Characterization and expression analysis of a thioredoxin-like protein gene in the sea cucumber Apostichopus japonicus. (November 2016)

• Record Type: Journal Article
• Authors: Cheng, Shixiong; Li, Chenghua; Wang, Yi; Yang, Limeng; Chang, Yaqing
• Is Part Of: Fish & shellfish immunology. Volume 58(2016:Nov.)
• Page Start: 165
• Page End: 173
• Publication Date: 2016-11
• Subjects: Thioredoxin -- Apostichopus japonicus -- Spatial expression -- Temporal expression -- Vibrio splendidus -- Recombinant protein; Fishes -- Immunology -- Periodicals; Shellfish -- Immunology -- Periodicals; Poissons -- Immunologie -- Périodiques; Crustacés -- Immunologie -- Périodiques; 571.9617
• DOI: 10.1016/j.fsi.2016.08.061
• Languages: English
• ISSNs: 1050-4648

Abstract

Abstract: As the most important disulfide bond reducates of intracellular oxidordeuctase, thioredoxin (TRX) plays a crucial role in maintaining reducing state of intracellular proteins to normally perform their function. In this study, a cDNA of TRX-like protein gene from Apostichopus japonicus (denoted as AjTRX ) was cloned and characterized. The full-length cDNA of AjTRX was of 1870 bp, consisting of a 5′-UTR of 101 bp, a long 3′-UTR of 887 bp and a 882 bp open reading frame (ORF) encoding a 293 amino acids. The predicted molecular mass and the theoretical PI of the deduced amino acids of AjTRX were 32.3 kDa and 5.52, respectively. Phylogenetic trees showed that AjTRX had a closer evolution relationship with TRX from Strongylocentrotus purpuratus . AjTRX was found to be ubiquitously expressed in all examined tissues including longitudinal muscle, coelomocytes, tube feet, intestine, respiratory tree and body wall indicating a general role in physiological processes. Temporal expression pattern of AjTRX in coelomocytes showed that AjTRX reached two peak expression levels at 8 h and 48 h after Vibrio splendidus challenge with a 8.6 and 9.3-fold increase compared to their control groups, respectively. The recombinant AjTRX protein (r AjTRX ) displayed obvious antioxidant activity in a dose-dependent manner, and the higher reducing activity was detected in 20 μM experimental group. All these results strongly suggested that AjTRX could play an important role as an antioxidant in a physiological context, and might be involved in the process of bacterial challenge. Highlights: The full-length cDNA of thioredoxin-like protein gene was cloned from Apostichopus japonicus by RACE technique. AjTRX was constitutively expressed in all tested tissues. AjTRX could be heightened after Vibrio splendidus challenge in coelomocytes. The recombinant AjTRX protein exhibited a high reducing activity in insulin disulfide reduction assay.