Identification of a cDNA sequence coding for kruppel-like factor 2b (Klf2b) from the skin mucosa of common carp (Cyprinus carpio)

Kruppel-like factors (Klfs) are a highly related zinc-finger family of transcription factors implicated in the regulation of the eukaryotic cellular growth and differentiation of a diverse set of cells in mammal. Using RT-PCR technique, a 456 bp cDNA fragment encoding N-terminus part of a Klf2b was isolated from the skin mucosa of common carp (Cyprinus carpio) using two degenerative oligonucleotide primers. Use of this fragment as a probe allowed the isolation of a larger cDNA clone through the searching of the GenBank expressed sequence tag database. The size of the amplified product is 1157 bp, which encodes a polypeptide of 274 amino acid residues with a predicted molecular mass of 30.359 kDa and theoretical pI of 4.88. The deduced amino acid sequence exhibited 79, 54, and 53% identity to the homologous Klf2b identified from zebrafish Danio rerio, Spotted Green Pufferfish Tetraodon nigroviridis and Atlantic salmon Salmo salar, respectively. The common carp protein is 50% similar to Klf2 orthologues in African clawed frog Xenopus laevis, 44% in chicken Gallus gallus and is 30% similar to the mammalian Klf in house mouse Mus musculus.