title: TM1 and TM2: two mutant alleles that constitute a genetic trait controlling thymocyte development.
abstract: Transgene insertion is instrumental to identifying genes with defined physiological functions. In this paper, we show that mice homozygous for either TM1 or TM2, two mutant alleles with distinct transgene insertions, exhibited embryo lethality, suggesting that these two alleles play essential roles in embryogenesis. Interestingly, although hemizygous TM1 or TM2 alone did not have obvious alteration in thymocyte development, together, they exhibited a compound effect on thymocyte development, blocking the development from CD4 and CD8 double-negative to double-positive stage of T cells. TM1 and TM2 mutations were mapped to chromosome regions 7E-F1 and 11B5-C, respectively, where we could not identify any known gene that was implicated in a similar function. Thus, TM1 and TM2 represent two novel alleles that define a genetic trait controlling thymocyte development.
authors.affiliation: Department of Microbiology, Columbia University College of Physicians and Surgeons, HHSC Rm6-611, 701 West 168th street, New York, NY 10032, USA.
authors.forename: Fang
authors.initials: F
authors.lastname: Huang
authors.forename: Mayumi
authors.initials: M
authors.lastname: Naramura
authors.forename: Virginia E
authors.initials: VE
authors.lastname: Papaioannou
authors.forename: Hua
authors.initials: H
authors.lastname: Gu
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D015704:CD4 Antigens / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000502:physiology; D016827:CD8 Antigens / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000502:physiology; D002454:Cell Differentiation; D033481:Chromosomes, Mammalian; D047108:Embryonic Development; D017930:Genes, Reporter; D051379:Mice; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D009154:Mutation; D013601:T-Lymphocytes / Q000166:cytology / Q000502:physiology*
chemical_list: D015704:CD4 Antigens; D016827:CD8 Antigens