Journal of the Marine Biological Association of India

De novo transcriptomic discovery and molecular characterisation of a caspase kinase gene in the elasmobranch, Chiloscyllium griseum

Volume 67 Issue 2

Pooja Harshan and Sandhya Sukumaran

doi:10.6024/jmbai.2025.67.2.2598-01

Abstract

Caspase kinases are the fundamental players of the apoptotic and immune signalling pathways in vertebrates. However, the molecular characterisation of this gene remains poorly delineated in elasmobranchs. The present study displays the first transcriptome-based approach in elucidating the molecular profile of the caspase kinase gene in Chiloscyllium griseum, a benthic shark inhabiting coral reefs and estuaries. The protocol follows the extraction of total RNA from immune-rich tissues such as the heart and liver with the aid of high-throughput sequencing technology. Functional annotation revealed a candidate caspase kinase transcript with an embedded serine/threonine kinase and caspase recruitment domains. The ORF prediction using TransDecoder encoded a 299 bp length amino acid that showed high homology with the caspase kinase from the vertebrate counterparts, suggesting evolutionary conservation. Gene expression profiling showed a significant level in the heart tissue rather than the liver (P<0.001), indicating its role in Cardiovascular apoptotic regulation. The dataset generated out of this investigation provides foundational molecular insights into apoptotic gene regulation in elasmobranchs, opening up new avenues in studies related to immune-apoptotic pathways in basal vertebrates.

Keywords

Chiloscyllium griseum, caspase kinase, transcriptome, apoptosis, immune genes, elasmobranch

Date : 04-12-2025