Distribution analysis of profilin isoforms at transcript resolution with mRNA-seq and secondary structure in various organs of Rattus norvegicus.

Profilin (Pfn) is an actin binding protein, ubiquitously found in mammals and is essential for the actin polymerization in cells. In brain, it plays a pivotal role in neurogenesis and synapse formation by interacting with various proteins. Four Pfn isoforms have been identified in mammals. This study presents the identification and transcriptional expression of various Pfn isoforms (Pfn1, Pfn2, Pfn3 and Pfn4) in brain, heart, kidney, liver, and muscle and testis of Rattus norvegicus. Organs have been classified into groups based on some similarities. Group I includes brain and testis, Group II includes skeletal muscle and heart, while Group III includes kidney and liver. Pfn1 has been identified in all groups, Pfn2 and Pfn3 have been identified in group I, group III and in one organ (skeletal muscle) of group II. To the best of the authors knowledge, no report of Pfn1 and Pfn2 presence in testis, Pfn3 in brain, liver and skeletal muscle, Pfn4 in kidney and skeletal muscle exists to date. Transcriptional expression showed variations among expression level of different Pfn isoforms in various organs with respect to the control gene GADPH. We hypothesize that this could be attributed to profilin isoform specific mRNA structure and corresponding motifs, which generally contribute to similar or varied decay rates, cellular localization, post transcriptional regulation pattern and ligand binding.