Hst-1 transforming protein: expression in silkworm cells and characterization as a novel heparin-binding growth factor
Miyagawa, K.; Sakamoto, H.; Yoshida, T.; Yamashita, Y.; Mitsui, Y.; Furusawa, M.; Maeda, S.; Takaku, F.; Sugimura, T.; Terada, M.
Oncogene 3(4): 383-389
1988
ISSN/ISBN: 0950-9232 PMID: 2978866 Document Number: 318407
A protein encoded by an hst-1 transforming gene was expressed in silkworm-derived BmN cells and secreted into the culture medium using a recombinant baculovirus vector. The strong affinity for heparin of the secreted protein made it possible to purify the hst-1 protein to homogeneity in a two-step procedure. The purified hst-1 protein has a molecular weight of 18,000 and stimulates both DNA synthesis in NIH3T3 cells and human umbilical vein endothelial cell proliferation. In addition, morphological changes and anchorage-independent growth of NIH3T3 cells are induced by this product. These results show that the hst-1 transforming protein is a novel heparin-binding growth factor as predicted by nucleotide sequence analysis.