Publications by authors named "Venu M Margam"

The legume pod borer, Maruca vitrata (Lepidoptera: Crambidae), is an insect pest species of crops grown by subsistence farmers in tropical regions of Africa. We present the de novo assembly of 3729 contigs from 454- and Sanger-derived sequencing reads for midgut, salivary, and whole adult tissues of this non-model species. Functional annotation predicted that 1320 M.

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The body louse, with its recently sequenced genome, is now primed to serve as a powerful model organism for addressing fundamental questions relating to how insects interact with their environment. One characteristic of the body louse that facilitates this research is the size of its genome-the smallest insect genome sequenced to date. This diminutive genome must nonetheless control an organism that senses and responds to its environment, reacting to threats of corporal and genomic integrity.

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Background: Methamphetamine (METH), an abused illicit drug, disrupts many cellular processes, including energy metabolism, spermatogenesis, and maintenance of oxidative status. However, many components of the molecular underpinnings of METH toxicity have yet to be established. Network analyses of integrated proteomic, transcriptomic and metabolomic data are particularly well suited for identifying cellular responses to toxins, such as METH, which might otherwise be obscured by the numerous and dynamic changes that are induced.

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We report the assembly of the 14,054 bp near complete sequencing of the mitochondrial genome of the legume pod borer (LPB), Maruca vitrata (Lepidoptera: Crambidae), which we subsequently used to estimate divergence and relationships within the lepidopteran lineage. The arrangement and orientation of the 13 protein-coding, 2 rRNA, and 19 tRNA genes sequenced was typical of insect mitochondrial DNA sequences described to date. The sequence contained a high A+T content of 80.

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The completion of the rice genome sequence has made it possible to identify and characterize new genes and to perform comparative genomics studies across taxa. The aldehyde dehydrogenase (ALDH) gene superfamily encoding for NAD(P)(+)-dependent enzymes is found in all major plant and animal taxa. However, the characterization of plant ALDHs has lagged behind their animal- and prokaryotic-ALDH homologs.

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As an obligatory parasite of humans, the body louse (Pediculus humanus humanus) is an important vector for human diseases, including epidemic typhus, relapsing fever, and trench fever. Here, we present genome sequences of the body louse and its primary bacterial endosymbiont Candidatus Riesia pediculicola. The body louse has the smallest known insect genome, spanning 108 Mb.

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Maruca vitrata Fabricius is a pantropical lepidopteran pest of legumes. Phylogenetic analysis of a mitochondrial cytochrome c oxidase-I gene (cox1) fragment indicates that three Maruca sp. mitochondrial lineages have unique geographic distributions [lineages 1 and 2: Australia, Taiwan, and West Africa (Niger, Nigeria, and Burkina Faso), and lineage 3: Puerto Rico].

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Genomic DNA extraction protocols generally require the use of expensive and hazardous reagents necessary for decontamination of phenolic compounds from the extracts. In addition, they are lengthy, hindering large-scale sample extractions necessary for high-throughput analyses. Here we describe a simple, time and cost-efficient method for genomic DNA extraction from insects.

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Ecdysteroid titers and expression profiles of ecdysone-regulated genes were determined during the last instar larval and during the pupal stages of Aedes aegypti (Diptera: Culicidae). Three peaks of ecdysteroids occurring at approximately 24, 30-33 and 45-48h after ecdysis to the fourth instar larval stage were detected. In the pupa, a large peak of ecdysteroids occurred between 6 and 12h after ecdysis to the pupal stage.

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