Molecular diversity among five different endogenous primate retroviruses

Area of Science:

• Virology
• Genetics
• Primate Biology

Background:

• Old and New World monkeys harbor genetically transmitted retroviruses, specifically type C and type D viruses.
• These retroviral isolates from various primate species (baboons, macaques, owl monkeys, langurs, squirrel monkeys) are genetically distinct.

Purpose of the Study:

• To investigate the genetic relatedness and structural characteristics of endogenous primate retroviruses.
• To determine the diversity and evolutionary relationships among type C and type D retroviruses in primates.

Main Methods:

• Nucleic acid hybridization to assess genomic relatedness.
• Analysis of virion-associated proteins using gel filtration and electrophoresis.
• Two-dimensional tryptic peptide mapping to determine primary protein structure.
• Immunological assays (radioimmunoassays) for antigenic characterization.

Main Results:

• Each retroviral isolate is unrelated by nucleic acid hybridization, possessing unique virion proteins.
• Major structural proteins and phosphoproteins differ significantly among isolates.
• Endogenous langur virus and Mason-Pfizer virus show close relatedness, supported by RNA genome homology.
• No single assay can detect all endogenous primate retroviridae due to interspecies antigenic determinants.

Conclusions:

• Primates possess a minimum of three distinct sets of genetically transmitted type C and type D retroviral genes.
• Primate retroviruses exhibit significant structural and antigenic diversity, reflecting distinct evolutionary paths.