Mount Desert Island Biological Laboratory

About: Mount Desert Island Biological Laboratory is a nonprofit organization based out in Bar Harbor, Maine, United States. It is known for research contribution in the topics: Squalus acanthias & Spiny dogfish. The organization has 898 authors who have published 819 publications receiving 34283 citations.

Text mining and manual curation of chemical-gene-disease networks for the comparative toxicogenomics database (CTD).

Abstract: Background The Comparative Toxicogenomics Database (CTD) is a publicly available resource that promotes understanding about the etiology of environmental diseases. It provides manually curated chemical-gene/protein interactions and chemical- and gene-disease relationships from the peer-reviewed, published literature. The goals of the research reported here were to establish a baseline analysis of current CTD curation, develop a text-mining prototype from readily available open source components, and evaluate its potential value in augmenting curation efficiency and increasing data coverage.

Osmoregulation by Gills of Euryhaline Crabs: Molecular Analysis of Transporters1

Abstract: SYNOPSIS. The physiological mechanisms by which aquatic animals regulate the osmoconcentration of their body fluids remain unclear despite many excellent studies of tissue and cell function. This review summarizes the current status of an ongoing molecular biological approach to investigating transporters and transportrelated enzymes in ion-transporting gills of osmoregulating crustaceans. We have identified cDNAs coding for six candidate proteins in gills of the blue crab Callinectes sapidus and the green shore crab Carcinus maenas, including a Na 1 1 K 1 ATPase a-subunit, a V-type H 1 -ATPase B-subunit, a Na 1 /H 1 exchanger, a Na 1 / K 1 /2Cl 2 cotransporter, two isoforms of carbonic anhydrase, and arginine kinase. Although our account is far from complete, examination of mRNA abundance by quantitative reverse transcription/polymerase chain reaction (RT/PCR) has identified candidates that are preferentially expressed in gill epithelium, including the Na 1 1 K 1 -ATPase a-subunit and Na 1 /H 1 exchanger. The osmoregulatory response to salinity reduction includes enhanced mRNA expression of at least one form of carbonic anhydrase.

Na(+)+K(+)-ATPase in gills of the blue crab Callinectes sapidus: cDNA sequencing and salinity-related expression of alpha-subunit mRNA and protein.

Abstract: Many studies have shown that hyperosmoregulation in euryhaline crabs is accompanied by enhanced Na(+)+K(+)-ATPase activity in the posterior gills, but it remains unclear whether the response is due to regulation of pre-existing enzyme or to increased gene transcription and mRNA translation. To address this question, the complete open reading frame and 3' and 5' untranslated regions of the mRNA coding for the alpha-subunit of Na(+)+K(+)-ATPase from the blue crab Callinectes sapidus were amplified by reverse transcriptase/polymerase chain reaction (RT-PCR) and sequenced. The resulting 3828-nucleotide cDNA encodes a putative 1039-amino-acid protein with a predicted molecular mass of 115.6 kDa. Hydrophobicity analysis of the amino acid sequence indicated eight membrane-spanning regions, in agreement with previously suggested topologies. The alpha-subunit amino acid sequence is highly conserved among species, with the blue crab sequence showing 81-83 % identity to those of other arthropods and 74-77 % identity to those of vertebrate species. Quantitative RT-PCR analysis showed high levels of alpha-subunit mRNA in posterior gills 6-8 compared with anterior gills 3-5. Western blots of gill plasma membranes revealed a single Na(+)+K(+)-ATPase alpha-subunit protein band of the expected size. The posterior gills contained a much higher level of alpha-subunit protein than the anterior gills, in agreement with previous measurements of enzyme activity. Immunocytochemical analysis showed that the Na(+)+K(+)-ATPase alpha-subunit protein detected by alpha5 antibody is localized to the basolateral membrane region of gill epithelial cells. Transfer of blue crabs from 35 to 5 per thousand salinity was not accompanied by notable differences in the relative proportions of alpha-subunit mRNA and protein in the posterior gills, suggesting that the enhanced Na(+)+K(+)-ATPase enzyme activity that accompanies the hyperosmoregulatory response may result from post-translational regulatory processes.