CmZNF384-like gene in hypoxia-tolerant Indian catfish, Clarias magur (Hamilton 1822) in hypometabolic states associated with acute hypoxia and summer aestivation

In the present study, a novel gene designated as CmZNF384L, of which partial transcript (GenBank accession number JK487591) was identified previously to encode a zinc finger 384-like protein in suppression subtractive hybridization studies, was examined for its genetic feature and gene expression under normoxic and hypoxic conditions in Clarias magur. The largest ORF of assembled contig contains 1365 nucleotide residues and encodes a protein of 454 amino acids with eight Kru¨ppel-type zinc finger C2H2 domains, which is considered as a member of beta-beta-alpha zinc finger superfamily. Bioinformatic analysis of protein-protein interactions by STRING 10.0 yielded the highest score or confidence on its interaction with COL1A1. Gene expression analyses revealed constitutive transcript expression under normoxia in the six tissues examined, while the transcript levels were significantly higher, after both short-term (experimental) and long-term (natural) hypoxia in head kidney and heart tissues, after short-term hypoxia in spleen, and after long-term hypoxia in liver. No significant difference of transcript levels was observed in muscle and brain tissues between normoxic and hypoxic conditions. The pattern, especially increased transcript level in heart to hypoxia, may indicate critical role of CmZNF384L in the molecular mechanism of highly complex hypoxia tolerance in the species.