ISOLATION OF HEART AND CARDIOGENIC PRIMORDIUM FROM EARLY JAPANESE-QUAIL EMBRYOS FOR RNA AND GENE-EXPRESSION STUDY

We have successfully and reproducibly isolated total RNA from small am ounts of Japanese quail cardiac tissue (sample size of 5-25 embryonic hearts), employing the Triozol method for RNA preparation. We have iso lated RNA from the embryonic heart of approximately 150 quail embryos, at different stages of myocardiogenesis, including 8-14 somite stages , 15-19 somite stages, and 20-34 somite stages. We have also isolated the cardiogenic primordium from 2-8 somite stages. In addition, we iso lated myocardial RNA from approximately 400 Japanese quail embryos of the hypodynamy-selected Ivanka 01 strain of Japanese quail (Institute of Animal Biochemistry and Genetics, Slovak Academy Sciences). Specifi cally, we obtained total RNA from embryonic hearts of approximately 10 0 Japanese quail embryos from each of these stages: 8-14 somites, 15-1 9 somites, and 20-34 somites. We have developed these isolation proced ures in support of our investigations of avian heart development. The aim of this work is to examine the effect of gravity (hypergravity and 1 g) on the expression pattern of specific groups of genes, in the em bryonic heart of developing chick and quail embryos. Based on these re sults we will, formulate a cellular and molecular biologic model of ho w the developing cardiac myocyte senses and responds to gravity and ch anged load application during its development.