Identification, Characterization, and Tissue Expression Pattern of Alternatively Spliced Transcript Variants of Mouse RARRES2 Gene

Chemerin is a chemoattractant protein with adipokine and antimicrobial properties encoded by the retinoic acid receptor responder 2 ( RARRES2 ) gene. Chemerin bioactivity is largely dependent on carboxyl-terminal proteolytic processing that generates chemerin isoforms with the different chemotactive, regulatory and antimicrobial potential.While these mechanisms are relatively well known, a role of alternative splicing in generating isoform diversity remains obscure. Using rapid amplification of cDNA ends (RACE) PCR, we have identified novel transcript variant 4 of mouse RARRES2 encoding mChem153K. Moreover, RT-QPCR results and analysis of publicly available RNA-seq datasets showed that different alternatively spliced variants of mouse RARRES2 are present in mouse tissues, and their expression pattern was not affected by inflammatory nor infectious stimuli. Finally, we demonstratedthat chemerin isoform mChem157S exhibits higher bactericidal but not chemotactic activity compared to mChem156S. Together, our findings highlight the importance of an alternative splicing in generation of chemerin isoforms diversity and activity.