Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.30.1 (S1 nuclease)
 3,660 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Genes for cytochrome oxidase subunit I (oxiA), ATPase subunit 9, NADH dehydrogenase subunit 3 (ndhC) and cytochrome oxidase subunit II (oxiB) are located within a 7.2 kb (1 kb = 10(3) bases or base-pairs) segment of the Aspergillus nidulans mitochondrial genome. Northern hybridization shows that abundant RNA molecules of 4.0, 2.5 and 1.5 kb, each containing copies of two or more genes, are transcribed from this region. The 4.0 kb molecule, which contains copies of each of the four genes but lacks the three oxiA introns, is cleaved at a point just upstream from ndhC to give rise to the 2.5 kb RNA, which contains copies of oxiA and the ATPase subunit 9 gene, and the 1.5 kb RNA, which carries ndhC and oxiB. The ATPase subunit 9 gene, which has no identified function, is therefore transcribed into an abundant RNA. S1 nuclease analysis indicates that there are no additional introns in the amino-terminal region of oxiA and that the 4.0 and 2.5 kb transcripts of this gene have staggered 5' termini, the most upstream of which is adjacent to the 3' end of the histidinyl-tRNA gene. The results suggest that transcription of this genome proceeds via a very limited number of primary transcripts with mature RNAs produced by extensive processing events including tRNA excision. RNA synthesis and processing in A. nidulans mitochondria therefore resembles the events occurring in metazoa rather than yeast.
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PMID:Processing of mitochondrial RNA in Aspergillus nidulans. 253 Mar 53

Sequencing of an open reading frame associated with cytoplasmic male sterility (CMS) in Petunia has revealed a gene fusion (the Pcf gene) containing the 5'-flanking and amino-terminal transmembrane segment of the ATP synthase proteolipid gene (atp9), parts of the cytochrome oxidase subunit II (coxII) coding region, and the carboxyl terminus and 3'-flanking region of an unidentified reading frame (urfS). The coxII region has several small deletions and tandem repeats that remove all of the segments coding for the residues involved in copper binding, but may possibly maintain the cytochrome c binding site. Normal atp9 and coxII genes and their transcripts are also present in the sterile cytoplasm. S1 nuclease protection studies identify fused gene transcripts only in CMS lines, with an increase in transcript amount in anthers relative to leaves.
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PMID:A fused mitochondrial gene associated with cytoplasmic male sterility is developmentally regulated. 288 95

We have isolated and sequenced the cytochrome oxidase subunit II (COII) gene from pea mitochondria. The coding sequence (777 bp) shows over 90% homology to the COII genes from three monocotyledonous plants (rice, maize and wheat) and one dicotyledonous plant (Oenothera berteriana). Several codons are deleted, however, in the pea COII gene. Of interest is the deletion in pea of the last three codons, including the stop codon, found at the 3' end of the other four COII genes. Instead, a new stop codon has been created due to a single-base substitution at the 13th bp downstream from the position of the original stop codon. This pea gene does not contain an intron which is found in all three monocots. Two distinct 5' termini of the pea COII transcripts have been identified by S1 nuclease mapping, one at 285 bp (site I) and the other at 302 bp (site II) upstream from the ATG codon. They are located at two identical sites within nearly perfect direct repeats. Transcripts with the 5' end corresponding to site I occur five time more frequently than those with the 5' end corresponding to site II. Both transcripts have the same 3' terminus which has been mapped to be at 193 to 195 bp downstream from the stop codon.
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PMID:Pea cytochrome oxidase subunit II gene has no intron and generates two mRNA transcripts with different 5'-termini. 298 76