A DEAD box protein facilitates HIV-1 replication as a cellular co-factor of Rev.
HIV-1 Rev escorts unspliced viral mRNAs out of the nucleus of infected cells, which allows formation of infectious HIV-1 virions. We have identified a putative DEAD box (Asp-Glu-Ala-Asp) RNA helicase, DDX1, as a cellular co-factor of Rev, through yeast and mammalian two-hybrid systems using the N-terminal motif of Rev as "bait". DDX1 is not a functional homolog of HIV-1 Rev, but down-regulation of DDX1 resulted in an alternative splicing pattern of Rev-responsive element (RRE)-containing mRNA, and attenuation of Gag p24 antigen production from HLfb rev- cells rescued by exogenous Rev. Co-transfection of a DDX1 expression vector with HIV-1 significantly increased viral production. DDX1 binding to Rev, as well as to the RRE, strongly suggest that DDX1 affects Rev function through the Rev-RRE axis. Moreover, down-regulation of DDX1 altered the steady state subcellular distribution of Rev, from nuclear/nucleolar to cytoplasmic dominance. These findings indicate that DDX1 is a critical cellular co-factor for Rev function, which maintains the proper subcellular distribution of this lentiviral regulatory protein. Therefore, alterations in DDX1-Rev interactions could induce HIV-1 persistence and targeting DDX1 may lead to rationally designed and novel anti-HIV-1 strategies and therapeutics.
Fang
Jianhua
J
Division of Infectious Diseases and Environmental Medicine, Department of Medicine, The Dorrance H. Hamilton Laboratories, Center for Human Virology and Biodefense, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA.
Kubota
Satoshi
S
Yang
Bin
B
Zhou
Naiming
N
Zhang
Hui
H
Godbout
Roseline
R
Pomerantz
Roger J
RJ
D000818:Animals; D002460:Cell Line; D002522:Chlorocebus aethiops; D053487:DEAD-box RNA Helicases; D015967:Gene Expression Regulation, Viral; D015694:Gene Products, rev / Q000378:metabolism*; D015752:Genes, env / Q000502:physiology; D016655:HIV Core Protein p24 / Q000096:biosynthesis; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D011485:Protein Binding; D025941:Protein Interaction Mapping; D020365:RNA Helicases / Q000378:metabolism*; D012326:RNA Splicing; D012367:RNA, Viral / Q000378:metabolism; D020798:Two-Hybrid System Techniques; D014779:Virus Replication / Q000235:genetics; D054321:rev Gene Products, Human Immunodeficiency Virus
D015694:Gene Products, rev; D016655:HIV Core Protein p24; D012367:RNA, Viral; D054321:rev Gene Products, Human Immunodeficiency Virus; C086252:DDX1 protein, human; D053487:DEAD-box RNA Helicases; D020365:RNA Helicases