title: Tsg101 is essential for cell growth, proliferation, and cell survival of embryonic and adult tissues.
abstract: Tumor susceptibility gene 101 (Tsg101) was identified in a random mutagenesis screen for potential tumor suppressors in NIH 3T3 cells. Altered transcripts of this gene have been detected in sporadic breast cancers and many other human malignancies. However, the involvement of this gene in neoplastic transformation and tumorigenesis is still elusive. Using gene targeting, we generated genetically engineered mice with a floxed allele of Tsg101. We investigated essential functions of this gene in vivo and examined whether the loss of function of Tsg101 results in tumorigenesis. Conventional knockout mice were generated through Cre-mediated excision of the first coding exon in the germ line of mouse mammary tumor virus (MMTV)-Cre transgenic mice. The complete ablation of Tsg101 in the developing embryo resulted in death around implantation. In contrast, mammary gland-specific knockout mice developed normally but were unable to nurse their young as a result of impaired mammogenesis during late pregnancy. Neither heterozygous null mutants nor somatic knockout mice developed mammary tumors after a latency of 2 years. The Cre-mediated deletion of Tsg101 in primary cells demonstrated that this gene is essential for the growth, proliferation, and survival of mammary epithelial cells. In summary, our results suggest that Tsg101 is required for normal cell function of embryonic and adult tissues but that this gene is not a tumor suppressor for sporadic forms of breast cancer.
authors.affiliation: Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha 68198-6805, USA. kuwagner@unmc.edu
authors.forename: Kay-Uwe
authors.initials: KU
authors.lastname: Wagner
authors.forename: Andrea
authors.initials: A
authors.lastname: Krempler
authors.forename: Yongyue
authors.initials: Y
authors.lastname: Qi
authors.forename: KyungRan
authors.initials: K
authors.lastname: Park
authors.forename: MaLinda D
authors.initials: MD
authors.lastname: Henry
authors.forename: Aleata A
authors.initials: AA
authors.lastname: Triplett
authors.forename: Gregory
authors.initials: G
authors.lastname: Riedlinger
authors.forename: Edmund B
authors.initials: EB
authors.lastname: Rucker III
authors.forename: Lothar
authors.initials: L
authors.lastname: Hennighausen
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000235:genetics; D002455:Cell Division / Q000235:genetics; D002470:Cell Survival / Q000235:genetics; D004268:DNA-Binding Proteins / Q000502:physiology*; D004622:Embryo, Mammalian / Q000166:cytology* / Q000502:physiology; D056827:Endosomal Sorting Complexes Required for Transport; D004847:Epithelial Cells / Q000502:physiology; D005260:Female; D005313:Fetal Death / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D007775:Lactation Disorders / Q000235:genetics; D008321:Mammary Glands, Animal / Q000002:abnormalities / Q000166:cytology* / Q000502:physiology*; D008325:Mammary Neoplasms, Experimental / Q000235:genetics; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic; D014157:Transcription Factors / Q000502:physiology*; D000099177:Tsg101 Protein
chemical_list: D004268:DNA-Binding Proteins; D056827:Endosomal Sorting Complexes Required for Transport; D014157:Transcription Factors; D000099177:Tsg101 Protein