Molecular characterization, computational analysis and transcript profiling of glutamate dehydrogenase (gdh) gene of Macrobrachium rosenbergii exposed to saline water

Glutamate dehydrogenase (GDH) plays a key role in the metabolism of free amino acids (FAA) in crustaceans and other metazoans. GDH has been widely implicated a central role in response to hyperosmotic condition. However, the response of GDH gene expression to salinity alterations has not yet been determined in Macrobrachium rosenbergii, a euryhaline prawn. To investigate the possible participatory role of GDH gene in altered salinity conditions, we have cloned and characterized GDH gene from M. rosenbergii (MrGDH) and examined the mRNA expression under salinity exposure. The full-length cDNA of MrGDH contained an open reading frame of 1659 nucleotides. The ELFV and NADP binding sites of GDH protein remained highly conserved with 99% identity within crustacean species. The sequence information of cDNA and gDNA together revealed that the MrGDH gene is encoded by an uninterrupted exon. We have generated the 3D structure of MrGDH protein. The significant expression level of GDH in various tissues of shrimp suggests a functional role of this gene during salinity exposure and adaptation. The results generated in this study validated the MrGDH as a potential biomarker for salinity adaptation and could be the first step towards elucidating mechanistic pathways resides during the salinity exposure and osmoregulation in M. rosenbergii.