Rubella virus nonstructural proteins, translated from input genomic RNA as a p200 polyprotein and subsequently processed into p150 and p90 by an intrinsic papain-like thiol protease, are responsible for virus replication. To examine the effect of p200 processing on virus replication and to study the roles of nonstructural proteins in viral RNA synthesis, we introduced into a rubella virus infec...

Influenza A virus possesses a segmented genome of eight negative-sense, single-stranded RNAs. The eight segments have been shown to be represented in approximately equal molar ratios in a virus population; however, the exact copy number of each viral RNA segment per individual virus particles has not been determined. We have established an experimental approach based on multicolor single-molecu...

Partially separated double-stranded RNA from purified Rous sarcoma virus, Schmidt.Ruppin strain, was observed by electron microscopy utilizing 8.M urea and protein monolayer technique. Furthermore, viruses in pair were frequently and viruses with two nuc1eoids were occasionally observed in ultrathin. sectioned specimens of chick cells transformed by RSV. From these results taking other reports ...

We have used molecular hybridization to detect virus-specific RNA in tumors ( I ) , and have found that corresponding neoplasias of murine and human origin exhibit remarkable similarities. Thus, human breast carcinomas contained (2) RNA possessing sequence homology to that of mouse mammary tumor virus (MMTV). This type of RNA was unique to the malignant adenoand medullary-carcinomas, being unde...

Human breast cancers contain an RNA related to that of mouse mammary tumor virus. In 79% of the breast malignancies examined, this type of RNA is a 70S-component encapsulated with RNA-instructed DNA polymerase in a particle possessing the density characteristics of RNA tumor viruses. Further, the DNA synthesized by the human RNA enzyme complex hybridizes specifically with the RNA of mouse mamma...

Cells infected by Rauscher leukemia virus synthesize virus-specific RNA which can be detected by hybridization to the single-stranded DNA copy of the viral RNA. Evidence is provided that virus-specific RNA is present in free and membrane-bound polyribosomes of these cells. The relative content of virus-specific RNA, as measured by hybridization, is 6-10 times less on free polyribosomes than on ...

The present investigation is concerned with the search for RNA-directed DNApolymerase activity in human and hamster melanoma cells in both in vivo tumors and tumor cells grown in tissue culture. The assays and techniques employed are based upon model studies carried out in this laboratory with the enzyme from avian myeloblastoses virus, and feline sarcoma, and lymphoma virus. In recent years, s...

In 1961, Howard Temin began to gather evidence that was inconsistant with the central dogma. Temin, who devoted his life to studying RNA tumor viruses (now known as retroviruses), focused his early work on Rous sarcoma virus (RSV). This RNA virus is capable of transforming normal cells into cancerous cells. Temin felt the best explanation for the virus’s behavior was a model whereby the virus r...