Biomedical subjects

J R Edwardson

Publications and source records attributed to J R Edwardson.

15 recordsLinked to original sources

PubMed1992

Biological variants of tobacco etch virus that induce morphologically distinct nuclear inclusions.

The presence of distinctive nuclear inclusions has been used for many years as a diagnostic character for tobacco etch virus (TEV). Cytological examinations of isolates of TEV in both weeds and solanaceous crops from areas widely separated geographically have demonstrated the presence of a variety of nuclear inclusions that vary considerably in form. Such inclusions can, in many cases, be related to differences in symptom expression. It is suggested that distinctive nuclear inclusions may be used to select biological variants of TEV that may be useful in the study and manipulation of closely related "strains" of this potyvirus.

Genetic Variation↗

PubMed1992

Viruses of the Potyviridae with non-aphid vectors.

The large majority of members of the family Potyviridae are aphid-transmitted. However, 17 viruses whose vectors are unknown have been classified as members of the genus Potyvirus. Loss of aphid transmissibility has been observed in some strains of several potyviruses. There are currently 11 members of the Potyviridae whose vectors are not aphids. These viruses with non-aphid vectors exhibit most of the characteristics of the family. Viruses of the Potyviridae induce cytoplasmic cylindrical inclusions in their hosts whether their vectors are aphids, non-aphids, or are unknown. The virus genome produces the inclusion protein and thus the viruses have related inclusion body gene sequences. Non-aphid-transmitted viruses of the Potyviridae also are serologically related to aphid-transmitted potyviruses.

Animals↗

PubMed1992

Inclusion bodies.

All viruses in the family Potyviridae which have been studied cytologically (currently 111) induce cylindrical inclusions in host cytoplasm. These inclusions are controlled by portions of the virus genome, therefore, viruses which induce them are related. Viruses in other groups do not induce this type of inclusion. Cylindrical inclusions have come to be recognized as one of the main characteristics of the family Potyviridae. They are used in diagnosis of diseases induced by these viruses. For diagnostic purposes the family can be separated into four subdivisions on the basis of differences in cylindrical inclusion morphologies. Assigning viruses to subdivisions assists in virus identification at the specific and in some instances at the strain level.

Cell Nucleus↗

PubMed1992

Evidence that pepper mottle virus and potato virus Y are distinct viruses: analyses of the coat protein and 3' untranslated sequence of a California isolate of pepper mottle virus.

Pepper mottle virus (PepMoV) is a member of the large and complex genus Potyvirus, and is classically distinguished from other members of the genus by differential host range and cytopathology as well as serology of the coat protein and cytoplasmic inclusion body proteins. Here we report the deduced amino acid sequence of the coat protein of a California potyvirus identified by a variety of classical methods as PepMoV (PepMoV C). Comparison of the 3' untranslated nucleic acid sequence and the deduced coat-protein amino acid sequence of the PepMoV C isolate with those of PVY and other potyviruses indicates that PepMoV C is sufficiently diverged to be considered a distinct virus species. Thus, comparative sequence analyses of the PepMoV C isolate support earlier serological and biological evidence that PepMoV and PVY are distinct viruses.

Amino Acid Sequence↗

PubMed1972