Biology subjects

Naseer, S.

Publications and source records attributed to Naseer, S..

3 recordsLinked to original sources

bioRxiv2026

Haplotypes variations of yellow stripe like (TaYSL) genes are associated with grain iron and zinc contents in wheat (Triticum aestivum L.)

The availability of pangenome and resequencing of wheat collections have facilitated the discovery of gene-trait associations in wheat. Yellow stripe-like (YSL) proteins play a key role in the uptake and translocation of metals and yet have not been fully identified and analyzed at the genome-wide level in wheat. In this study, 26 TaYSL genes were identified and divided into four distinct clades, each clade sharing similar domains and motif compositions. Most genes were upregulated under iron deficiency, whereas homoeologs of TaYSL1 were downregulated. Both SNP-based and haplotype-based association studies were used to dissect the role of TaYSLs underpinning grain iron contents (GFeC) and zinc contents (GZnC) in wheat. TaYSL6-2B and TaYSL16-1A haplotypes showed strong association with GFeC, and TaYSL14-6A showed strong association with GZnC in multiple field trials. The distribution of favorable haplotypes in global wheat collection of [~]3000 accessions showed that majority of haplotypes were more prevalent in landraces and winter wheat compared to modern cultivars and spring types, indicating their potential for use in breeding. The combination of favorable haplotypes of three YSL genes associated with GFeC and GZnC were very rare, and most of the wheat accessions has single or double favorable haplotypes. These findings provide the first comprehensive characterization of the TaYSL gene family in wheat and identify significant SNPs and elite haplotypes that can be utilized for genetic improvement and biofortification.

plant biology↗

bioRxiv2025

Gene gain and loss drive the diversification of gig immune genes in teleosts: structural and regulatory insights from Atlantic salmon

Interferon-stimulated genes (ISGs) are key players in vertebrate antiviral immunity. Among teleost ISGs, the grass carp reovirus-induced gene (gig) families 1 and 2 (gig1 and gig2, respectively) are absent in mammals but conserved in fishes and amphibians, and they have been implicated in resistance to viral infections across several aquaculture species. In particular, gig1 and gig2 genes are transcriptionally induced by viral stimuli in teleosts such as zebrafish, grass carp, and salmonids, and recent studies have highlighted their potential involvement in resistance to economically important diseases like pancreas disease in Atlantic salmon. Yet, the rapid evolution of these genes hinders a comprehensive understanding of their diversification process and regulatory mechanisms. This study investigated gig gene evolution across teleosts, with a focus on Atlantic salmon (Salmo salar). Phylogenetic analysis across representative ray-finned fishes (Actinopterygii), including both teleosts and non-teleost outgroups such as the spotted gar (Holostei), indicated that gig1 is restricted to teleosts, with no identifiable homologs in non-teleost lineages. In contrast, gig2 genes are present in both teleosts and the spotted gar, suggesting an origin prior to the teleost-specific whole genome duplication (Ts3R), likely in early non-amniote vertebrates. Whole-genome duplication drove lineage-specific expansions, particularly of gig2 in salmonids. Structural and transcriptomic analyses showed that gig1 and gig2 differ in domain composition, repeat content, and regulation. Our findings suggest the complex interplay of duplication history, structural divergence, and transcriptional regulation in shaping immune gene repertoires in teleosts, with implications for understanding host-pathogen interactions and aquaculture disease responses. Article summaryThis study investigates the evolutionary history and diversification of the gig immune gene families in aquatic species, with particular focus on Atlantic salmon. Phylogenetic and structural analyses revealed that gig1 and gig2 follow distinct evolutionary trajectories, shaped by whole-genome and tandem duplications. Further analysis of Atlantic salmon gig genes showed divergent structures and regulation, highlighting a general role of gig genes in antiviral Interferon-mediated immunity and additionally suggesting functional specialization across gig paralogs. Together, these findings improve our understanding of immune gene evolution in fishes and provide insights relevant to antiviral defense and disease management in aquaculture species.

genomics↗

bioRxiv2022

Single cell transcriptomics of Atlantic salmon (Salmo salar L.) liver reveals cellular heterogeneity and immunological responses to challenge by Aeromonas salmonicida

The liver is a multitasking organ with essential functions for vertebrate health spanning metabolism and immunity. In contrast to mammals, our understanding of liver cellular heterogeneity and its role in regulating immunological status remains poorly defined in fishes. Addressing this knowledge gap, we generated a transcriptomic atlas of 47,432 nuclei isolated from the liver of Atlantic salmon (Salmo salar L.) contrasting control fish with those challenged with a pathogenic strain of Aeromonas salmonicida, a problematic bacterial pathogen in global aquaculture. We identified the major liver cell types and their sub-populations, revealing poor conservation of many hepatic cell marker genes utilized in mammals, while identifying novel heterogeneity within the hepatocyte, lymphoid, and myeloid lineages. This included polyploid hepatocytes, multiple T cell populations including {gamma}{delta} T cells, and candidate populations of monocytes/macrophages/dendritic cells. A dominant hepatocyte population radically remodeled its transcriptome following infection to activate the acute phase response and other defense functions, while repressing routine functions such as metabolism. These defense-specialized hepatocytes showed strong activation of genes controlling protein synthesis and secretion, presumably to support the release of acute phase proteins into circulation. The infection response further involved up-regulation of numerous genes in an immune-cell specific manner, reflecting functions in pathogen recognition and killing, antigen presentation, phagocytosis, regulation of inflammation, B cell differentiation and T cell activation. Overall, this study greatly enhances our understanding of the multifaceted role played by liver cells in immune defense and metabolic remodeling following infection and provides many novel cell-specific marker genes to empower future studies of this organ in fishes.

immunology↗