Molecular characterization of thioredoxin-like protein 1 (TXNL1) from big-belly seahorse Hippocampus abdominalis in response to immune stimulation. Issue 75 (April 2018)

• Record Type: Journal Article
• Authors: Liyanage, D.S.; Omeka, W.K.M.; Godahewa, G.I.; Lee, Jehee
• Is Part Of: Fish & shellfish immunology. Issue 75(2018)
• Page Start: 181
• Page End: 189
• Publication Date: 2018-04
• Subjects: Antioxidant protein -- Hippocampus abdominalis -- Immune challenge -- Redox balance -- Thioredoxin-like protein 1; Fishes -- Immunology -- Periodicals; Shellfish -- Immunology -- Periodicals; Poissons -- Immunologie -- Périodiques; Crustacés -- Immunologie -- Périodiques; 571.9617
• DOI: 10.1016/j.fsi.2018.02.009
• Languages: English
• ISSNs: 1050-4648

Abstract

Abstract: Thioredoxin is a highly conserved protein found in both prokaryotes and eukaryotes. Reactive oxygen species (ROS) are produced in response to metabolic processes, radiation, metal oxidation, and pathological infections. High levels of ROS lead to cell death via autophagy. However, thioredoxin acts as an active regulatory enzyme in response to excessive ROS. Here, we performed in-silico analysis, immune challenge experiments, and functional assays of seahorse thioredoxin-like protein 1 (ShTXNL1). Evolutionary identification showed that ShTXNL1 protein belongs to the thioredoxin superfamily comprising 289 amino acids. It possesses an N-terminal active thioredoxin domain and C-terminal proteasome-interacting thioredoxin domain (PITH) of ShTXNL1 which is a component of 26S proteasome and binds to the matrix or cell. Pairwise alignment results showed 99.0% identity and 99.7% similarity with the sequence of Hippocampus species. Conserved thiol-disulfide cysteine residue containing Cys-X-X-Cys motif may be found in the first few amino acids in the second beta sheet starting from the N-terminus. This motif can be discovered in ShTXNL1 as 14 CRPC 17 and comprised two N-linked glycosylation sites at 72 NISA 75 and 139 NESD 142 . According to the quantitative real-time polymerase chain reaction analysis from healthy seahorses, highest ShTXNL1 mRNA expression was observed in muscle, followed by ovary, brain, gill, and blood tissues. Moreover, significant temporal expression of ShTXNL1 was observed in gill and blood tissues after bacterial stimuli. Thus, the ShTXNL1 gene may be identified as an immunologically important gene in seahorse. Highlights: Big-belly seahorse thioredoxin-like protein 1 maintain redox homeostasis. TXNL1 is a component of 26S proteasome. Thiol active CXXC conserved motif consists in ShTXNL1. Spatial and temporal mRNA expression was evaluated. Radical scavenging ability, antioxidant activity, ferric-reducing activity measured.