FUNCTIONAL ANALYSIS, SPATIAL AND TEMPORAL MRNA EXPRESSION OF THE KAZAL TYPE PROTEASE INHIBITOR FROM Sebastes schlegelii

Kazal-type serine protease inhibitor (KSPI) is one of the serpins, which plays a vital role to regulate and control the proteases as well as development for cellular component and defense. In this study, we have molecular characterized the KSPI cDNA sequence and discovered the spatial and temporal mRNA expression profile from Sebastes schlegelii (Ss). In silico study was conducted using various bioinformatics tools. The full-length of the Kazal-type protease inhibitor from Sebastes schlegelii (SsKSPI) was 532 bp, including open reading frame (ORF) of 330 bp. The ORF encoded a polypeptide of 110 amino acids with a signal peptide of 21 amino acids. Predicted molecular weight and the theoretical pI of SsKSPI were 12.33 kDa and 5.52 respectively. The greatest value of the Identity (42.9%) and similarity (50.9%) was observed with Channa striatas KSPI. Quantitative real time PCR (qRT-PCR) results showed that SsKSPI ubiquitously expressed in many tissues at different levels. Remarkably, SsKSPI transcripts in liver showed the highest expression (P < 0.05) followed by spleen and head kidney. The biotic and abiotic challenges were conducted and the liver tissue was assessed for the gene modulation by qRT-PCR. The mRNA expression of SsKSPI was significantly up-regulated throughout the challenge in response to S.iniae. The LPS challenge showed a gradual increment from 3h to 24h and going down at the late phase of the injection. The SsKSPI mRNA expression infected with Poly I:C has no significant point without 6h. Overall, the results showed that the SsKSPI is related to the immune system of black rockfish potentially.