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Khan, W.

Publications and source records attributed to Khan, W..

2 recordsLinked to original sources

Comparative Transcriptomics of Mango (Mangifera indica L.) Cultivars Provide Insights of Biochemical Pathways Involved in Flavor and Color

Mango is an economically important fruit crop of many tropical and subtropical countries. Recently, leaf and fruit transcriptomes of mango cultivars grown in different geographical regions have characterized. Here, we presented comparative transcriptome analysis of four mango cultivars i.e. cv. Langra, cv. Zill, cv. Shelly and cv. Kent from Pakistan, China, Israel and Mexico respectively. De-novo sequence assembly generated 30,953-85,036 unigenes from RNASeq datasets of mango cultivars. KEGG pathway mapping of mango unigenes identified terpenoids, flavonoids and carotenoids biosynthetic pathways involved in flavor and color. The analysis revealed linalool as major monoterpenoid found in all cultivars studied whereas, monoterpene -terpineol was specifically found in cv. Shelly. Ditepene gibberellin biosynthesis pathway was found in all cultivars whereas, homoterpene synthase involved in biosynthesis of 4,8,12-trimethyltrideca-1,3,7,11-tetraene (TMTT; an insect induced diterpene) was found in cv. Kent. Among sesquiterpenes and triterpenes, biosynthetic pathway of Germacrene-D, an antibacterial and anti-insecticidal metabolite was found in cv. Zill and cv. Shelly. Two bioactive triterpenes, lupeol and {beta}-amyrin were found in cv. Langra and cv. Zill. Unigenes involved in biosynthesis of carotenoids, {beta}-carotene and lycopene, were found in cultivars studied. Many unigenes involved in flavonoid biosynthesis were also found. Comparative transcriptomics revealed naringenin (an anti-inflammatory and antioxidant metabolite) as central flavanone responsible for biosynthesis of an array of flavonoids. The present study provided insights on genetic resources responsible for flavor and color of mango fruit.

bioinformatics

The eIF2α Kinase Heme Regulated Inhibitor (HRI) Protects The Host From Infection By Regulating Intracellular Pathogen Trafficking

Phosphorylation of eIF2 by its kinases is a stress response universally conserved among the eukaryota. Previously, we reported that the eIF2 kinases Heme Regulator Inhibitor (HRI) and Protein Kinase R (PKR) control distinct activities of diverse bacterial pathogens. Specifically for Listeria monocytogenes, it was shown that in HRI-deficient cells there was a reduction in the translocation of the pathogen to the cytosolic compartment as well as reduced loading of pathogen-derived antigens on MHC-1 complexes. Here we show that Hri -/- mice, as well as wild-type mice treated with a HRI inhibitor, are more susceptible to listeriosis. In the first few hours of L. monocytogenes infection, Hri -/- mice supported greater pathogen proliferation in the liver compared to that observed in Hri +/+ mice. This greater susceptibility of Hri -/- mice was not due to deficits in immune cell development as proportions and numbers of innate and adaptive cell compartments were largely normal and these mice could mount potent antibody responses to a model T cell-dependent antigen. Using in vitro cellular infection assays, we show that the rate of pathogen efflux from infected Hri -/- macrophages and fibroblasts is significantly higher than that observed in infected Hri +/+ cells. In contrast to the stark differences between Hri +/+ and Hri -/- cells in the infection dynamics of virulent L. monocytogenes, HRI was entirely dispensable for killing non-virulent strains of L. monocytogenes. These results suggest that in wild-type cells, HRI helps ensure the cellular confinement of virulent L. monocytogenes and loading of cytosolic-derived antigens on MHC-1 complexes that limit pathogen spreading and activating innate immune responses, respectively.

immunology