Delineation of sequences important for efficient packaging of feline immunodeficiency virus RNA.
We have used systematic deletion analysis of the 5' untranslated region (UTR) of the feline immunodeficiency virus (FIV) genome, both in the presence and absence of various amounts of gag, to define the cis-acting sequences responsible for efficient RNA packaging. Our analyses revealed that the primary FIV packaging signal consists of two essential core elements located within the first 90-120 bp of the 5'UTR and the first 90 bp of the gag gene. Interestingly, the region between the major splice donor (SD) and gag, including approximately 130-160 bp upstream of the SD, is dispensable for encapsidation. Finally, other determinants of packaging were found to be present in the viral LTR and/or within the 3' end of the viral genome. Taken together, our results suggest that the primary packaging determinants of FIV are multipartite and discontinuous, composed of two elements within the 5'UTR and gag gene.
Browning
Matthew T
MT
The University of Texas MD Anderson Cancer Center, Department of Veterinary Sciences, Bastrop, TX 78602, USA.
Mustafa
Farah
F
Department of Medical Microbiology, Faculty of Medicine and Health Sciences (FMHS), The United Arab Emirates University, PO Box 17666, Al Ain, United Arab Emirates.
Schmidt
Russell D
RD
The University of Texas MD Anderson Cancer Center, Department of Veterinary Sciences, Bastrop, TX 78602, USA.
Lew
Kathy A
KA
The University of Texas MD Anderson Cancer Center, Department of Veterinary Sciences, Bastrop, TX 78602, USA.
Rizvi
Tahir A
TA
Department of Medical Microbiology, Faculty of Medicine and Health Sciences (FMHS), The United Arab Emirates University, PO Box 17666, Al Ain, United Arab Emirates.|The University of Texas MD Anderson Cancer Center, Department of Veterinary Sciences, Bastrop, TX 78602, USA.
D020121:5' Untranslated Regions / Q000235:genetics; D000818:Animals; D019556:COS Cells; D002522:Chlorocebus aethiops; D017353:Gene Deletion; D015750:Genes, gag; D016089:Immunodeficiency Virus, Feline / Q000235:genetics / Q000502:physiology*; D012367:RNA, Viral; D020079:Terminal Repeat Sequences; D019065:Virus Assembly
D020121:5' Untranslated Regions; D012367:RNA, Viral