Structural Organization and Strain Variation in the Genome of Varicella Zoster Virus
Abstract
The molecular organization of varicella zoster virus (VZV) DNA was examined using restriction endonuclease analysis and physical mapping techniques. Digestion of VZV DNA by EcoRI or BgIII results in four fragments which are present in 0.5 M amounts while the remaining restriction fragments are 1 M. Three terminal fragments were identified for both restriction enzymes using exonuclease III digestion. The results suggest that VZV DNA contains a terminal region which inverts inorientation. Electron microscopic examination shows that this terminal invertible segment is approximately 13.5 Mdal in size and consists of 4.3 Mdal of unique sequence DNA that is bound by 4.6 Mdal inverted repeat sequences. Thus VZV DNA can be divided into two covalently linked segments. The short segment is located at one terminus, can invert in orientation relative to the long segment and is bounded by inverted repeats. Examination of VZV DNA isolated from lesion fluids of patients with chickenpox or shingles or from virus grown in vitro all show strain specific differences in the migration of several restriction fragments which are stable in vitro. One difference appeared to map to the inverted repeats, because restriction fragments which contain these repeats increase or decrease in size by approximately the same amount relative to the size of the same fragments in other strains. Two additional variable regions were identified which mapped to the middle of the long unique segment. To characterize these strain variations, all the EcoRI restriction endonuclease fragments from four independent isolates of VZV were molecularly cloned. Recombinants containing variable fragments from each of the three regions in all four strains were initially identified by colony hybridization and were confirmed by Southern blots using specific probes.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 23, 1984
- Accession Number
- AD1010683
Entities
People
- Thomas A. Casey
Organizations
- Uniformed Services University of the Health Sciences