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A D Mehta

Publications and source records attributed to A D Mehta.

22 records · Page 2Linked to original sources
PubMed1993

Genomic structure and sequence analysis of Drosophila melanogaster HSC70 genes.

We report the identification of two new members of the Drosophila melanogaster HSP70 gene family, HSC3 and HSC5. DNA sequence analysis predicts that HSC3 encodes a 72-kDa protein with a hydrophobic leader sequence and a C-terminal retrieval tetrapeptide, KDEL, characteristics associated with luminal endoplasmic reticulum (ER) proteins. Sequence analysis predicts that HSC5 encodes a 74-kDa protein with a characteristic mitochondrial leader sequence. We report the deduced amino acid (aa) sequence for the previously identified gene, HSC1. HSC1 encodes a 70-kDa protein lacking a leader sequence and is presumed to have a cytoplasmic localization. A comparison of the deduced aa sequences of these and hsc70 proteins from different species indicates that hsc70 proteins residing in the same intracellular compartment in different organisms are more similar to each other than are hsc70s from the same organism, but different organelles.

Amino Acid Sequence↗
PubMedDate not supplied

A spatiotemporal profile of visual system activation revealed by current source density analysis in the awake macaque.

We investigated the spatiotemporal activation pattern, produced by one visual stimulus, across cerebral cortical regions in awake monkeys. Laminar profiles of postsynaptic potentials and action potentials were indexed with current source density (CSD) and multiunit activity profiles respectively. Locally, we found contrasting activation profiles in dorsal and ventral stream areas. The former, like V1 and V2, exhibit a 'feedforward' profile, with excitation beginning at the depth of Lamina 4, followed by activation of the extragranular laminae. The latter often displayed a multilaminar/columnar profile, with initial responses distributed across the laminae and reflecting modulation rather than excitation; CSD components were accompanied by either no changes or by suppression of action potentials. System-wide, response latencies indicated a large dorsal/ventral stream latency advantage, which generalizes across a wide range of methods. This predicts a specific temporal ordering of dorsal and ventral stream components of visual analysis, as well as specific patterns of dorsal-ventral stream interaction. Our findings support a hierarchical model of cortical organization that combines serial and parallel elements. Critical in such a model is the recognition that processing within a location typically entails multiple temporal components or 'waves' of activity, driven by input conveyed over heterogeneous pathways from the retina.

Animals↗