Temporal Expression Pattern of Peptides in the Regenerating Caudal Fin of Teleost Fish Poecilia latipinna With Special Emphasis on krt15 and myl-1

Abstract

Amongst several vertebrates, caudal fin of teleost fish has been emerged as an excellent model to understand the mechanism of regeneration. By now it is well perceived that proper coordination of different regulatory signals are needed to facilitate the progression of successive stages of regeneration. Therefore, in the current study protein expression profile for caudal fin regeneration in Poecilia latipnna was brought into the focus. The pattern of protein turnover and variation in the expression level were observed across the stages of regeneration. Data from twodimensional gel electrophoresis revealed the differential expression of proteins for wound epithelium, blastema and differentiation stages when compared to resting stage. Based on the computational analysis, of the peptide expression profile and subsequent sequencing, two peptides namely Keratin type I cytoskeletal 15 and Myosin light chain-1 were studied further at transcript level. keratin-15 was found to be up regulated at wound epithelium stage while its expression waned significantly in the blastema and differentiation stages of regeneration indicating its role in the formation of a functional wound epithelium. Western blot analysis of keratin-15 also concurred with transcript levels of krt15. However, myl-1 transcript levels was observed to be dispensable for initial phase of regeneration whereas its elevated level in differentiation stage at both mRNA and protein level marks its noteworthy role in achieving the structural integrity of a regenerating caudal fin. This is the first observation of the involvement of keratin-15 and Myosin light chain-1 in the regulation of regenerative process in Poecilia latipinna.