Identification of a novel HIV-1 inhibitor targeting Vif-dependent degradation of human APOBEC3G protein.
APOBEC3G (A3G) is a cellular cytidine deaminase that restricts HIV-1 replication by inducing G-to-A hypermutation in viral DNA and by deamination-independent mechanisms. HIV-1 Vif binds to A3G, resulting in its degradation via the 26 S proteasome. Therefore, this interaction represents a potential therapeutic target. To identify compounds that inhibit interaction between A3G and HIV-1 Vif in a high throughput format, we developed a homogeneous time-resolved fluorescence resonance energy transfer assay. A 307,520 compound library from the NIH Molecular Libraries Small Molecule Repository was screened. Secondary screens to evaluate dose-response performance and off-target effects, cell-based assays to identify compounds that attenuate Vif-dependent degradation of A3G, and assays testing antiviral activity in peripheral blood mononuclear cells and T cells were employed. One compound, N.41, showed potent antiviral activity in A3G(+) but not in A3G(-) T cells and had an IC50 as low as 8.4 μM and a TC50 of >100 μM when tested against HIV-1Ba-L replication in peripheral blood mononuclear cells. N.41 inhibited the Vif-A3G interaction and increased cellular A3G levels and incorporation of A3G into virions, thereby attenuating virus infectivity in a Vif-dependent manner. N.41 activity was also species- and Vif-dependent. Preliminary structure-activity relationship studies suggest that a hydroxyl moiety located at a phenylamino group is critical for N.41 anti-HIV activity and identified N.41 analogs with better potency (IC50 as low as 4.2 μM). These findings identify a new lead compound that attenuates HIV replication by liberating A3G from Vif regulation and increasing its innate antiviral activity.
From the Departments of Cancer Immunology and AIDS and Departments of Pathology and.
Erez
E
Pery
Department of Biology, College of the Holy Cross, Worcester, Massachusetts 01610.
Ann
A
Sheehy
Southern Research Institute High Throughput Screening Center, Birmingham, Alabama 35205, and.
N Miranda
NM
Nebane
From the Departments of Cancer Immunology and AIDS and.
Andrew Jay
AJ
Brazier
From the Departments of Cancer Immunology and AIDS and.
Vikas
V
Misra
From the Departments of Cancer Immunology and AIDS and Departments of Pathology and.
Kottampatty S
KS
Rajendran
Cancer Biology, Dana Farber Cancer Institute and.
Sara J
SJ
Buhrlage
Southern Research Institute, Department of Infectious Disease Research, Frederick, Maryland 21701.
Marie K
MK
Mankowski
Southern Research Institute High Throughput Screening Center, Birmingham, Alabama 35205, and.
Lynn
L
Rasmussen
Southern Research Institute High Throughput Screening Center, Birmingham, Alabama 35205, and.
E Lucile
EL
White
Southern Research Institute, Department of Infectious Disease Research, Frederick, Maryland 21701.
Roger G
RG
Ptak
From the Departments of Cancer Immunology and AIDS and Neurology (Microbiology), Harvard Medical School, Boston, Massachusetts 02115, dana_gabuzda@dfci.harvard.edu.
Dana
D
Gabuzda
D000071480:APOBEC-3G Deaminase; D019380:Anti-HIV Agents / Q000737:chemistry / Q000494:pharmacology*; D001681:Biological Assay; D002460:Cell Line; D003564:Cytidine Deaminase / Q000235:genetics* / Q000378:metabolism; D031541:Fluorescence Resonance Energy Transfer; D005786:Gene Expression Regulation; D057809:HEK293 Cells; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D054884:Host-Pathogen Interactions; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000187:drug effects* / Q000378:metabolism / Q000821:virology; D061251:Primary Cell Culture; D046988:Proteasome Endopeptidase Complex / Q000187:drug effects / Q000378:metabolism; D059748:Proteolysis; D015398:Signal Transduction; D054852:Small Molecule Libraries / Q000737:chemistry / Q000494:pharmacology*; D013329:Structure-Activity Relationship; D013601:T-Lymphocytes / Q000187:drug effects* / Q000378:metabolism / Q000821:virology; D014779:Virus Replication / Q000187:drug effects; D054320:vif Gene Products, Human Immunodeficiency Virus / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism
D019380:Anti-HIV Agents; D054852:Small Molecule Libraries; D054320:vif Gene Products, Human Immunodeficiency Virus; C514847:vif protein, Human immunodeficiency virus 1; D046988:Proteasome Endopeptidase Complex; C061553:ATP dependent 26S protease; D000071480:APOBEC-3G Deaminase; C464924:APOBEC3G protein, human; D003564:Cytidine Deaminase
Antiviral Agent; Cytidine Deaminase; High Throughput Screening (HTS); Human Immunodeficiency Virus (HIV); Viral Protein; Virology