Structure and expression of germline immunoglobulin γ3 heavy chain gene transcripts: implications for mitogen and lymphokine directed class-switching
| Autor: | Frederick W. Alt, Valerie Stewart, Beverly Gorham, Stuart Lutzker, Robert L. Coffman, Paul B. Rothman |
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| Rok vydání: | 1990 |
| Předmět: |
Lipopolysaccharides
Transcription Genetic Immunoglobulin gamma-Chains Molecular Sequence Data Immunology Biology Germline Mice Exon Animals Immunology and Allergy Interleukin 4 Messenger RNA Base Sequence Genes Immunoglobulin Lymphokine DNA General Medicine Molecular biology Gene Expression Regulation Immunoglobulin class switching Cell culture biology.protein Interleukin-4 Antibody Genes Switch Antibody Diversity |
| Zdroj: | International Immunology. 2:621-627 |
| ISSN: | 1460-2377 0953-8178 |
| Popis: | We have characterized the structure and expression of transcripts synthesized from the murine germline immunoglobulin gamma 3 heavy chain gene in certain B-lineage cells. The transcripts initiate upstream of the switch gamma 3 region, generating a 5' exon that is spliced to C gamma 3 exons. Expression of this germline transcript is induced when splenic B cells or A-MuLV-transformed pre-B cell lines are cultured in the presence of lipopolysaccharide (LPS). Addition of interleukin-4 (IL-4) to these lipopolysaccharide (LPS) cultures dramatically inhibits induction of the germline gamma 3 transcript. Induction of germline gamma 3 transcripts occurs before the increased accumulation of gamma 3-producing cells and VDJ-gamma 3 mRNA in cultures of splenic B cells. These data provide further evidence that germline CH transcriptional units are important components in the regulation of heavy chain class-switching. In addition, the pre-B cell lines that we describe represent the first example of permanent cell lines that regulate expression of the germline gamma locus in response to LPS plus IL-4 treatment in a manner analogous to normal B cells; therefore these lines should represent an excellent model system to further study the molecular mechanisms by which germline expression is regulated by these agents. |
| Databáze: | OpenAIRE |
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