Detection of a Perilipin‐5 Splice Variant

Abstract

Alternative splicing occurs throughout the human genome, leading to multiple proteins from a single gene. The resulting proteins can be nearly identical or vastly different in how they function. The perilipins are a family of lipid droplet associated proteins that among other functions regulate interaction of lipases with their substrates. Alternative splicing within the perilipin family has been observed in perilipins 1 and 3, giving rise to proteins with varying functions. In the course of our studies on perilipin 5, an immunoblot signal was observed that corresponded to an approximately 35 kDa protein. Based on this data we hypothesized that perilipin 5 also undergoes alternative splicing. Western blot analysis of this shortened form of perilipin 5 has revealed its expression in C2C12 cultured myoblasts and in heart and liver mouse tissue. Further analysis of perilipin 5 cDNA through reverse transcriptase PCR provided evidence that this protein is a result of alternative splicing. Based on the current naming convention for the perilipin proteins, we have termed this protein perilipin 5b. The objective of the current study is to develop DNA based probes for use in northern blot analysis of perilipin 5. The genomic DNA sequence of perilipin 5 was analyzed to identify areas where splicing events could occur, and probes were designed accordingly to detect the different variants of perilipin 5. In the analysis of different mouse tissue samples, these probes have been used to detect which of the perilipin 5 splice variants are being expressed under different feeding conditions. Ongoing studies are seeking to determine the function of perilipin 5b.