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Pant, H. C.

Publications and source records attributed to Pant, H. C..

2 recordsLinked to original sources

CDK5 mediated phosphorylation of cytosolic phospholipase A2 regulates its activity and neuroinflammation in Parkinsons Disease

Hyperactivation of cyclin-dependent kinase 5 (CDK5) by p25, contributes to neuroinflammation causing neurodegeneration in Parkinsons Disease (PD) and Alzheimer diseases (AD). However, the mechanism by which CDK5 induces neuroinflammation in the PD brain is largely unexplored. Here, we show that CDK5 phosphorylates cytosolic phospholipase A2 (cPLA2) at Thr-268 and Ser-505 sites lead to its activation and generation of eicosanoid products. Mutational studies using site-directed mutagenesis and molecular simulations show that the architecture of the protein changes upon each single-point mutation. Interestingly, double-mutations also led to severe decline in the activity of cPLA2 and disruption of its translocation to the plasma membrane. Further, the brain lysates of transgenic PD mouse models show hyperactivation of CDK5 resulting in enhanced phosphorylation of Thr-268 and Ser-505 of cPLA2 and its heightened activity confirming the findings observed in the cell culture model of PD. These phosphorylation sites of cPLA2 and CDK5 could be explored as the future therapeutic targets against neuroinflammation in PD. Further, conjoint transcriptomic analysis of the publicly available human PD datasets strengthens the hypothesis that genes of the arachidonic acid, prostaglandin synthesis and inflammatory pathways are significantly upregulated in case of the PD patients as compared to that of healthy controls.

neuroscience↗

FMRF Gene Expression In The Nervous System Of The Squid Doryteuthis pealei* Hatchling

FMRFamide is a neuropeptide that is widely distributed in invertebrates and known to be involved in many physiological functions. Previously we noted marked differences in expression of the fmrf gene in the stellate ganglion of Doryteuthis pealei* compared to the central nervous system. In this study we aimed to examen the brain systems of Doryteuthis pealei* for the presence and distribution of fmrf-expressing cells and fiber networks. Late squid embryos and hatchlings were examined by in situ hybridization and immunohistochemistry in whole mounts and tissue sections. All central lobes contained limited numbers of scattered neurons expressing fmrf, but the FMRFamide-containing fiber systems were abundant and extensive, mostly present in the neuropil of lobes. Main clusters of neurons were located in the magnocellular and chromatophore lobes of the posterior subesophageal mass (PSM), and in dorsal aspects of the basal lobe (BL). Dense FMRFamide-immunoreactive fibers were particularly seen in the optic lobe (OL), medial and posterior supraesophageal masses (MSM and SPM) often with a commissural organization. The data show that the central lobes of Doryteuthis pealei hatchlings have a matured FMRFamide system organized in a limited number of centers, but with widely distributed efferents. This suggests that FMRFamide neurons are already functionally engaged in the late embryo. The localization indicates that control of chromatophores and fin movement are amongst these functions.

neuroscience↗