Rearrangement and diversification of immunoglobulin light-chain genes in lymphoid cells transformed by reticuloendotheliosis virus.
Avian lymphoid cells transformed by reticuloendotheliosis virus (REV-T) serve as a model to analyze the mechanism by which B-cell differentiation and antibody diversification occur in birds. Immunoglobulin light-chain gene rearrangements, diversification, and expression were analyzed in 72 independently derived REV-T-transformed cell lines. Lymphoid cells transformed as the result of expression of the v-rel oncogene were divided into two distinct groups based on light-chain gene rearrangements. The status of the light-chain gene loci in these REV-T-transformed cell lines was determined in part by the ages of the chickens whose spleen cells were transformed. In embryonic spleen cell lines transformed by the v-rel oncogene, rearrangements were not detected, even after prolonged culture in vitro, indicating that these cells are arrested in B-cell differentiation. REV-T transformants derived from spleens obtained from chickens 2 weeks old or older, however, had at least one light-chain allele rearranged. All of the cell lines analyzed which exhibited rearranged light-chain genes contained light-chain transcripts, and most of the REV-T-transformed cells which displayed light-chain rearrangements expressed immunoglobulin protein. REV-T, therefore, transforms B-lymphoid cells at phenotypically different stages of development. Many REV-T-transformed cells undergo immunoglobulin chain gene rearrangements during prolonged propagation in vitro. Most of the cell lines which rearrange their light-chain alleles also undergo diversification during cultivation in vitro. Light-chain diversification occurs during or after the rearrangement event.
Zhang
J Y
JY
Department of Microbiology, University of Texas, Austin 78712.
Bargmann
W
W
Bose
H R
HR
D000375:Aging / Q000235:genetics; D000818:Animals; D000916:Antibody Diversity / Q000235:genetics*; D001483:Base Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D002461:Cell Line, Transformed; D002472:Cell Transformation, Viral / Q000235:genetics*; D002645:Chickens; D015870:Gene Expression; D015328:Gene Rearrangement, B-Lymphocyte, Light Chain; D005803:Genes, Immunoglobulin; D008214:Lymphocytes / Q000276:immunology*; D008969:Molecular Sequence Data; D009857:Oncogenes; D010641:Phenotype; D001356:Reticuloendotheliosis virus / Q000502:physiology*; D012190:Retroviridae / Q000502:physiology*; D013154:Spleen / Q000378:metabolism; D014158:Transcription, Genetic