TY - JOUR
T1 - Splicing affects presentation of RNA dimerization signals in HIV-2 in vitro
AU - Lanchy, Jean Marc
AU - Szafran, Quenna N.
AU - Lodmell, J. Stephen
N1 - Funding Information:
plasmid pROD10) was provided by the EU Programme EVA/ MRC Centralized Facility for AIDS Reagents (NIBSC, UK; grant numbers QLK2-CT-1999-00609 and GP828102). All constructs were checked by DNA sequencing.
Funding Information:
We acknowledge Patrick Watson for critical reading of the manuscript and helpful suggestions. The pROD10 plasmids from Dr J.-M. Bechet and Dr A. M. L. Lever were obtained from the Centralised Facility for AIDS Reagents supported by EU Programme EVA (contract QLK2-CT-1999-00609) and the UK Medical Research Council. Q.N.S. was supported by NIH grant number P20RR-16455-03 from the BRIN Program of the National Center for Research Resources. This research is supported by the National Institutes of Health (grant number AI45388) to J.S.L.
PY - 2004
Y1 - 2004
N2 - During retroviral replication, full-length viral RNAs are encapsidated into new virus particles, while spliced RNAs are excluded. The Retroviridae are unique among viruses in that infectious viral particles contain a dimer of two identical genomic RNA strands. A variety of experimental data has suggested that dimerization and encapsidation of full-length viral RNAs are linked processes, although whether dimerization is a prerequisite for encapsidation, or conversely, dimerization follows encapsidation, has not been firmly established. If dimerization was the sole determinant for encapsidation, then spliced viral RNAs might be expected to display a reduced capacity for dimerization, resulting in their exclusion from the dimerization pool. Here, we studied the in vitro dimerization properties of unspliced and spliced HIV-2 RNA. We find that the rate and yield of dimerization of Nef, Rev and Tat spliced RNAs exceeded those of unspliced RNA. Although these data do not support a simple correlation between dimerization efficiency and the presence of introns, they establish that splicing affects the presentation of dimerization signal(s), which we corroborate with structure probing. This change in RNA conformation likely affects the RNA's suitability for packaging. Furthermore, the presence of upstream and downstream elements that affect the conformation of the packaging signal represents a potentially efficient viral strategy for correctly sorting spliced versus unspliced RNAs.
AB - During retroviral replication, full-length viral RNAs are encapsidated into new virus particles, while spliced RNAs are excluded. The Retroviridae are unique among viruses in that infectious viral particles contain a dimer of two identical genomic RNA strands. A variety of experimental data has suggested that dimerization and encapsidation of full-length viral RNAs are linked processes, although whether dimerization is a prerequisite for encapsidation, or conversely, dimerization follows encapsidation, has not been firmly established. If dimerization was the sole determinant for encapsidation, then spliced viral RNAs might be expected to display a reduced capacity for dimerization, resulting in their exclusion from the dimerization pool. Here, we studied the in vitro dimerization properties of unspliced and spliced HIV-2 RNA. We find that the rate and yield of dimerization of Nef, Rev and Tat spliced RNAs exceeded those of unspliced RNA. Although these data do not support a simple correlation between dimerization efficiency and the presence of introns, they establish that splicing affects the presentation of dimerization signal(s), which we corroborate with structure probing. This change in RNA conformation likely affects the RNA's suitability for packaging. Furthermore, the presence of upstream and downstream elements that affect the conformation of the packaging signal represents a potentially efficient viral strategy for correctly sorting spliced versus unspliced RNAs.
UR - http://www.scopus.com/inward/record.url?scp=4344562120&partnerID=8YFLogxK
U2 - 10.1093/nar/gkh800
DO - 10.1093/nar/gkh800
M3 - Article
C2 - 15333691
AN - SCOPUS:4344562120
SN - 0305-1048
VL - 32
SP - 4585
EP - 4595
JO - Nucleic Acids Research
JF - Nucleic Acids Research
IS - 15
ER -