Characterization of type IV antifreeze gene in Nile tilapia (Oreochromis niloticus) and influence of cold and hot weather on its expression and some immune-related genes.

The aim of this work is to study the effect of the thermal stress of ambient temperature during winter and summer on the expression of type IV antifreeze gene (ANF IV) in different tissues of Nile tilapia (Oreochromis niloticus) as well as some immune-related genes. At first, genomic ANF IV gene was characterized from one fish; 124 amino acids were identified with 92.7% similarity with that on the gene bank.