Mouthbrooding behavior and sexual immune dimorphism in Indian perch <i>Jaydia lineata</i>

Abstract

<p>Parental care enhances offspring survival in teleost vertebrates; however, its genetic basis and evolutionary traits remain unexplored. Therefore, we assembled the chromosome-level genome of the paternal mouthbrooder, <i>Jaydia lineata</i>, and observed convergent evolution in parental care fish. Genomic signatures revealed the association of certain genes with embryonic development, implying that parental behavior is conducive for offspring. Adaptive convergence occurred as an in evolutionary response oxytocin signaling pathway-related genes; thus, hormonal regulation is vital in this process. Specific neuropeptides and steroid hormones co-opted and primary immunodeficiency-related transcripts were enriched in Indian perch. Comparative transcriptome analysis revealed a trade-off between parental care and immunological activation in mouthbrooders. Sexual immune dimorphism, evident in the buccal mucosa, is characterized by the functional differentiation of immune-related genes in male mouthbrooders. Thus, we elucidated the genetic basis and unique physiological traits of mouthbrooding, offering insights into the independent evolution of complex parental care adaptations in teleosts.</p>