As a source of transplantable stem cells, the CD34^＋ subpopulation in human umbilical cord blood （HUCB） has been used extensively to treat some hematopoietic system diseases. However, whether CD34^＋ cells hold th...As a source of transplantable stem cells, the CD34^＋ subpopulation in human umbilical cord blood （HUCB） has been used extensively to treat some hematopoietic system diseases. However, whether CD34^＋ cells hold the therapeutic potential to cerebral ischemia is unknown. The purpose of this study was to observe the recovery of neural function after transplantation of CD34^＋ cells derived from HUCB into ischemic cerebral tissue in rats.展开更多
Background Sam68 plays an important role as a multiple functional RNA binding nuclear protein in cell cycle progress, RNA usage, signal transduction, and tyrosine phosphorylation by Src during mitosis. However, its pr...Background Sam68 plays an important role as a multiple functional RNA binding nuclear protein in cell cycle progress, RNA usage, signal transduction, and tyrosine phosphorylation by Src during mitosis. However, its precise impact on these essential cellular functions remains unclear. The purpose of this study is to further elucidate Sam68 functions in RNA metabolism, signal transduction regulation of cell growth and cell proliferation in DT40 cell line. Methods By using gene targeting method, we isolated a mutation form of Sam68 in DT40 cells and described its effect on cell growth process and signal transduction. Southern, Northern, and Western blot, phosphorylation and flow-cytometric analyses were performed to investigate the Sam68 functions. Results A slower growth rate （2.1 hours growth elongation） and longer S phase （1.7 hours elongation） was observed in the Sam68 mutant cells. Serum depletion resulted in increased amounts of dead cells, and expansion of S phase in mutant cells. Upon B cell cross-linking, the maximal level of tyrosine phosphorylation on BLNK was observed to be significantly lower in mutant cells.Conclusions The proline rich domain of Sam68 is involved in cell growth control by modulating the function of mRNAs in S phase or earlier and the functions as an adaptor molecule in B cell signal transduction pathways.展开更多
基金This work was supported by a grant from the Natural Science Foundation of Hebei Province (No. 302508).
文摘As a source of transplantable stem cells, the CD34^＋ subpopulation in human umbilical cord blood （HUCB） has been used extensively to treat some hematopoietic system diseases. However, whether CD34^＋ cells hold the therapeutic potential to cerebral ischemia is unknown. The purpose of this study was to observe the recovery of neural function after transplantation of CD34^＋ cells derived from HUCB into ischemic cerebral tissue in rats.
文摘Background Sam68 plays an important role as a multiple functional RNA binding nuclear protein in cell cycle progress, RNA usage, signal transduction, and tyrosine phosphorylation by Src during mitosis. However, its precise impact on these essential cellular functions remains unclear. The purpose of this study is to further elucidate Sam68 functions in RNA metabolism, signal transduction regulation of cell growth and cell proliferation in DT40 cell line. Methods By using gene targeting method, we isolated a mutation form of Sam68 in DT40 cells and described its effect on cell growth process and signal transduction. Southern, Northern, and Western blot, phosphorylation and flow-cytometric analyses were performed to investigate the Sam68 functions. Results A slower growth rate （2.1 hours growth elongation） and longer S phase （1.7 hours elongation） was observed in the Sam68 mutant cells. Serum depletion resulted in increased amounts of dead cells, and expansion of S phase in mutant cells. Upon B cell cross-linking, the maximal level of tyrosine phosphorylation on BLNK was observed to be significantly lower in mutant cells.Conclusions The proline rich domain of Sam68 is involved in cell growth control by modulating the function of mRNAs in S phase or earlier and the functions as an adaptor molecule in B cell signal transduction pathways.
