Programmed cell death regulatory genes in primitive Euometazoa

The aim of this manuscript is to study for the first time identification, extraction and expression pattern of lifeguard genes in fresh water polyp Hydra Vulgaris. To do this objective, 100 freshwater polyps were cultured and total DNA extraction was performed. Specific primers were designed for all genes and PCR reaction applied to amplify Lifeguard genes. In order to investigate the gene expression pattern, In situ hybridization experiment used. The experiments revealed that there are three lifeguard genes in hydra, which are called Lifeguard-4 and two homologous of invertebrates’ Lifeguard-1. In situ hybridization showed that Lifeguard-4 expressed in endodermic layer of polyps in all budding stages and also in different stages of oogenesis. Phylogenetic analysis indicated that lifeguard genes are well conserved and present at the base of Euometazoa like freshwater Hydra polyp. Since apoptosis signaling pathway is present during Hydra gametogenesis (oogenesis and spermatogenesis), expressions of Lifeguard-4 as an apoptosis regulatory gene, in places were apoptosis occur is logistic and confirms the regulatory function of these genes.