Wnt1 promotes the proliferation of midgut epithelial cells in silkworm, Bombyx mori

Wnt genes are crucial members of at least three major signaling pathways that control diverse cellular behaviors, such as cell fate decisions, cell migration, and cell proliferation. Wnt genes are involved in many important embryological events, including the development of the gastrula, heart, limb, and nervous system. In this paper, we identified and characterized BmWnt1 in midgut of silkworm larvae, a lepidopteran model insect. The gene expression analysis revealed that BmWnt1 is expressed in most organs although in different patterns. In vivo, the addition of dextran sulfate sodium (DSS) promoted the proliferation of midgut epithelial cells with BmWnt1 up-regulation. In vitro, the down-regulation of BmWnt1 expression by RNA interference significantly inhibited cell proliferation. Taken together, we anticipate that BmWnt1 may contribute to cell proliferation and development in the silkworm midgut.