes / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D051017:Apoptosis Regulatory Proteins; C489987:Dad1 protein, mouse; D008565:Membrane Proteins; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck)