Three SINE Insertion Polymorphic Sites were Identified in Insulin-like Growth Factor 2 mRNA-binding Proteins

Abstract

Background: The insulin-like growth factor-2 mRNA-binding proteins 1, 2 and 3 (IGF2BP1, IGF2BP2, IGF2BP3) belong to a conserved family of RNA-binding, oncofetal proteins, these RNA-binding proteins (RBPs) modulate important aspects of cell function during development and in cancer. However, the structural variations of IGF2BPs gene generated by retrotransposon insertion have not yet been reported. Methods: In this study, the bioinformatic prediction was performed to screen for retrotransposon insertion polymorphisms (RIPs) in IGF2BP genes.Sixteen predicted RIPs in IGF2BP genes were identified and three RIPs caused by the youngest SINEA1 retrotransposons and located in IGF2BP3 introns were verified by PCR. Result: Polymorphisms of these three RIPs in commercial breeds are poor, but in Chinese native pig breeds, all three RIPs showed abundant polymorphisms. This is consistent with the intensive selection of commercial pigs. In summary, our data suggested that there are at least three RIPs caused by SINE retrotransposons in the IGF2BP3 gene. And they shows different polymorphic distribution in Chinese native and commercial breeds, suggesting that they can be used for population genetic analysis.