Acceleration of early chick embryo morphogenesis by insulin is associated with altered expression of embryonic genes

Abstract

In the present study, we show that insulin accelerates early morphogenesis in gastrulating chick embryo explants cultured in vitro, whereas antiserum to insulin adversely affects this process. Comparison between length of body axis of control and treated embryos clearly brings out the significant acceleration of development by excess insulin (0.175 to 17.5 nM). In embryos treated with 87.5 and 175 nM insulin, a high occurrence of abnormalities is observed. Treatment of embryos with antiserum to porcine insulin results in a high percentage of abnormalities, particularly in the forming neural tube. In situ hybridization of whole embryos using digoxigenin-labeled riboprobes showed that insulin modifies the expression of crucial developmental genes within 2 hours. While Brachyury, a pan-mesodermal marker gene, ERNI, the earliest known marker for neural induction in chick, and noggin, important in neural tube patterning, are upregulated, expression of goosecoid, necessary for gastrulation movements, does not appear to be significantly altered. During the same time, insulin does not exert any mitogenic effect on chick embryonic cells as assessed by nuclear counts. These findings demonstrate that insulin plays an important role in the early morphogenesis of the chick embryo. The function of insulin appears to be mediated by specific genes which orchestrate pattern formation during early development.

Proinsulin in development: new roles for an ancient prohormone

“…5) [51]. In parallel to this major role in survival/death control, insulin and proinsulin may also play a role in early morphogenesis and cardiogenesis [69,73,74]. Moreover, human fetuses lacking insulin receptor are significantly growth-retarded, showing a stronger phenotype than the insulin receptor knockout mouse (reviewed in [75]).…”

Effect of in ovo ghrelin administration on subsequent serum insulin and glucose levels in newly-hatched chicks

“…Glucose was found to readily enter the cells of the heart of 5-6 day chicken embryo, in which the uptake of 2-deoxyglucose was stimulated by physiological levels of insulin as early as 5-6 days (Kutchai et al, 1977). It has been shown that insulin has a considerable role in chicken early-embryonic morphogenesis with expression changes in the involved genes (Patwardhan et al, 2004).…”

Expression pattern of iodotyrosine dehalogenase 1 (DEHAL1) during chick ontogeny

“…A range of signaling molecules and their roles have been implicated in vertebrate development (Borgave and Ghaskadbi, 2009; SanchezCalderon et al, 2007;Patwardhan et al, 2004;Waschek et al, 1998;Hallbook et al, 1995;Ernfors et al, 1995;Hyuga et al, 1993). Thyroid hormones are known to play an important role in the early development including neurulation of several vertebrates and previous studies have shown the occurrence of enzymes that are involved in the recycling of Iodine from thyroid hormones (Courtin et al, 2005;Gereben et al, 2004;Geyten et al, 2002;Asteria, 1998;Becker et al, 1997;Rosenkilde and Ussing, 1996).…”