Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.26.4 (RNase H)
 2,751 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have examined the relative transcript levels of the junB and c-jun proto-oncogenes during development of the mouse testis. junB and c-jun mRNA levels are low in total RNA from intact immature or mature testes. Dissociation of testicular cells, however, increases the levels of junB and c-jun mRNAs, with higher increases in the dissociated cells from testes of 8-day-old mice than from 17-day-old or sexually mature mice. These differences in junB and c-jun mRNA levels localize to specific cell types. In testes from 8-day-old mice, the mRNA levels for both proto-oncogenes are higher in type B spermatogonia and in the interstitial cell fraction than in type A spermatogonia. In testes of 17-day-old mice, the highest mRNA levels for both proto-oncogenes are seen in preleptotene spermatocytes and interstitial cells, with decreasing levels in leptotene/zygotene spermatocytes and prepuberal pachytene spermatocytes. junB and c-jun mRNAs are nearly undetectable in pachytene spermatocytes, round spermatids, and residual bodies/cytoplasts. The increased junB mRNA levels originate not only from the expected 2.1-kilobase transcript but from a more slowly migrating transcript of about 2.3 kilobases. RNase H analysis demonstrates that this migration change was due to an increase in mRNA polyadenylation. The low levels of junB and c-jun mRNAs in intact testes and the much higher levels in isolated cells from identical testes suggest that the disruption of cell-to-cell contact increases the amount of junB and c-jun transcripts in specific cells of the testis. Coupled with this increase, structural changes are seen with the junB mRNA.
 ...
PMID:Increased levels of junB and c-jun mRNAs in male germ cells following testicular cell dissociation. Maximal stimulation in prepuberal animals. 170 Jul 82

Oligonucleotide N3'-->P5'phosphoramidates are a new and promising class of antisense agents. Here we report biological properties of phosphoramidate oligonucleotides targeted against the human T cell leukemia virus type-I Tax protein, the major transcriptional transactivator of this human retrovirus. Isosequential phosphorothioate oligodeoxynucleotides and uniformly modified and chimeric phosphoramidate oligodeoxynucleotides containing six central phosphodiester linkages are all quite stable in cell nuclei. The uniformly modified anti-tax phosphoramidate oligodeoxynucleotide does not activate nuclear RNase H, as was shown by RNase protection assay. In contrast, the chimeric phosphoramidate-phosphodiester oligodeoxynucleotide is an efficient activator of RNase H. The presence of one or two mismatched nucleotides in the phosphodiester portion of oligonucleotides affected this activation only negligibly. When introduced into tax-transformed fibroblasts ex vivo, only the uniformly modified anti-tax phosphoramidate oligodeoxynucleotide caused a sequence-dependent reduction in the Tax protein level. Neither the chimeric phosphoramidate nor the phosphorothioate oligodeoxynucleotides significantly reduced tax expression under similar experimental conditions.
 ...
PMID:RNase H-independent antisense activity of oligonucleotide N3 '--> P5 ' phosphoramidates. 901 28

Cauliflower mosaic virus (CaMV) transactivator/viroplasmin (Tav) is an essential multifunctional viral protein. Dissection of Tav by deletion mutagenesis revealed that the central region is essential for CaMV replication in single cells but that the N- and C-terminal parts are not. Strains with mutations in the central region were defective in the translational transactivator function and could be complemented by coexpressing Gag (capsid protein precursor) and Pol (polyprotein with protease, reverse transcriptase, and RNase H activity) from separate monocistronic plasmids. In contrast, total omission of Tav was only partially complemented by Gag and Pol overexpression from separate plasmids. These results indicate that CaMV basic replication requires both Tav-activated polycistronic translation and some posttranslational function(s) of Tav that is not affected by the deletions in the central region of Tav.
 ...
PMID:Dissection of cauliflower mosaic virus transactivator/viroplasmin reveals distinct essential functions in basic virus replication. 1285 28

SUMMARY Taxonomic relationship: Cauliflower mosaic virus (CaMV) is the type member of the Caulimovirus genus in the Caulimoviridae family, which comprises five other genera. CaMV replicates its DNA genome by reverse transcription of a pregenomic RNA and thus belongs to the pararetrovirus supergroup, which includes the Hepadnaviridae family infecting vertebrates. Physical properties: Virions are non-enveloped isometric particles, 53 nm in diameter (Fig. 1). They are constituted by 420 capsid protein subunits organized following T= 7 icosahedral symmetry (Cheng, R.H., Olson, N.H. and Baker, T.S. (1992) Cauliflower mosaic virus: a 420 subunit (T= 7), multilayer structure. Virology, 16, 655-668). The genome consists of a double-stranded circular DNA of approximately 8000 bp that is embedded in the inner surface of the capsid. Viral proteins: The CaMV genome encodes six proteins, a cell-to-cell movement protein (P1), two aphid transmission factors (P2 and P3), the precursor of the capsid proteins (P4), a polyprotein precursor of proteinase, reverse transcriptase and ribonuclease H (P5) and an inclusion body protein/translation transactivator (P6). Hosts: The host range of CaMV is limited to plants of the Cruciferae family, i.e. Brassicae species and Arabidopsis thaliana, but some viral strains can also infect solanaceous plants. In nature, CaMV is transmitted by aphids in a non-circulative manner.
 ...
PMID:Cauliflower mosaic virus: still in the news. 2056 49

A disease of Rudbeckia hirta (Black-eyed Susan), characterized by severe flower deformation, was observed in Minnesota during 2010-2016. A previously undescribed virus species, named Rudbeckia flower distortion virus (RuFDV, family Caulimoviridae, genus unassigned), was determined to be the causal agent of the disease. Symptoms induced by RuFDV infection resemble those characteristic of phytoplasma-induced diseases, but no phytoplasmas were detected in RuFDV-infected R. hirta. The virus, and the disease were transmitted readily by mechanical inoculation and by the aphid Myzus persicae, but only to R. hirta. Virions of RuFDV are icosahedral, 42-45nm in diameter, and contain a circular 8222bp dsDNA genome containing seven open reading frames (ORFs). The ORFs 2-6 have 28-52% amino acid sequence identity to the movement protein (MP), coat protein (CP), aspartic protease (AP), reverse transcriptase (RT) and RNase H, and translational transactivator (TA) domains of known caulimoviruses. The two remaining ORFs (1 and 7) have no significant amino acid sequence similarity to known viruses. Although the RuFDV ORF 6 is significantly truncated relative to those of other known caulimoviruses, neither this nor the concomitant absence of characteristic virus-encoded cytoplasmic inclusion bodies appears to adversely affect aphid transmission of this virus. Phylogenetic analysis based on the sequence of the RT region revealed no close relationship to known members of the family Caulimoviridae. Based on sequence similarity, genome organization and phylogenetic relatedness, RuFDV appears to be distinct from any currently recognized taxonomic grouping in the family Caulimoviridae.
 ...
PMID:Identification, transmission and genomic characterization of a new member of the family Caulimoviridae causing a flower distortion disease of Rudbeckia hirta. 2855

We have characterized the complete genome of a novel circular double-stranded DNA virus, tentatively named Dioscorea nummularia-associated virus (DNUaV), infecting Dioscorea nummularia originating from Samoa. The genome of DNUaV comprised 8139 bp and contained four putative open reading frames (ORFs). ORFs 1 and 2 had no identifiable conserved domains, while ORF 3 had conserved motifs typical of viruses within the family Caulimoviridae including coat protein, movement protein, aspartic protease, reverse transcriptase and ribonuclease H. A transactivator domain, similar to that present in members of several caulimoviridae genera, was also identified in the putative ORF 4. The genome size, organization, and presence of conserved amino acid domains are similar to other viruses in the family Caulimoviridae. However, based on nucleotide sequence similarity and phylogenetic analysis, DNUaV appears to be a distinct novel member of the family and may represent a new genus.
 ...
PMID:Characterization of a novel member of the family Caulimoviridae infecting Dioscorea nummularia in the Pacific, which may represent a new genus of dsDNA plant viruses. 3020 72