Characterization of an insulin receptor-related receptor in Biomphalaria glabrata embryonic cells

Tyrosine kinase receptors play a key role in the communication of cells wit h their environment. Growth hormone receptors, such as insulin receptors, a re involved in the regulation of cell growth, differentiation and metabolis m in multicellular organisms. Insulin-related peptides and members of the i nsulin receptor subfamily have been described in a wide variety of inverteb rates, including freshwater molluscs. In this paper, we describe the metabo lic effect of insulin on a mollusc cell line (Bge) derived from embryos of the snail Biomphalaria glabrata. Using a PCR strategy, we have cloned from Bge cells a cDNA encoding a protein (BgIR) homologous to, and exhibiting al l of the typical features of insulin receptors. Northern blot analysis conf irmed the expression of BgIR in B. glabrata snails and suggested its wide d istribution in the snail body. Bge cells have been shown to provide the env ironmental conditions necessary for the in vitro development of the sporocy sts of Schistosoma mansoni, a trematode parasite that uses B. glabrata as a n intermediate host. The possible implication of BgIR in the activating and proliferating processes observed in Bge cells during their coculture with S. mansoni larvae is discussed. (C) 2001 Elsevier Science B.V. All rights r eserved.