Symmetry, flexibility and permeability in the structure of yeast retrotransposon virus-like particles.
The virus-like particles (VLPs) of the yeast retrotransposon Ty are genetically, structurally and functionally analogous to retroviral nucleocapsids or cores. Like retroviral cores Ty-VLPs package and possibly promote the enzyme activities for reverse transcription and integration, as well as encapsulating the RNA that is the intermediate in retrotransposition. Here we show that Ty-VLPs assemble into symmetrical structures across a broad distribution of particle sizes. This spread of sizes violates the principle of quasi-equivalent packing. In addition, RNase accessibility experiments suggest that these particles form an open structure that does not protect the encapsulated RNA. These features distinguish Ty-VLPs from typical spherical viral capsids in both structure and function.
Burns
N R
NR
British Bio-technology Limited, Oxford, UK.
Saibil
H R
HR
White
N S
NS
Pardon
J F
JF
Timmins
P A
PA
Richardson
S M
SM
Richards
B M
BM
Adams
S E
SE
Kingsman
S M
SM
Kingsman
A J
AJ
D004251:DNA Transposable Elements; D005814:Genes, Viral; D007091:Image Processing, Computer-Assisted; D008854:Microscopy, Electron; D012331:RNA, Fungal / Q000235:genetics; D012190:Retroviridae / Q000235:genetics* / Q000648:ultrastructure; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D014158:Transcription, Genetic; D014461:Ultracentrifugation
D004251:DNA Transposable Elements; D012331:RNA, Fungal