miR-150, a microRNA expressed in mature B and T cells, blocks early B cell development when expressed prematurely.
MicroRNAs (miRNAs) are a family of approximately 22-nt noncoding RNAs that can posttranscriptionally regulate gene expression. Several miRNAs are specifically expressed in hematopoietic cells. Here we show that one such miRNA, miR-150, is mainly expressed in the lymph nodes and spleen and is highly up-regulated during the development of mature T and B cells; expression of miR-150 is sharply up-regulated at the immature B cell stage. Overexpression of miR-150 in hematopoietic stem cells, followed by bone marrow transplantation, had little effect on the formation of either mature CD8- and CD4-positive T cells or granulocytes or macrophages, but the formation of mature B cells was greatly impaired. Furthermore, premature expression of miR-150 blocked the transition from the pro-B to the pre-B stage. Our results indicate that miR-150 most likely down-regulates mRNAs that are important for pre- and pro-B cell formation or function, and its ectopic expression in these cells blocks further development of B cells.
Zhou
Beiyan
B
Whitehead Institute for Biomedical Research, Nine Cambridge Center, Cambridge, MA 02142, USA.
Wang
Stephanie
S
Mayr
Christine
C
Bartel
David P
DP
Lodish
Harvey F
HF
D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology* / Q000378:metabolism*; D005786:Gene Expression Regulation; D051379:Mice; D008810:Mice, Inbred C57BL; D035683:MicroRNAs / Q000235:genetics*; D013601:T-Lymphocytes / Q000166:cytology* / Q000378:metabolism*; D013997:Time Factors
D035683:MicroRNAs