Development and validation of microsatellite markers in a protandrous fish species Eleutheronema tetradactylum (Shaw, 1804) through cross-species amplification

The four fingered threadfin Eleutheronema tetradactylum (Shaw, 1804) is a prioritised species for mariculture in India. Their demand in the domestic markets is rapidly growing. Genetic stock structure analysis of fish populations is an important aspect from fisheries management perspective. The present study was conducted to develop microsatellite primers through cross-priming to elucidate the genetic structure of E. tetradactylum. A total of 13 polymorphic microsatellite markers were developed from the resource species, Pacific salmon Polydactylus sexfilis. The observed mean and the effective number of alleles were found to be 11.962 and 6.927 respectively. The mean of observed heterozygosity (Ho) and expected heterozygosity (He) values obtained were 0.784 and 0.798 respectively. These new microsatellite markers can be used as effective tools for studying genetic disparity as well as for elucidating evolutionary relationships among E. tetradactylum populations

Molecular identification of Bigeyes (Perciformes, Priacanthidae) from Indian waters

Thirty-five individuals of six priacanthid fish species were sampled from different localities along the coast of India covering the Arabian Sea and Bay of Bengal. The partial sequence of 16S rRNA and cytochrome oxidase subunit I (COI) genes were analyzed for species identification and phylogenetic relationship among the Indian priacanthids (Priacanthus hamrur, P. prolixus, P. blochii, P. sagittarius, Cookeolus japonicus, and Pristigenys refulgens). The intraspecies genetic distance ranged from 0.000 to 0.002, while distances varied from 0.008 to 0.157 interspecies based on 16S sequences. Using COI data analysis, the intraspecies genetic distance ranged from 0.000 to 0.005, while interspecies distances varied from 0.009 to 0.108. Several sequences labeled Priacanthus hamrur in GenBank are shown to be P. prolixus. We also observed cryptic speciation in Heteropriacanthus cruentatus. Partial sequences of 16S rRNA and COI genes provided phylogenetic information to distinguish thirteen species of priacanthids, indicating the usefulness of molecular markers in species identification

Identification of microsatellite loci, gene ontology and functional gene annotations in Indian salmon (Eleutheronema tetradactylum) through nextgeneration sequencing technology using illumina platform

Whole genome sequencing was performed on three samples of four finger threadfin Eleutheronema tetradactylum (KET25, KET29 and KET30) using illumina NextSeq500 platform using 2×150 bp chemistry. 8,390,317, 7,085,775 and 8,461,589 high quality reads were obtained after trimming low quality reads and adapter sequence. These high quality reads obtained were used for de novo assembly and obtained a number of scaffolds. From these scaffolds of vast sequenced data, we were able to identify 60246, 46107 and 60907 Simple Sequence Repeats (SSR) markers in KET25, KET29 and KET30 respectively, which will be useful in population genetic analysis and other diversity studies in Indian salmon. The gene prediction on assembled scaffolds predicted 31,943 genes for KET25; 26,487 genes for KET29 and 31,654 genes for KET30 with average gene size of 458bp, 424bp and 459bp respectively. A total of 30,209, 25,107 and 29,943 genes were annotated against the NCBI Nr database for the samples respectively. E. tetradactylum is a commercially important fish species for many countries. This is the first report on the identification of genomic SSR markers in E. tetradactylum using NGS technology. This study provides an insight of baseline knowledge of the genome sequence of Indian salmon for future studies

Human Mast Cells (HMC-1 5C6) Enhance Interleukin-6 Production by Quiescent and Lipopolysaccharide-Stimulated Human Coronary Artery Endothelial Cells

We examined the effect of intact human mast cells (HMC-1 5C6) and their selected mediators on interleukin-6 (IL-6) production and bone morphogenetic protein-2 (BMP-2) expression in human coronary artery endothelial cells (HCAEC) in the presence and absence of lipopolysaccharide (LPS). Scanning electron microscopy showed that HMC-1 5C6 cells adhere to HCAEC in cocultures. Addition of HMC-1 5C6 cells markedly enhanced the IL-6 production by quiescent and LPS-activated HCAEC even at the maximal concentration of LPS. Furthermore, mast cell-derived histamine and proteases accounted for the direct and synergistic effect of mast cells on IL-6 production that was completely blocked by the combination of histamine receptor-1 antagonist and protease inhibitors. Another novel finding is that histamine was able to induce BMP-2 expression in HCAEC. Collectively, our results suggest that endotoxin and mast cell products synergistically amplify vascular inflammation and that histamine participates in the early events of vascular calcification

Mitochondrial signatures for identification of grouper species from Indian waters

Groupers are important commercial fish in many parts of the world. Accurate identification is critical for effective conservation assessment and fisheries management. Genetic barcodes provide a simple and reproducible method for the identification of species even in the absence of taxonomic expertise. The generation of reference barcodes from properly identified specimens is an important first step in this direction. Here, 36 species belonging to the subfamily Epinephelinae (Family: Serranidae) were collected from landings on the west coast of India and Port Blair, Andaman, and partial nucleotide sequence data of the mitochondrial cytochrome C oxidase subunit I (COI) gene was generated. Barcodes for 13 species were developed from Indian waters for the first time. Analysis using the COI gene produced phylogenetic trees in concurrence with other multi-gene studies. Epinephelus fasciatus and E. areolatus were found to be a species complex, as hypothesized in other studies. The DNA barcodes developed in the study can be used for identifying species within Epinehelinae, where taxonomic ambiguity still exists

Population structure of Spanish mackerel Scomberomorus commerson (Lacepede 1800) in the Northern Indian Ocean determined using microatellite markers

Narrow barred Spanish mackerel, Scomberomorus commerson (Lacepede, 1800) is one of the economically important marine fish species in the Northern Indian Ocean. Genetic stock structuring is reported in S. commerson from Arabian Peninsula, Indo-West Pacific, Northern Australian, Southeast Asia and Northern Australia. The present study utilized microsatellite markers to elucidate the population structure of S. commerson (Lacepede, 1800) in the Arabian Sea and Bay of Bengal. A total of 12 polymorphic microsatellite loci were amplified in 250 samples collected from five different geographic locations. Low FST values (0.0023–0.027), AMOVA, PCoA and the Bayesian analysis of genetic structure indicated unit stock of the species in Indian waters. Bottleneck analysis using Wilcoxon signed rank tests and Mode shift test indicated lack of recent bottleneck events across populations of S. commerson. The findings of the present study could be used in managing the commercially important species, S. commerson as a unit stock in Arabian Sea and Bay of Bengal of Northern Indian Ocean and reinforces the need for regional cooperation on fisheries management

DNA barcoding and taxonomic notes on the genus Macolor (Perciformes: Lutjanidae) from Indian waters

The DNA “barcode”, the partial sequence of the mitochondrial gene cytochrome C oxidase subunit I (COI), was assessed for species identification within the genus Macolor. The Midnight Snapper, Macolor macularis Fowler 1931, is compared with its only congener, the Black and White Snapper, Macolor niger (Forsskål 1775), both collected from the south-west coast of India. The examination of fresh specimens of the two species showed diagnostic anatomical and coloration differences and the DNA barcoding showed a genetic divergence of 3.51% between the species. We provide a description and illustrations of DNA-barcoded specimens, assess the reliability of some key marking characters for the two species, and document the DNA barcodes for Indian specimen

Identification and characterisation of microsatellite markers in narrow barred Spanish mackerel Scomberomorous commerson (Lacepede, 1800)

Narrow barred Spanish mackerel, Scomberomorus commerson (Lacepede 1800) is one of the commercially important fish in Indian waters. For sustainable management of the species, it is necessary to understand the genetic stock structure of the species. Accurate delineation of genetic stock structure can be achieved using nuclear microsatellite markers. A study was carried out to identify and validate polymorphic microsatellite markers in S. commerson using information available from closely related fish species. The study could identify 10 polymorphic microsatellite loci which can be effectively utilised for identifying genetic stock structure of the species. Validation of the identified loci was also done by testing the loci in natural populations of the species. The findings of the present study will be useful in devising stock-specific management measures for conservation and sustainable utilisation of this commercially important fish species in Indian waters

Mast cell-mediated immune regulation in health and disease

Mast cells are important components of the immune system, and they perform pro-inflammatory as well as anti-inflammatory roles in the complex process of immune regulation in health and disease. Because of their strategic perivascular localization, sensitivity and adaptability to the microenvironment, and ability to release a variety of preformed and newly synthesized effector molecules, mast cells perform unique functions in almost all organs. Additionally, Mast cells express a wide range of surface and cytoplasmic receptors which enable them to respond to a variety of cytokines, chemicals, and pathogens. The mast cell’s role as a cellular interface between external and internal environments as well as between vasculature and tissues is critical for protection and repair. Mast cell interactions with different immune and nonimmune cells through secreted inflammatory mediators may also turn in favor of disease promoting agents. First and forefront, mast cells are well recognized for their multifaceted functions in allergic diseases. Reciprocal communication between mast cells and endothelial cells in the presence of bacterial toxins in chronic/sub-clinical infections induce persistent vascular inflammation. We have shown that mast cell proteases and histamine induce endothelial inflammatory responses that are synergistically amplified by bacterial toxins. Mast cells have been shown to exacerbate vascular changes in normal states as well as in chronic or subclinical infections, particularly among cigarette smokers. Furthermore, a potential role of mast cells in SARS-CoV-2-induced dysfunction of the capillary-alveolar interface adds to the growing understanding of mast cells in viral infections. The interaction between mast cells and microglial cells in the brain further highlights their significance in neuroinflammation. This review highlights the significant role of mast cells as the interface that acts as sensor and early responder through interactions with cells in systemic organs and the nervous system

Molecular identification of three deepsea fish species of the genus Chelidoperca (Perciformes: Serranidae) from Indian waters

The deepwater basslets of the genus Chelidoperca has eight nominal species and these are relatively small fishes caught in trawl nets operated at depths greater than 100 m. Mitochondrial cytochrome c oxidase subunit 1 (COI) and 16S rRNA gene sequence variation among three species under the genus Chelidoperca viz., C. investigatoris, C. occipitalis and C. maculicauda from Indian waters and their phylogenetic relationship with other representatives from same genus was studied. Fifteen individuals of Chelidoperca were sampled from different localities in the east and west coasts of India and further, four COI sequences from GenBank were used to reconstruct the phylogenetic relationship in the genus Chelidoperca. Based on COI sequence data analysis, the intraspecies genetic distance ranged from 0.000 to 0.005 while interspecies distance varied from 0.073 to 0.194. With respect to 16S rRNA sequences, the intraspecies genetic distance ranged from 0.000 to 0.002, while interspecies genetic distance varied from 0.062 to 0.118. The mean genetic difference observed between C. investigatoris and the other species used in this study was 11.53%. Results of the study revealed that the genus Chelidoperca is monophyletic