Biomedical subjects

C Fauquet

Publications and source records attributed to C Fauquet.

22 records · Page 2Linked to original sources

PubMed1991

Transient gene expression in cassava using high-velocity microprojectiles.

The bacterial gene encoding beta-glucuronidase (GUS) was transiently expressed in cassava leaves following the introduction of the gene by microparticle bombardment. The DNA expression vector used to introduce the reporter gene is a pUC 19 derivative and consisted of a CaMV 35S promoter (P35S), the GUS coding region and 7S polyadenylation region. Several other promoters and regulating sequences were tested for efficiency in cassava leaves. Two derivatives of the P35S, one including a partial duplication of the upstream region of the P35S and the other containing a tetramer of the octopine synthase enhancer, were found to be expressed at three times the level of the P35S in cassava leaves. The ubiquitin 1 promoter from Arabidopsis thaliana was expressed at the same level as the P35S. No influence on the level of expression was observed when different 3' ends were used. The biolistic transient gene expression system in cassava leaves allows rapid analysis of gene constructs and can serve as a preliminary screen for chimeric gene function in the construction of transgenic cassava plants.

Cloning, Molecular↗

PubMed1986

Evidence that the amino acid composition of the particle proteins of plant viruses is characteristic of the virus group. I. Multidimensional classification of plant viruses.

The amino acid (AA) contents of the coat proteins of 134 plant viruses and strains were classified by principal components analysis. The virus groupings that were obtained correlated well with the classification of Matthews. The relationships of each virus were dependent on the number of AA residues (axis 1) and on the percentage composition of each AA in the proteins (axes 2-4). The classification indicated which data were anomalous and needed confirmation. There seemed to be more anomalies in estimates of protein size than of protein composition.

Amino Acids↗

PubMed1986

Evidence that the amino acid composition of the particle proteins of plant viruses is characteristic of the virus group. II. Discriminant analysis according to structural biological and classification properties of plant viruses.

The amino acid composition (AAC) of the coat proteins (CPs) of 126 plant viruses or strains were analyzed by stepwise discriminant analysis. The criteria chosen for discrimination were: the structure of virus particles (3 clusters); the mode of of transmission of the viruses (6 clusters); and the grouping of viruses according to the classification of the International Committee on Taxonomy of Viruses (23 groups). Statistically significant correlations were obtained with different groups of discriminant amino acids. The results confirm that the AAC of the CPs contains all the information needed for a quantitative classification of plant viruses. These results and possible explanations of these clustering patterns are discussed.

Amino Acids↗

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↗