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L Pinck

Publications and source records attributed to L Pinck.

At least 37 records · Page 2Linked to original sources
PubMed1991

Alfalfa mosaic virus RNA3 mutants do not replicate in transgenic plants expressing RNA3-specific genes.

The RNA3 of alfalfa mosaic virus (AIMV) encodes the P3 protein and the viral coat protein (CP). RNA3 molecules transcribed in vitro replicated in protoplasts and plants when inoculated in mixtures with AIMV RNA1, RNA2 and CP. Transcripts with a deletion or inversion in the P3 gene replicated well in protoplasts but not in transgenic plants transformed with the P3 gene. Transgenic plants expressing the CP gene became infected after inoculation with a mixture of RNA1, RNA2 and wild-type RNA3 transcripts without addition of CP to the inoculum. Transcripts with a deletion in the CP gene replicated at a reduced level in protoplasts but not in CP-transformed plants. This suggests that P3 and CP are both required for cell-to-cell spread of AIMV and that mutations in the inoculum RNA could not be complemented in trans by the wild-type chimeric nuclear genes.

Blotting, Northern↗
PubMed1990

Biologically active transcripts of alfalfa mosaic virus RNA3.

Transcripts of the bicistronic RNA3 of alfalfa mosaic virus were synthesized using the in vitro T7 run-off transcription system. Synthetic RNA3 containing one additional G nucleotide at the 5' end were found to be infectious when coinoculated with RNA1 and RNA2 and coat protein.

Base Sequence↗
PubMed1990

RNA2 of grapevine fanleaf virus: sequence analysis and coat protein cistron location.

The nucleotide sequence of the genomic RNA2 (3774 nucleotides) of grapevine fanleaf virus strain F13 was determined from overlapping cDNA clones and its genetic organization was deduced. Two rapid and efficient methods were used for cDNA cloning of the 5' region of RNA2. The complete sequence contained only one long open reading frame of 3555 nucleotides (1184 codons, 131K product). The analysis of the N-terminal sequence of purified coat protein (CP) and identification of its C-terminal residue have allowed the CP cistron to be precisely positioned within the polyprotein. The CP produced by proteolytic cleavage at the Arg/Gly site between residues 680 and 681 contains 504 amino acids (Mr 56019) and has hydrophobic properties. The Arg/Gly cleavage site deduced by N-terminal amino acid sequence analysis is the first for a nepovirus coat protein and for plant viruses expressing their genomic RNAs by polyprotein synthesis. Comparison of GFLV RNA2 with M RNA of cowpea mosaic comovirus and with RNA2 of two closely related nepoviruses, tomato black ring virus and Hungarian grapevine chrome mosaic virus, showed strong similarities among the 3' non-coding regions but less similarity among the 5' end non-coding sequences than reported among other nepovirus RNAs.

Amino Acid Sequence↗
PubMed1989

Competitive multiplication of RNA3 species of different strains of alfalfa mosaic virus.

Competition between RNA3 from alfalfa mosaic virus (AlMV) strain S (RNA3-S), strain B (RNA3-B) and strain 425L (RNA3-L) was studied. The identification of the RNA3 species multiplying in infected leaves was possible since the RNA3 5' non-coding leader sequences in strains S, B and 425L differ in length. RNA3 present in total RNA from infected tobacco leaves was detected, and strains were identified from the length of the cDNA reverse-transcribed from RNA primed with a specific oligonucleotide. In competition experiments the inoculum, containing known amounts of RNA1, 2, 3 and 4 of one strain, was complemented with various amounts of heterologous RNA3 and inoculated to a systemic host. It is shown that RNA3-S was better replicated in vivo by the AlMV replicase of strain B than was RNA3-B itself, and to a lesser extent better replicated by the AlMV replicase of strain L than was RNA-L. Comparison of genetic information carried by the RNA3 species present in the inoculum suggests that the more efficient multiplication of RNA3-S is related to the structure of the leader sequence of RNA3-S.

Amino Acid Sequence↗
PubMed1989

The nucleotide sequence of satellite RNA in grapevine fanleaf virus, strain F13.

The nucleotide sequence of cDNA copies of grapevine fanleaf virus (strain F13) satellite RNA has been determined. The primary structure obtained was 1114 nucleotides in length, excluding the poly(A) tail, and contained only one long open reading frame encoding a 341 residue, highly hydrophilic polypeptide of Mr37275. The coding sequence was bordered by a leader of 14 nucleotides and a 3'-terminal non-coding region of 74 nucleotides. No homology has been found with small satellite RNAs associated with other nepoviruses. Two limited homologies of eight nucleotides have been detected between the satellite RNA in grapevine fanleaf virus and those in tomato black ring virus, and a consensus sequence U.G/UGAAAAU/AU/AU/A at the 5' end of nepovirus RNAs is reported. A less extended consensus exists in this region in comovirus and picornavirus RNA.

Amino Acid Sequence↗
PubMed1985

Translational discrimination between the four RNAs of alfalfa mosaic virus. A quantitative evaluation.

In an attempt to relate the translational characteristics of alfalfa mosaic virus (A1MV) RNAs to their structure [Ravelonandro et al. (1983) Nucleic Acids Res. 11, 2815-2826; Gehrke et al. (1983) Biochemistry 22, 5157-5164] we measured the relative affinities (discrimination ratios) of these RNAs for the initiation complex, in the wheat germ extract and in the nuclease-treated reticulocyte lysate, using a competition method designed by Brendler et al. [(1981) J. Biol. Chem. 256, 11747-11754]. As a prerequisite of this study we ascertained that the molecular mass distribution of the translation products was independent of RNA concentration in both translation systems. In the wheat germ extract the discrimination ratios are very similar for two strains of A1MV (S and B) which differ mainly by the presence (strain S) or absence (strain B) of a stable 5'-proximal hairpin. Hence this structure has no bearing on discrimination. Taking the affinity of RNA 3 as reference, the following orders of magnitude are found for the affinities of the different RNAs in the wheat germ: RNA 3, 1.0; RNA 1, 10; RNA 2, 60; RNA 4, 150. In the reticulocyte lysate the discrimination ratios are not significantly different from the wheat germ. Thus it seems that the mechanism of discrimination is essentially the same in the two translation systems, despite a difference in rate-limitation.

Animals↗
PubMed1985

Cap accessibility correlates with the initiation efficiency of alfalfa mosaic virus RNAs.

The rate of cap removal from the alfalfa mosaic virus (A1MV) RNAs with tobacco acid pyrophosphatase (TAP) depends on the RNA species. At 37 degrees C and in the absence of divalent cation, RNA 3 reacts more slowly than the other three, which are decapped at similar rates. In the presence of magnesium, at 25 degrees C, TAP also discriminates against RNA 1. Thus the order of reactivity with TAP largely mimics the hierarchy of initiation efficiencies of the A1MV RNAs (Godefroy-Colburn et al., preceding paper in this journal). Our interpretation of these findings is that cap accessibility is what limits the rate of reaction with initiation factors as well as with TAP. In this hypothesis, translational discrimination between naturally capped messages would be related to the rate of 'breathing' of their 5' ends.

Animals↗
PubMed1984

Complete nucleotide sequence of RNA 3 from alfalfa mosaic virus, strain S.

We report the sequence of RNA 3 from strain S of Alfalfa mosaic virus (2,055 nucleotides). This RNA codes for a 32.4 kd protein (P3) and for the 24 kd coat protein (P4). The largest part of the sequence was established using RNA sequencing methods. The completion of the sequence in the region coding for P3 was achieved with cloned cDNA synthesized after priming at internal sites of RNA 3. Comparison of the RNA sequences coding P3 and P4 proteins in strain S with those reported in the literature for strain 425 revealed a higher amino acid substitution rate (3%) for P3 than for P4 (congruent to 1%) despite a similar average base substitution of 3-4% in these regions. In P3, two out of nine amino acid changes occur in hydrophilic regions. The amino acid changes in P4 do not modify the local hydrophilicity distribution. The intercistronic region displays a low degree of base substitution (2%) when compared with the untranslated 3'-end region (3.6%) or the 5'-end leader region (8%), the average substitution rate being 3.2%.

Amino Acid Sequence↗
PubMed1983

Structure of the 5'-terminal untranslated region of the genomic RNAs from two strains of alfalfa mosaic virus.

We report the sequences of the 5'-terminal regions of the 3 Alfalfa Mosaic Virus genomic RNAs for the Strasbourg strain (AlMV-S) and for a new isolate, AlMV-B; they are compared to similar data obtained by Koper-Zwarthoff et al. (Nucleic Acids Res. 1980, 8, 5635-5647) for strain 425. The structure of these leaders is highly conserved in RNAs 1 and 2. The length of the leader is 102, 100 and 101 nucleotides in RNA1 for strains S, B and 425 respectively; 55 and 56 in RNA2 for strains S and B respectively. In RNA3 however, there are important differences near the 5'-terminus between strain S and the other two: The total leader length is 258 nucleotides for strain S and 242 for strain B. The secondary structure models show a conserved hairpin near the 5'-end of each genomic RNA of AlMV-S. This hairpin is inexistent in RNA3 of the B and 425 strains. The degree of base-pairing increases with leader length. The initiator codon is located in a single stranded region in RNA2 whereas it is found in a hairpin stem in RNA 3.

Base Sequence↗
PubMed1981

Binding of ribosomes to the 5' leader sequence (N = 258) of RNA 3 from alfalfa mosaic virus.

RNA 3 of alfalfa mosaic virus (AlMV) contains information for two genes: near the 5' end an active gene coding for a 35 Kd protein and, near the 3' end, a silent gene coding for viral coat protein. We have determined a sequence of 318 nucleotides which contains the potential initiation codon for the 35 Kd protein at 258 nucleotides from the 5' end. This long leader sequence can form initiation complexes containing three 80 S ribosomes. A shorter species of RNA, corresponding to a molecule of RNA 3 lacking the cap and the first 154 nucleotides (RNA 3') has been isolated. The remaining leader sequence of 104 nucleotides in RNA 3' forms a single 80 S initiation complex with wheat germ ribosomes. The location of the regions of the leader sequence of RNA 3 involved in initiation complex formation with 80 S ribosomes is reported.

Base Sequence↗
PubMed1979

Formation of ribosome-RNA initiation complexes with alfalfa mosaic virus RNA 4 and RNA 3.

RNA 4 of alfalfa mosaic virus (AMV) is a monocistronic messenger for the coat protein. We have determined the sequence of the 40 +/- 2 nucleotides in RNA 4 that were protected in the initiation complex formed with wheat germ 80 S ribosomes from digestion by T1 or pancreatic ribonucleases. The AUG coat protein initiation codon was near the middle of this protected region. We have found two ribosome-binding sites in RNA 3. The principal one, near the 5' end, is the initiation site for the major translation product, a 35,000 dalton protein. The second site binds ribosomes only weakly, at the beginning of the "silent" coat protein cistron, and is similar but not identical to the initiation site protection site is discussed.

Base Sequence↗
PubMed1975

Analysis of the pancreatic-ribonuclease-digestion products of alfalfa-mosaic-virus ribonucleic acid. Sequence homologies between the different RNAs.

Alfalfa mosaic virus (AMV) genome consists of three pieces of RNA (24-S, 20-S and 17-s RNA). For infectivity these three RNAs and the coat protein are required. In the absence of coat protein, infectivity is obtained by adding the 12-S RNA also normally present in the virus. This 12-S RNA represents the message for coat protein. Thus a redundancy of the gene for coat protein exists between 12-S RNA and one of the other RNAs. Sequence analysis of the oligonucleotides resulting from pancreatic ribonuclease digestion of the AMV RNAs indicates that the nucleotide sequence of 12-S RNA occurs in 17-S RNA. Analysis of the pancreatic ribonuclease digestion products of the two larger alfalfa mosaic virus RNAs (20-S and 24-S RNA) shows some oligonucleotides containing seven, eight and nine nucleotides with the same structure present in both RNAs. The possibility of a limited nucleotide sequence homology between these two RNAs is discussed. The comparison of the RNase digestion products of 20-S and 24-S RNA with those of 12-S or 17-S RNA revealed no homologous oligonucleotides, thus the origin of 12-S RNA appears to be 17-S RNA.

Base Sequence↗