Wnts are secreted lipid-modified signaling proteins that influence multiple processes ranging from cell proliferation and differentiation, fate decisions, apoptosis, axial polarity and axonal guidance to stem cell los...Wnts are secreted lipid-modified signaling proteins that influence multiple processes ranging from cell proliferation and differentiation, fate decisions, apoptosis, axial polarity and axonal guidance to stem cell loss, kidney and reproductive tract defects. Activation of Wnt signalling in many tissues has also been associated with cancer. In many eukaryotes, expression of nuclear-encoded mRNA can be strongly inhibited by the presence of a small double-stranded RNA corresponding to exon sequences in the mRNA. In this study, human Wnt9a was cloned from undifferentiated hES cells. The results of immunohistochemistry showed that Wnt9a protein was expressed in undifferentiated hES cells, pAVU6＋27 vectors were used to construct the siRNA expression vectors for human Wnt9a One kind of small interfering RNA inserts was designed, synthesized and tested for human Wnt9a. The results of in situ hybridization demonstrated that Wntga signal was dramatically reduced in the cells transfected with U6＋27/siWnt9a compared to the untransfected cells. The results of flow cytometry analysis showed that the human breast cancer MCF-7 cells proliferation was promoted after lowering the expression of human Wnt9a by RNAi, but inhibited after over-expression of human Wnt9a. All those suggest the expression level of human Wnt9a may play a role in adjusting the rate of cell proliferation ofhES and MCF-7 cells.展开更多
基金Acknowledgment This work was supported by grants from the National Nature Science Foundation of China （No.31071091 No.30971570 No.31171196） and Department of Education Key Project of HuNan Province, China （NO：09A035 and NO：06C370）.
文摘Wnts are secreted lipid-modified signaling proteins that influence multiple processes ranging from cell proliferation and differentiation, fate decisions, apoptosis, axial polarity and axonal guidance to stem cell loss, kidney and reproductive tract defects. Activation of Wnt signalling in many tissues has also been associated with cancer. In many eukaryotes, expression of nuclear-encoded mRNA can be strongly inhibited by the presence of a small double-stranded RNA corresponding to exon sequences in the mRNA. In this study, human Wnt9a was cloned from undifferentiated hES cells. The results of immunohistochemistry showed that Wnt9a protein was expressed in undifferentiated hES cells, pAVU6＋27 vectors were used to construct the siRNA expression vectors for human Wnt9a One kind of small interfering RNA inserts was designed, synthesized and tested for human Wnt9a. The results of in situ hybridization demonstrated that Wntga signal was dramatically reduced in the cells transfected with U6＋27/siWnt9a compared to the untransfected cells. The results of flow cytometry analysis showed that the human breast cancer MCF-7 cells proliferation was promoted after lowering the expression of human Wnt9a by RNAi, but inhibited after over-expression of human Wnt9a. All those suggest the expression level of human Wnt9a may play a role in adjusting the rate of cell proliferation ofhES and MCF-7 cells.
