title: Disruption of the PU.1 gene in chicken B lymphoma DT40 cells and its effect on reported target gene expression.
abstract: Using avian B lymphoma-derived DT40 cells, we disrupted a gene encoding the transcription factor PU.1. The mutant mRNA codes for a protein incapable of functioning as a transcription factor because of the deletion of the protein's DNA-binding domain. The absence of a functional PU.1 protein in the mutant cells was confirmed by Western blotting and electrophoretic mobility shift assay, thereby demonstrating that PU.1 was not essential for the proliferation of DT40 cells. An examination of the expression of several genes known to be PU.1 protein targets revealed almost the same levels of Ig-beta and Ig lambda L chain mRNA in mutant cells as in wild-type cells, indicating that the PU.1 protein plays no essential role in the transcription of these genes. Mutant cell doubling times 1.3 times longer than those of wild-type cells confirmed the PU.1 protein to be involved in the proliferation of B lymphocytes.
authors.affiliation: Department of Life Science, College of Science, Rikkyo University, Tokyo 171-8501, Toshima-ku, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Matsudo
authors.forename: Akira
authors.initials: A
authors.lastname: Otsuka
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Ozawa
authors.forename: Masao
authors.initials: M
authors.lastname: Ono
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism; D001665:Binding Sites / Q000235:genetics; D051925:CD79 Antigens; D002455:Cell Division / Q000235:genetics; D045744:Cell Line, Tumor; D002645:Chickens; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D007146:Immunoglobulin lambda-Chains / Q000235:genetics / Q000378:metabolism; D007148:Immunoglobulin mu-Chains / Q000235:genetics / Q000378:metabolism; D016393:Lymphoma, B-Cell / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D008969:Molecular Sequence Data; D009154:Mutation; D011485:Protein Binding; D011518:Proto-Oncogene Proteins / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism; D000099232:Proto-Oncogene Protein Spi-1
chemical_list: D015703:Antigens, CD; D051925:CD79 Antigens; D018076:DNA, Complementary; D007146:Immunoglobulin lambda-Chains; D007148:Immunoglobulin mu-Chains; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D015534:Trans-Activators; D000099232:Proto-Oncogene Protein Spi-1