Cloning of cDNAs for the Precursor Protein of a Low-Molecular-Weight Subunit of the Inner Layer of the Egg Envelope (Chorion) of the Fish Oryzias latipes

AbstractcDNA clones for L-SF, the precursor of a low-molecular-weight subunit (ZI-3) of the inner layer of the Oryzias latipes egg envelope were isolated from Lambda ZAP cDNA libraries constructed from the poly(A)+ RNA of the liver of spawning female fish and estrogen-treated male fish. Among them, a clone, L-SF41, is 1473 bp long and contains an open reading frame encoding a signal peptide of 19 amino acids and L-SF protein of 420 amino acids. L-SF protein seems to be glycosylated, judging from the result of the glycanase digestion. L-SF protein contains a domain similar to ZP-domains in ZP3 of some mammalian species. Northern blot analysis employing XhoI-SmaI fragments of the cloned cDNA as probes revealed that expression of the L-SF gene occurred exclusively in the livers of spawning female fish and estrogen-treated male fish and that there was no mRNA encoding L-SF in the ovary of the spawning female fish

Effectiveness of Combined Treatment using X-rays and a Phosphoinositide 3-kinase Inhibitor, ZSTK474, on Proliferation of HeLa cells in vitro and in vivo

ZSTK474 is a novel orally applicable PI3K-specific inhibitor and strongly inhibits cancer cell proliferation. To explore further the antitumor effect of ZSTK474 for future clinical usage, combined effects with radiation were studied. The proliferation of HeLa cells was inhibited by the treatment with X-rays alone or ZSTK474 alone. The combination treatment with X-rays and ZSTK474 applied after 24 h post-irradiation for 8 days remarkably enhanced the cell growth inhibition. The combined effect was also observed for the clonogenic survival with continuous ZSTK474 treatment. Western blotting showed enhanced phosphorylation of Akt and GSK-3beta by X-irradiation, whereas the phosphorylation was inhibited by the ZSTK474 treatment alone. The treatment with ZSTK474 after X-irradiation also inhibited the phosphorylation. Combination of ZSTK474 and X-rays also remarkably inhibited xenograft tumor growth. The combined treatment with X-rays and ZSTK474 had a great therapeutic potential than the radiation or the drug therapy alone both in vitro and in vivo