Disease relevance of Rnaseh1

• Use of thermostable and Escherichia coli RNase H in RNA mapping studies [1].
• Ribonuclease H activity in rat mammary gland during the lactation cycle and in R3230AC mammary adenocarcinoma [2].

High impact information on Rnaseh1

• Ribonucleotide-rich regions can be degraded to generate partially single-stranded molecules by RNase H treatment in vitro or during DNA extraction from crude mitochondria [3].
• Poly(A)- RNA and poly(A)+ RNA from which tails were removed by RNase H digestion were much more effective than poly(A)+ RNA in expressing AVP in the magnocellular hypothalamic neurons and in raising urine osmolarity [4].
• The present study investigates the protein binding site within the 27-base HIPBS, first by using specific cleavages of HIPBS and its flanking sequences with antisense oligodeoxynucleotides and RNase H and then by using mutational analysis of the binding properties [5].
• In addition to the previously identified DNA polymerase alpha, DNA primase, 3'-5' exonuclease, RNase H, and DNA methylase were all recovered at significant levels (20-30% of total nuclear activity) in nuclear matrix isolated from regenerating rat liver during maximal in vivo replication (22 h post-hepatectomy) [6].
• Mild sonication resulted in a significant release of all of these activities except RNase H. A major portion of the matrix-solubilized DNA polymerase alpha, DNA primase, 3'-5' exonuclease, and DNA methylase activities cosedimented on sucrose gradients between approximately 8-12 S [6].

Biological context of Rnaseh1

• Moreover, protein binding to this fragment was prevented with an antisense oligonucleotide directed against bases 1551-1579 and subsequent RNase H digestion [7].
• In vivo transfection of antisense ACE ODNs into intact uninjured rat carotid artery resulted in a significant reduction of vascular ACE activity, and cotransfection of HMG-1 and RNase H showed further reduction [8].
• A series of oligonucleotide-directed ribonuclease H mapping experiments determined that the two mRNA species differ at their 3' ends in the extent of polyadenylation [9].
• Inhibition of c-myc was specifically achieved by using phosphorodiamidate Morpholino oligomer (PMOs), a novel, non-toxic antisense DNA chemistry for inhibition of gene expression by an RNase H-independent mechanism [10].
• Initial experiments using oligo (dT)-directed RNase H hydrolysis indicated that the two mRNAs have poly [A+] tails of identical length [11].

Anatomical context of Rnaseh1

• Removal of the ribonucleotides with calf thymus ribonuclease H, followed by denaturation of the mitochondrial DNA and analysis of the single-strand fragment lengths in the electron microscope, showed that the ribonucleotides were randomly located on both strands of the DNA [12].
• Multiple forms of ribonuclease H from rat liver cytosol [13].
• These results indicate that multiple forms of ribonuclease H exist in different regions of rat liver cells [14].

Associations of Rnaseh1 with chemical compounds

• The enzyme cannot hydrolyze di- or trinucleotides, lacks RNase-H activity, and will not liberate thymine dimers from UV-irradiated DNA [15].
• Change of ribonuclease H activity from rat liver nuclei by thioacetamide: preferential increase in the activity of magnesium-dependent ribonuclease H [16].
• Among the enzymes from these two fractions in the nuclei, the activity of the Mg2+-dependent RNase H which binds to DNA-cellulose increased several-fold within 24 h of a single injection of thioacetamide [17].

Enzymatic interactions of Rnaseh1

• RNase H was used to hydrolyze IGF-I mRNAs at the point of annealment with the oligomers [18].

Other interactions of Rnaseh1

• RNase H cleavage and Northern blot analysis of the 3'-ends established that rapid deadenylation occurred concomitantly with the rapid decay of the betaG-GA mRNA in cells grown in normal medium [19].
• By contrast, RNase H analysis revealed a transient, T3-induced increase in P450R mRNA poly(A) tail, from approximately 100 to approximately 205 A [20].
• RNase protection, primer extension, RACE PCR and ribonuclease H mapping established the complete structure of the 5' end of class 1 and class 2 IGF-I mRNAs [21].
• Both alpha 1b-adrenergic receptor mRNAs appear to share extensive regions of homology, therefore, we used oligonucleotide-directed ribonuclease H mapping to detect sequence differences between the two transcripts [11].

Analytical, diagnostic and therapeutic context of Rnaseh1

• We compared, in this study, the structure of mRNAs encoding SPTm and SPTp by comparison of the sizes after removal of poly(A) tail by ribonuclease H and by means of RNA blot analysis and S1 nuclease protection assay [22].
• To determine whether these changes occurred in the 5' (alternate transcriptional start site or splicing)- or 3' (altered polyadenylation)-end of the molecules, mRNAs were cleaved using oligonucleotide-directed RNase-H digestion, and the fragments were analyzed by Northern blot, using probes specific to the 5'- and 3'-segments of each transcript [23].
• We have used primer extension analysis, reverse transcriptase associated with polymerase chain reaction, and RNase H digestion to show that these two mRNA species have the same structural features, including 5'- and 3'-ends, and poly(A) tail length [24].
• Two forms of RNase H were separated from rat liver nuclei by affinity chromatography using a DNA-cellulose column [17].

References