scholarly journals Multiple L double-stranded RNA species of Saccharomyces cerevisiae: evidence for separate encapsidation.

1984 ◽  
Vol 4 (1) ◽  
pp. 92-100 ◽  
Author(s):  
D J Thiele ◽  
E M Hannig ◽  
M J Leibowitz
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polymerase Activity ◽  
Double Stranded Rna ◽  
Molecular Weights ◽  
Major Species ◽  
Distinct Sequence ◽  
Rna Polymerase Activity ◽  
Protein Components ◽  
Dsrna Species

The L double-stranded (ds) RNA component of Saccharomyces cerevisiae may contain up to three dsRNA species, each with a distinct sequence but with identical molecular weights. These dsRNAs have been separated from each other by denaturation and polyacrylamide gel electrophoresis. The 3' terminal sequences of the major species, LA dsRNA, were determined. Secondary structural analysis supported the presence of two stem and loop structures at the 3' terminus of the LA positive strand. In strain T132B NK-3, both the LA and LC species are virion encapsidated. Two distinct classes of virions were purified from this strain, each with a different RNA polymerase activity and with distinct protein components. The heavy virions harbored LA dsRNA, whereas the LC dsRNA species co purified with the light virion peak. Thus, LA and LC dsRNAs, when present in the same cell, may be separately encapsidated.

Multiple L double-stranded RNA species of Saccharomyces cerevisiae: evidence for separate encapsidation

1984 ◽  
Vol 4 (1) ◽  
pp. 92-100
Author(s):  
D J Thiele ◽  
E M Hannig ◽  
M J Leibowitz
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polymerase Activity ◽  
Double Stranded Rna ◽  
Molecular Weights ◽  
Major Species ◽  
Distinct Sequence ◽  
Rna Polymerase Activity ◽  
Protein Components ◽  
Dsrna Species

The L double-stranded (ds) RNA component of Saccharomyces cerevisiae may contain up to three dsRNA species, each with a distinct sequence but with identical molecular weights. These dsRNAs have been separated from each other by denaturation and polyacrylamide gel electrophoresis. The 3' terminal sequences of the major species, LA dsRNA, were determined. Secondary structural analysis supported the presence of two stem and loop structures at the 3' terminus of the LA positive strand. In strain T132B NK-3, both the LA and LC species are virion encapsidated. Two distinct classes of virions were purified from this strain, each with a different RNA polymerase activity and with distinct protein components. The heavy virions harbored LA dsRNA, whereas the LC dsRNA species co purified with the light virion peak. Thus, LA and LC dsRNAs, when present in the same cell, may be separately encapsidated.

RNA polymerase activity in virions from Ustilago maydis

1984 ◽  
Vol 4 (1) ◽  
pp. 188-194
Author(s):  
B S Ben-Tzvi ◽  
Y Koltin ◽  
M Mevarech ◽  
A Tamarkin
Keyword(s):  
Rna Polymerase ◽  
Viral Genome ◽  
Ustilago Maydis ◽  
Polymerase Activity ◽  
Reaction Products ◽  
Double Stranded Rna ◽  
Rna Molecules ◽  
Rna Transcripts ◽  
Rna Polymerase Activity

RNA polymerase activity is associated with the double-stranded RNA virions of Ustilago maydis. The reaction products of the polymerase activity are single-stranded RNA molecules. The RNA molecules synthesized are homologous to the three classes of double-stranded RNA molecules that typify the viral genome. The single-stranded RNA synthesized is released from the virions. The molecular weight of the single-stranded RNA transcripts is about half the size of the double-stranded RNA segments, and thus, it appears that in the in vitro reaction, full-length transcripts can be obtained.

Subunit studies of coupling factor 1 of bean chloroplasts

1976 ◽  
Vol 54 (5) ◽  
pp. 481-487 ◽  
Author(s):  
M. P. Silvanovich ◽  
R. D. Hill
Keyword(s):  
Amino Acid ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Coupling Factor ◽  
Leaf Extracts ◽  
Molecular Weights ◽  
Major Species ◽  
Chloroplast Coupling Factor ◽  
Coupling Factors

A bean chloroplast coupling factor (CF1) with latent Ca2+-dependent ATPase activity was studied. Immunodiffusion of bean (Phaseolus vulgaris) chloroplast and etioplast coupling factors and spinach coupling factor against antiserum to spinach coupling factor showed partial identity of the bean coupling factor with that of spinach. An immunoelectrophoretic comparison, under dissociating conditions, of bean leaf extracts and spinach extracts containing CF1 subunits (as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis) gave identical results for both extracts. At least six distinct polypeptide species were found. The major species had molecular weights of 42 000, 59 000 and 63 000 daltons. Amino acid analysis of electrophoretically purified bean CF1 gave results similar to those published for spinach CF1.

scholarly journals Thermolabile L-A virus-like particles from pet18 mutants of Saccharomyces cerevisiae.

1986 ◽  
Vol 6 (2) ◽  
pp. 404-410 ◽  
Author(s):  
T Fujimura ◽  
R B Wickner
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Rna Polymerase ◽  
Polymerase Activity ◽  
Nonpermissive Temperature ◽  
Wild Type ◽  
Rna Dependent Rna Polymerase ◽  
Virus Like Particles ◽  
Rna Polymerase Activity ◽  
Lines Of Evidence

pet18 mutations in Saccharomyces cerevisiae confer on the cell the inability to maintain either L-A or M double-stranded RNAs (dsRNAs) at the nonpermissive temperature. In in vitro experiments, we examined the effects of pet18 mutations on the RNA-dependent RNA polymerase activity associated with virus-like particles (VLPs). pet18 mutations caused thermolabile RNA polymerase activity of L-A VLPs, and this thermolability was found to be due to the instability of the L-A VLP structure. The pet18 mutations did not affect RNA polymerase activity of M VLPs. Furthermore, the temperature sensitivity of wild-type L-A RNA polymerase differed substantially from that of M RNA polymerase. From these results, and from other genetic and biochemical lines of evidence which suggest that replication of M dsRNA requires the presence of L-A dsRNA, we propose that the primary effect of the pet18 mutation is on the L-A VLP structure and that the inability of pet18 mutants to maintain M dsRNA comes from the loss of L-A dsRNA.

scholarly journals RNA polymerase activity in virions from Ustilago maydis.

1984 ◽  
Vol 4 (1) ◽  
pp. 188-194 ◽  
Author(s):  
B S Ben-Tzvi ◽  
Y Koltin ◽  
M Mevarech ◽  
A Tamarkin
Keyword(s):  
Rna Polymerase ◽  
Viral Genome ◽  
Ustilago Maydis ◽  
Polymerase Activity ◽  
Reaction Products ◽  
Double Stranded Rna ◽  
Rna Molecules ◽  
Rna Transcripts ◽  
Rna Polymerase Activity

RNA polymerase activity is associated with the double-stranded RNA virions of Ustilago maydis. The reaction products of the polymerase activity are single-stranded RNA molecules. The RNA molecules synthesized are homologous to the three classes of double-stranded RNA molecules that typify the viral genome. The single-stranded RNA synthesized is released from the virions. The molecular weight of the single-stranded RNA transcripts is about half the size of the double-stranded RNA segments, and thus, it appears that in the in vitro reaction, full-length transcripts can be obtained.

scholarly journals Trf4 and Trf5 Proteins of Saccharomyces cerevisiae Exhibit Poly(A) RNA Polymerase Activity but No DNA Polymerase Activity

2005 ◽  
Vol 25 (22) ◽  
pp. 10183-10189 ◽  
Author(s):  
Lajos Haracska ◽  
Robert E. Johnson ◽  
Louise Prakash ◽  
Satya Prakash
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Dna Polymerase ◽  
Protein Complexes ◽  
Polymerase Activity ◽  
Yeast Cells ◽  
Translation Efficiency ◽  
Eukaryotic Dna ◽  
Specific Mrnas ◽  
Rna Polymerase Activity ◽  
The Stability

ABSTRACT The Saccharomyces cerevisiae Trf4 and Trf5 proteins are members of a distinct family of eukaryotic DNA polymerase β-like nucleotidyltransferases, and a template-dependent DNA polymerase activity has been reported for Trf4. To define the nucleotidyltransferase activities associated with Trf4 and Tr5, we purified these proteins from yeast cells and show that whereas both proteins exhibit a robust poly(A) polymerase activity, neither of them shows any evidence of a DNA polymerase activity. The poly(A) polymerase activity, as determined for Trf4, is strictly Mn2+ dependent and highly ATP specific, incorporating AMP onto the free 3′-hydroxyl end of an RNA primer. Unlike the related poly(A) polymerases from other eukaryotes, which are located in the cytoplasm and regulate the stability and translation efficiency of specific mRNAs, the Trf4 and Trf5 proteins are nuclear, and a multiprotein complex associated with Trf4 has been recently shown to polyadenylate a variety of misfolded or inappropriately expressed RNAs which activate their degradation by the exosome. To account for the effects of Trf4/Trf5 proteins on the various aspects of DNA metabolism, including chromosome condensation, DNA replication, and sister chromatid cohesion, we suggest an additional and essential role for the Trf4 and Trf5 protein complexes in generating functional mRNA poly(A) tails in the nucleus.

scholarly journals Association of RNA Polymerase Complexes of the Parasitic Protozoan Cryptosporidium parvum with Virus-Like Particles: Heterogeneous System

2000 ◽  
Vol 74 (13) ◽  
pp. 5788-5795 ◽  
Author(s):  
Nikolai V. Khramtsov ◽  
Steve J. Upton
Keyword(s):  
Rna Polymerase ◽  
Cryptosporidium Parvum ◽  
Rna Virus ◽  
Buoyant Density ◽  
Polymerase Activity ◽  
Parasitic Protozoan ◽  
Double Stranded Rna ◽  
Virus Like Particles ◽  
The Family ◽  
Rna Polymerase Activity

ABSTRACT RNA polymerase complexes were purified from Cryptosporidium parvum, a parasitic protozoan known to infect many species of mammals including humans. Western blot analysis revealed the association of the complexes with two different proteins, encoded by large and small segments of viral double-stranded RNAs. Each complex was found to contain only double-stranded RNA, both double- and single-stranded RNA, or only single-stranded RNA. Maximum RNA-dependent RNA polymerase activity was observed within the complexes containing both double- and single-stranded RNAs. These complexes possessed both transcriptase and replicase polymerase activities. Virus-like particles with a diameter of 31 nm were copurified with RNA polymerase complexes, and buoyant density and polymerase studies suggest that C. parvum harbors a putative double-stranded RNA virus which separately encapsidates the large and small RNA segments. The mechanism of replication and other characteristics of this virus are similar to those of the viruses of the family Partitiviridae, previously identified only in fungi and plants.

scholarly journals RNA-Dependent RNA Polymerase Activity Associated with Endogenous Double-Stranded RNA in Rice

2001 ◽  
Vol 42 (2) ◽  
pp. 197-203 ◽  
Author(s):  
Hideki Horiuchi ◽  
Tsuyoshi Udagawa ◽  
Ryuichi Koga ◽  
Hiromitsu Moriyama ◽  
Toshiyuki Fukuhara
Keyword(s):  
Rna Polymerase ◽  
Polymerase Activity ◽  
Rna Dependent Rna Polymerase ◽  
Double Stranded Rna ◽  
Rna Polymerase Activity
Sign in / Sign up

Export Citation Format

Share Document