Ectopic expression of A-myb in transgenic mice causes follicular hyperplasia and enhanced B lymphocyte proliferation
AUTOR(ES)
DeRocco, Susan E.
FONTE
The National Academy of Sciences of the USA
RESUMO
The A-myb gene is a transcription factor that shares structural and functional similarities with the v-myb oncogene. To date, v-myb is the only myb gene directly implicated in tumorigenesis, a property attributed to its transactivating ability. Recent studies have demonstrated that A-myb, like v-myb, is a potent transcriptional activator, raising the possibility that A-myb may also participate in oncogenesis. To test this hypothesis, we generated fusion constructs that contained the human A-myb cDNA under control of the mouse metallothionein promoter and the mouse mammary tumor virus long terminal repeat. These constructs were inserted into the germ line of mice, and the functional consequences of ectopic A-myb expression were examined. Although transgene expression was detected in a wide range of tissues, abnormalities were confined primarily to hematopoietic tissues. After a 9-month latency, A-myb transgenic mice developed hyperplasia of the spleen and lymph nodes. Enlarged tissues contained a polyclonally expanded B lymphocyte population that expressed a germinal center-cell phenotype. Transgenic B lymphocytes showed increased DNA synthesis in response to low dose mitogen stimulation, suggesting that A-myb may contribute to hyperplasia by increasing the rate of B cell proliferation.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=20353Documentos Relacionados
- Isolation of human cDNA clones of myb-related genes, A-myb and B-myb.
- Isolation of human cDNA clones of myb-related genes, A-myb and B-myb
- Overexpression of A-myb induces basic fibroblast growth factor-dependent proliferation of chicken neuroretina cells.
- Mouse A-myb encodes a trans-activator and is expressed in mitotically active cells of the developing central nervous system, adult testis and B lymphocytes.
- Ectopic expression of the agouti gene in transgenic mice causes obesity, features of type II diabetes, and yellow fur.