Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.9.3.1 (cytochrome oxidase)
 8,822 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have identified an RNA species that appears to be induced by oxidative stress in hamster HA-1 fibroblasts using the differential display technique, but instead is found to be degraded when evaluated by Northern blot hybridization. Cloning and subsequent sequencing identified the partially degraded RNA as 16S ribosomal RNA (rRNA), a major component of mitochondrial ribosomes. Degradation, and associated decreases in the levels of the mature- and precursor-species of 16S rRNA, appear to be dependent upon calcium, but not cytoplasmic protein synthesis nor nuclear transcription. Other decreased mitochondrial RNAs were also identified, including 12S rRNA, NADH dehydrogenase subunit 6, ATPase subunit 6, and cytochrome oxidase subunits I and III. A significant part of many, if not all, of these RNA decreases was due to degradation. As compared with 16S rRNA, significantly less degradation was observed for cytoplasmic 28S/18S rRNAs, even at very high peroxide concentration. Analysis of 21 cytoplasmic mRNAs revealed little or no decrease in mature band signal in response to peroxide, and several cytoplasmic mRNAs were actually up-regulated. Thus, a preferential down-regulation of mitochondrial RNAs occurs in HA-1 fibroblasts in response to hydrogen peroxide. Subcellular fractionation analysis, using 16S rRNA degradation as a gauge, indicates that this down-regulation is specific to mitochondria. The down-regulation of mitochondrial RNAs may represent a general mechanism by which cells protect themselves against oxidative stress.
 ...
PMID:Down-regulation of mammalian mitochondrial RNAs during oxidative stress. 898 Oct 48

Chrysomyxa rusts are fungal pathogens widely present in the boreal forest. Taxonomic delimitation and precise species identification are difficult within this genus because several species display similar morphological features. We applied a DNA barcode system based on the ribosomal internal transcribed spacer region (ITS), large subunit (28S) ribosomal RNA gene, mitochondrial cytochrome oxidase 1 (CO1) and mitochondrial NADH dehydrogenase subunit 6 (NAD6) in 86 strains from 16 different Chrysomyxa species, including members of the Chrysomyxa ledi species complex. The nuclear ITS and 28S loci revealed higher resolving power than the mitochondrial genes. Amplification of the full CO1 barcode region failed due to the presence of introns limiting the dataset obtained with this barcode. In most cases the ITS barcodes were in agreement with taxonomic species based on phenotypic characters. Nevertheless we observed genetically distinct (different DNA barcodes) lineages within Chrysomyxa pyrolae and Chrysomyxa rhododendri, providing some evidence for allopatric speciation within these morphologically defined species. This finding, together with the observed pattern of host specificities of the studied rust fungi, suggest that species diversification within the C. ledi species complex might be governed by a set of factors such as specialisation to certain Ericaceae species as telial hosts and to a lesser extent specialization to different spruce species as aecial hosts. Moreover allopatric speciation by geographic disruption of species also seems to take place. When our data were integrated into a broader phylogenetic framework the Chrysomyxa genus unexpectedly was not resolved as a monophyletic group. Indeed the spruce cone rusts C. pyrolae and C. monesis coalesced with the pine needle rusts belonging to the genus Coleosporium, whereas the microcyclic species Chrysomyxa weirii was embedded within a clade comprising the genus Melampsora.
 ...
PMID:DNA barcoding in the rust genus Chrysomyxa and its implications for the phylogeny of the genus. 2165 58

Groupers of the family Epinephelidae are a diverse and economically valuable group of reef fishes. To investigate the evolution of their mitochondrial genomes we characterized and compared these genomes among 22 species, 17 newly sequenced. Among these fishes we identified three distinct genome organizations, two of them never previously reported in vertebrates. In 19 of these species, mitochondrial genomes followed the typical vertebrate canonical organization with 13 protein-coding genes, 22 tRNAs, two rRNAs, and a non-coding control region. Differing from this, members of genus Variola have an extra tRNA-Ile between tRNA-Val and 16S rRNA. Evidence suggests that this evolved from tRNA-Val via a duplication event due to slipped strand mispairing during replication. Additionally, Cephalopholisargus has an extra tRNA-Asp in the midst of the control region, likely resulting from long-range duplication of the canonical tRNA-Asp through illicit priming of mitochondrial replication by tRNAs. Along with their gene contents, we characterized the regulatory elements of these mitochondrial genomes' control regions, including putative termination-associated sequences and conserved sequence blocks. Looking at the mitochondrial genomic constituents, rRNA and tRNA are the most conserved, followed by protein-coding genes, and non-coding regions are the most divergent. Divergence rates vary among the protein-coding genes, and the three cytochrome oxidase subunits (COI, II, III) are the most conserved, while NADH dehydrogenase subunit 6 (ND6) and the ATP synthase subunit 8 (ATP8) are the most divergent. We then tested the phylogenetic utility of this new mt genome data using 12 protein-coding genes of 48 species from the suborder Percoidei. From this, we provide further support for the elevation of the subfamily Epinephelinae to family Epinephelidae, the resurrection of the genus Hyporthodus, and the combination of the monotypic genera Anyperodon and Cromileptes to genus Epinephelus, and Aethaloperca to genus Cephalopholis.
...
PMID:A comprehensive description and evolutionary analysis of 22 grouper (perciformes, epinephelidae) mitochondrial genomes with emphasis on two novel genome organizations. 2395 57