Catalog Number:

GT15077

Product Type:

Affinity purified

Immunogen Sequence:

NS0-derived rmSema 3C

Host:

Goat

Reactivity:

Mouse

Applications:

Western Blotting, ELISA

Description:

Semaphorins, or collapsins, constitute a family characterized by the presence of a conserved semaphorin domain at the N terminus. To identify proteins responsible for non-multidrug resistance (MDR) resistance to the chemotherapeutic agent cisplatin (CDDP), Yamada et al. (1997) introduced a CDDP-resistant human ovarian cancer cell cDNA expression library into CDDP-sensitive cells and selected for CDDP-resistance. They isolated a cDNA encoding a predicted protein that has 93% amino acid homology to mouse semaphorin E. The 616-amino acid human semaphorin E contains an N-terminal signal sequence of 15 amino acids that is followed by a semaphorin domain. In vitro translation of the semaphorin E cDNA yielded a 70-kD protein. The authors showed that semaphorin E is secreted by mammalian cells. CDDP-sensitive cells transfected with the semaphorin E cDNA acquired CDDP-resistance. Yamada et al. (1997) found that semaphorin E was overexpressed in CDDP-resistant cell lines and was induced by diverse chemotherapeutic drugs and by X-ray and UV irradiation. Aberrant semaphorin E protein expression was detected immunohistochemically in 33% of recurrent squamous cell carcinomas removed from patients who had received extensive radiochemotherapy. By Northern blot analysis, semaphorin E was expressed as a 5.2-kb transcript in all human tissues tested.

Reference:

1. Mangasser-Stephan, K.; Dooley, S.; Welter, C.; Mutschler, W.; Hanselmann, R. G. Identification of human semaphorin E gene expression in rheumatoid synovial cells by mRNA differential display. Biochem. Biophys. Res. Commun. 234: 153-156, 1997.

2. Yamada, T.; Endo, R.; Gotoh, M.; Hirohashi, S. : Identification of semaphorin E as a non-MDR drug resistance gene of human cancers. Proc. Nat. Acad. Sci. 94: 14713-14718, 1997.