Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.30.2 (endonuclease)
 18,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A precursor of 5S ribosomal RNA from Bacillus subtilis (p5A rRNA, 179 nucleotides in length) is cleaved by RNase M5, a specific maturation endonuclease which releases the mature 5S rRNA (m5, 116 nucleotides) and precursor fragments derived from the 5' (21 nucleotides) and 3' (42 nucleotides) termini of p5A rRNA. Previous results (Meyhack, B., et al. (1978) Proc. Natl. Acad. Sci. U.S.A. 75, 3045) led to the conclusion that recognition elements in potential RNase M5 substrates mainly reside in the mature moiety of the precursor. Limited digestion of p5A rRNA with RNase T1 permitted the isolation of a number of test substrates which contained both precursor-specific segments and were unaltered in the immediate vicinity of the cleavage sites, but which differed in that more or less extensive regions of the mature moiety of the p5A rRNA were deleted. Tests of the capacity of these partial molecules to serve as substrates for RNase M5 indicate clearly that the enzyme recognizes the overall conformation of potential substrates, neglecting only the double-helical "prokaryotic loop" (Fox, G.E., & Woese, C.R. (1975) Nature (London) 256, 505).
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PMID:Involvement of the mature domain in the in vitro maturation of Bacillus subtilis precursor 5S ribosomal RNA. 10 77

Multiple drug resistance plasmid NR1 is shown to code for at least 10 low molecular weight RNAs. These species, ranging in size from 60 to 120 nucleotides, have been purified from minicells by two-dimensional gel electrophoresis and characterized by RNase T1 fingerprinting. Hybridization of purified RNAs to restriction endonuclease digests of NR1 DNA indicates that most are derived from the resistance transfer factor region of the plasmid genome. One RNA was found to be coded by the transposable tetracycline resistance element Tn10, and several are associated with DNA fragments that contain origins of replication.
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PMID:Low molecular weight RNA species encoded by a multiple drug resistance plasmid. 35 92

Poly(A)-containing messenger RNA isolated from rabbit reticulocytes as estimated by periodate oxidation and condensation with [3H]isoniazid has two oxidizable end groups per molecule of mol. wt. 220000. When the mRNA is subjected to stepwise degradation by beta-elimination, only one oxidizable end-group is found. This indicates that one of the 2',3' hydroxyl end-groups is linked through the normal 3'--5' phosphodiester bond, but that the other is linked in such a way that after stepwise degradation no new 2',3 hydroxyl group is revealed. This structure could be a 5'-linked 5'-phospho di- or tri-ester. On digestion with ribonuclease the isoniazid-labelled RNA produced oligonucleotide hydrazones consistent with a poly(A) sequence at the 3' end plus fragments that are not found after stepwise degradation. These fragments have a charge of --6 and --8 from pancreatic ribonuclease or --7 from ribonuclease T1 digestion. These charges are changed to --3.4 and --4.1 after pancreatic ribonuclease, ribonuclease T2 and alkaline phosphatase digestion. methyl-3H-labelled-poly(A)-containing RNA isolated from late erythroid cells contain a methyl-labelled fragment resistant to endonuclease and phosphodiesterase II digestion. After digestion with phosphodiesterase I this fragment produces methyl-3 H-labelled nucleotides with the electrophoretic mobility of pm7G and pAm. It is concluded that globin mRNA has the 5' sequences m7G(5')ppp'AmpYpGp ... and m7G(5')pppAmpApGpYp.
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PMID:The nature of the 5'-linked 5' nucleotide sequence at the 5' end of rabbit globin messenger ribonucleic acid. 94 25

In wild-type mycelial cultures of Neurospora crassa under Pi-limited conditions, alkaline phosphatase, cyclic phosphodiesterases I, II, III, and IV, 5'-nucleotidase, acid and alkaline nucleases, RNase N1, and a newly detected endonuclease were secreted into the culture media. These enzymes were either not produced or were produced in very reduced levels in mutants nuc-1, -2, -3, -4, -5, -6, and -7 and cpd-4. The proteins were examined by polyacrylamide gel electrophoresis in a manner which allowed the identification of each of them.
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PMID:Characterization of Pi-repressible enzymes secreted in culture media by Neurospora crassa wild-type cells and null-type mutants. 282 Sep 43

A nuclease S1 mapping procedure was used to identify sites accessible to nucleases in the 3'-noncoding region of the rabbit globin mRNAs. A complex structure was evident in the alpha-globin species, with one highly accessible single-stranded site, large portions in an accessible double-stranded configuration, and a portion not accessible to any of the nucleases. In the beta-globin mRNA, the region was more uniformly accessible to RNase T1 and to a cobra venom enzyme specific for double-stranded RNA, but it had only a single site highly accessible to a bulkier Neurospora endonuclease. The patterns of cleavage were nearly identical in the deproteinized mRNAs and in the mRNAs associated with polyribosomes in reticulocyte extracts. In both species, a zone of secondary structure occurred around the poly(A) junction. In each species, virtually all the molecules had a poly(A) sequence of at least 20-25 AMP residues. A periodicity in poly(A) size distribution was observed. These results indicate that the beginning of this sequence is well protected against degradation inside the cell and that zones of partial protection occur at measured intervals. In crude extracts, where the poly(A) is covered with proteins, this sequence was protected against nuclease digestion.
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PMID:Structural features in the 3'-terminal region of polyribosome-bound rabbit globin messenger RNAs. 300 Oct 55

Verticillium agaricinum when grown for 60 min under near-UV irradiation (366 nm) followed by 24 h in darkness produced maximal activity of a number of nucleic acid enzymes (DNase I, endonuclease, nuclease, RNase A, and RNase T1). Total protein and nucleic acid on the other hand showed a decrease under the same conditions. The nucleic acid enzymes which are involved in reversible reactions seem to favour nucleic acid degradation in this study.
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PMID:Effect of near-UV (366 nm) on the activity of certain nucleic acid enzymes in Verticillium agaricinum. 300 7

Accessible sites in the 5' noncoding region of the rabbit alpha- and beta-globin mRNAs were identified and compared in deproteinized RNA and in the mRNAs engaged in translation in the reticulocyte lysate. Preparations of RNA and lysate were subjected to limited nuclease digestion by RNase T1 and Neurospora endonuclease, and the cleavage sites were analyzed by a nuclease S1 mapping procedure. The free alpha-globin mRNA contained few nuclease-sensitive sites and its initiation codon AUG was masked. The free beta-globin mRNA contained a larger number of accessible sites and its AUG was highly exposed. The distribution of sensitive sites differed considerably in the lysate. In both mRNA species, a site near the 5' terminus became the one most accessible to Neurospora endonuclease. Also the accessibility of the AUG in beta-globin mRNA decreased considerably. The distribution of accessible sites in the lysate was the same when the mRNAs were undergoing rapid initiation and when initiation became limited after prolonged incubation. Inhibition of initiation by the cap analogue 7-methylguanosine 5'-triphosphate was accompanied by increased sensitivity of some of the sites in both mRNA species. One of the accessible sites in each mRNA species had a sequence complementary to the 3'-terminal portion of the 18S ribosomal RNA.
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PMID:Structural features of the 5' noncoding region of the rabbit globin messenger RNAs engaged in translation. 300 32

A DNA fraction enriched in tRNA genes has been prepared by CsCl density gradient centrifugation of Xenopus laevis DNA in the presence of actinomycin D. This DNA fraction was cut with the restriction endonuclease EcoRI and the fragments 800-900 base pairs in size were cloned into the plasmid pBR325. Recombinant DNAs were screened by hybridization to labeled tRNA and for the ability to support transcription in vitro. The entire sequence of one fragment was determined by sequencing the ends of an overlapping set of deletion fragments. A sequence homologous to tRNAVal from mammalian sources was found in this fragment and it was shown that this sequence corresponds to the region of the fragment that is transcribed. The cloned fragment was also transcribed in vivo after injection into X. laevis oocytes. The RNA that was synthesized in the oocytes was digested with ribonuclease T1 and the oligonucleotides were separated to produce a two-dimensional fingerprint. The results of the analysis of the oligonucleotides are consistent with the sequence determined for the tRNAVal gene. The X. laevis genome has 200-250 copies of the 892 base pair EcoRI fragment and additional copies of a 4100 base pair EcoRI fragment that each contain a tRNAVal gene. Digestion of X. laevis DNA with several other restriction endonucleases reveals that the cloned fragment that contains the tRNAVal gene is part of a longer sequence element that is tandemly repeated in the genome.
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PMID:Sequence and transcription of tRNAVal gene from Xenopus laevis. 380 87

The avian Fujinami sarcoma virus (FSV) contains a hybrid transforming gene (delta gag-fps) with a 5' 1.3-kb portion derived from the gag gene of avian retroviruses and a 3' 2.8-kb portion (fps) derived from a cellular prototype. A lambda recombinant DNA clone carrying fps sequences within a 16-kb insert of cellular DNA, termed lambda proto-fps clone 12, has been selected from a chicken DNA library for comparison with the viral onc gene. Mapping of endonuclease-resistant proto-fps DNA fragments and hybridization with cloned viral DNA located FSV-related sequences at the 3' end of the insert within a region of about 4.25 kb. Alignment of endonuclease-resistant proto-fps and viral DNA fragments relative to common RNase T1-resistant oligonucleotide sequences of viral RNA, identified by fingerprinting DNA-RNA hybrids, indicated: (i) that proto-fps is colinear with viral fps but is interrupted by 1.75 kb of scattered sequences unrelated to viral fps; (ii) that among the nine endonuclease sites compared, proto-fps and viral fps share one PvuII, one BamHI, and possibly a Kpn1 site at homologous locations, and that they each have unique endonuclease sites and common sites at unique locations; (iii) that within 12 kb upstream from the 5' boundary of overlap with viral fps, proto-fps lacks gag-related sequences; and (iv) that proto-fps clone 12, like several others isolated by us, lacks at the 3' end an equivalent of the 3' 10 to 20% of viral fps. The eight endonuclease site-map coordinates of proto-fps and viral DNA also divided 44 fps oligonucleotides of viral RNA into 9 map segments. We conclude that the onc gene of FSV differs from proto-fps in delta gag and in multiple point mutations, compatible with a transforming function for the viral gene and a normal function for the cellular sequence homolog. Since proto-fps is unrelated to essential virion genes, the onc gene of FSV must have originated from cellular proto-fps by rare, illegitimate recombination.
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PMID:Structural relationship between the chicken DNA locus, proto-fps, and the transforming gene of Fujinami sarcoma virus, delta gag-fps. 631 Aug 87

The complete nucleotide sequence of the mRNA for the outer membrane lipoprotein from Escherichia coli has been determined. All the ribonuclease T1 and ribonuclease A fragments obtained from the mRNA were connected with DNA sequencing of restriction endonuclease fragments of the cloned lipoprotein gene. The mRNA consists of 322 nucleotides, and there are 38 and 50 nucleotides in the 5' and 3' end untranslated regions, respectively. The mRNA has several unique features: (a) Out of 50 possible codons for 15 amino acids in the prolipoprotein only 25 codons are used, and all of these appear to be read by the major isoaccepting species of tRNAs for individual amino acids. (b) In the first 64 nucleotides from the 5' end, there are no obvious secondary structures. On the other hand, between the 65th nucleotide and the 3' end, 85% of the nucleotides are involved in the formation of secondary structures, with nine stable stem-and-loop structures. (c) There are many repeating sequences including one repeat of 40 nucleotides. (d) There are a few other features which could be important for efficient translation of the mRNA.
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PMID:Messenger ribonucleic acid of the lipoprotein of the Escherichia coli outer membrane. II. The complete nucleotide sequence. 676 42


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