Molecular characterization, gene expression and dependence on thyroid hormones of two type I keratin genes (sseKer1 and sseKer2) in the flatfish Senegalese sole (Solea senegalensisKaup)

Abstract

Background: Keratins make up the largest subgroup of intermediate filaments, and, in chordates, represent the most abundant proteins in epithelial cells. They have been associated with a wide range of functions in the cell, but little information is still available about their expression profile and regulation during flatfish metamorphosis. Senegalese sole (Solea senegalensis) is a commercially important flatfish in which no keratin gene has been described yet.

Metamorphosis in Teleosts

“…The processes of skin stratification have been studied in greatest detail in zebrafish, but appear at least structurally similar in cichlids (Sire & Géraudie, 1983). Keratins mediate some of the skin restructuring events, and in flatfish, keratin expression is regulated directly by TH (Infante et al, 2007), decreasing after metamorphic climax (Campinho, Silva, Sweeney, & Power, 2007). The metamorphic transformation of flatfish skin resembles the metamorphic restructuring seen in amphibians (Power et al, 2008), in which keratin loci are also under TH control (Page et al, 2007).…”

Molecular characterization, gene expression and transcriptional regulation of cytosolic HSP90 genes in the flatfish Senegalese sole (Solea senegalensis Kaup)

“…This highly complex process, which involves drastic morphological and physiological changes in order to become an asymmetric benthic juvenile, is regulated by thyroid hormones (THs) (Manchado et al, 2008). During metamorphosis, several genes involved in central metabolic pathways and cytoskeleton such as the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (Manchado et al, 2007a), keratins (Infante et al, 2007), elongation factor 1 alpha (Infante et al, 2008a), and ribosomal proteins (Manchado et al, 2007b) modify their expression levels. Previous results on the ontogeny of HSP90 in silver sea bream indicated that HSP90 protein levels increased progressively from 1 DAH onwards, resembling the profile of cortisol and not that of THs (Deane and Woo, 2003).…”

Proteomic analysis through larval development of Solea senegalensis flatfish

“…Type II keratin, sseKer3 , is highly expressed just before metamorphosis onset and decreases during late metamorphosis . Type I keratin genes, sseKer1 and sseKer2 , also decrease during late metamorphosis . We have identified a truncated type II keratin with a maximum during early ontogenesis and a decrease to a minimum at the end of metamorphosis.…”

“…We have identified a truncated type II keratin with a maximum during early ontogenesis and a decrease to a minimum at the end of metamorphosis. In fish, deficient keratinization and the presence of dermal scales and mucus in adult skin is a common phenomenon and an adaptation to the aquatic environment . Type I and II sole keratins are down‐regulated by THs during metamorphosis, suggesting a role in tissue remodeling .…”

“…New genomic and bioinformatics resources have allowed the integrated analysis of transcript expression during larval development in different marine fish species . In the past, many genes that play key roles during larval development have been intensively studied in the Senegalese sole . However, most of the methods so far used focus on mRNA expression and do not fully reflect protein expression pattern due to post translational modification of proteins .…”