Productive Replication and Evolution of HIV-1 in Ferret Cells

Fadel, Hind J.; Saenz, Dyana T.; Guevara, Rebekah B.; Messling, Véronika von; Peretz, Mary; Poeschla, Eric M.

doi:10.1128/jvi.06035-11

Cited by 9 publications

(6 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1, compare lanes 7 and 8). Interestingly, Rev expression stimulated VLP production Ͼ10-fold in cat (CRFK) and quail (QT35) cell types, a finding consistent with prior reports of significant Rev activity in nonhuman cell types other than those derived from rodents (43,(58)(59)(60). However, although hCRM1 exerted no effect on Rev activity in cat cells, VLP production in the avian cell line was enhanced a further ϳ10-fold when Rev and hCRM1 were expressed together ( Fig.…”

Section: Species-specific Regulation Of Hiv-1 Rev Activitysupporting

confidence: 89%

Cooperativity among Rev-Associated Nuclear Export Signals Regulates HIV-1 Gene Expression and Is a Determinant of Virus Species Tropism

Aligeti

Behrens

Pocock

et al. 2014

J Virol

View full text Add to dashboard Cite

Murine cells exhibit a profound block to HIV-1 virion production that was recently mapped to a species-specific structural attribute of the murine version of the chromosomal region maintenance 1 (mCRM1) nuclear export receptor and rescued by the expression of human CRM1 (hCRM1). In human cells, the HIV-1 Rev protein recruits hCRM1 to intron-containing viral mRNAs encoding the Rev response element (RRE), thereby facilitating viral late gene expression. Here we exploited murine 3T3 fibroblasts as a gain-of-function system to study hCRM1's species-specific role in regulating Rev's effector functions. We show that Rev is rapidly exported from the nucleus by mCRM1 despite only weak contributions to HIV-1's posttranscriptional stages. Indeed, Rev preferentially accumulates in the cytoplasm of murine 3T3 cells with or without hCRM1 expression, in contrast to human HeLa cells, where Rev exhibits striking en masse transitions between the nuclear and cytoplasmic compartments. Efforts to bias Rev's trafficking either into or out of the nucleus revealed that Rev encoding a second CRM1 binding domain (Rev-2xNES) or Rev-dependent viral gag-pol mRNAs bearing tandem RREs (GP-2xRRE), rescue virus particle production in murine cells even in the absence of hCRM1. Combined, these results suggest a model wherein Rev-associated nuclear export signals cooperate to regulate the number or quality of CRM1's interactions with viral Rev/RRE ribonucleoprotein complexes in the nucleus. This mechanism regulates CRM1-dependent viral gene expression and is a determinant of HIV-1's capacity to produce virions in nonhuman cell types. IMPORTANCECells derived from mice and other nonhuman species exhibit profound blocks to HIV-1 replication. Here we elucidate a block to HIV-1 gene expression attributable to the murine version of the CRM1 (mCRM1) nuclear export receptor. In human cells, hCRM1 regulates the nuclear export of viral intron-containing mRNAs through the activity of the viral Rev adapter protein that forms a multimeric complex on these mRNAs prior to recruiting hCRM1. We demonstrate that Rev-dependent gene expression is poor in murine cells despite the finding that, surprisingly, the bulk of Rev interacts efficiently with mCRM1 and is rapidly exported from the nucleus. Instead, we map the mCRM1 defect to the apparent inability of this factor to engage Rev multimers in the context of large viral Rev/RNA ribonucleoprotein complexes. These findings shed new light on HIV-1 gene regulation and could inform the development of novel antiviral strategies that target viral gene expression. T he nuclear pore complex (NPC) represents a key barrier to the replication of many viruses that infect eukaryotic cells (1-3). For retroviruses such as the primate lentivirus human immunodeficiency virus type 1 (HIV-1), the late, productive phases of the viral life cycle require efficient nuclear export of unspliced, and thus intron-containing, viral genomic RNAs (gRNAs) that (i) encode the group-specific antigen (Gag) and Gag-Pol polyproteins that form ...

show abstract

Section: Species-specific Regulation Of Hiv-1 Rev Activitysupporting

confidence: 89%

Cooperativity among Rev-Associated Nuclear Export Signals Regulates HIV-1 Gene Expression and Is a Determinant of Virus Species Tropism

Aligeti

Behrens

Pocock

et al. 2014

J Virol

View full text Add to dashboard Cite

show abstract

“…The domestic dog, cat, and ferret lack functional antiviral TRIM5alpha and TRIMCyp genes (29)(30)(31), leaving them without a version of the important postentry capsid-targeting systems that restrict retroviruses in the cells of numerous primates (32)(33)(34)(35); there is similarly no known carnivore equivalent to the mouse Fv1 gene (36). The cat does have an effective APOBEC3 protein repertoire, which is antagonized by feline immunodeficiency virus (FIV) Vif and feline foamy virus Bet (37)(38)(39)(40)(41).…”

mentioning

confidence: 99%

Feline Immunodeficiency Virus Envelope Glycoproteins Antagonize Tetherin through a Distinctive Mechanism That Requires Virion Incorporation

Morrison

Guevara

Marcano

et al. 2014

J Virol

Self Cite

View full text Add to dashboard Cite

BST2/tetherin inhibits the release of enveloped viruses from cells. Primate lentiviruses have evolved specific antagonists (Vpu, Nef, and Env). Here we characterized tetherin proteins of species representing both branches of the order Carnivora. Comparison of tiger and cat (Feliformia) to dog and ferret (Caniformia) genes demonstrated that the tiger and cat share a start codon mutation that truncated most of the tetherin cytoplasmic tail early in the Feliformia lineage (19 of 27 amino acids, including the dual tyrosine motif). Alpha interferon (IFN-␣) induced tetherin and blocked feline immunodeficiency virus (FIV) replication in lymphoid and nonlymphoid feline cells. Budding of bald FIV and HIV particles was blocked by carnivore tetherins. However, infectious FIV particles were resistant, and spreading FIV replication was uninhibited. Antagonism mapped to the envelope glycoprotein (Env), which rescued FIV from carnivore tetherin restriction when expressed in trans but, in contrast to known antagonists, did not rescue noncognate particles. Also unlike the primate lentiviral antagonists, but similar to the Ebola virus glycoprotein, FIV Env did not reduce intracellular or cell surface tetherin levels. Furthermore, FIV-enveloped FIV particles actually required tetherin for optimal release from cells. The results show that FIV Envs mediate a distinctive tetherin evasion. Well adapted to a phylogenetically ancient tetherin tail truncation in the Felidae, it requires functional virion incorporation of Env, and it shields the budding particle without downregulating plasma membrane tetherin. Moreover, FIV has evolved dependence on this protein: particles containing FIV Env need tetherin for optimal release from the cell, while Env ؊ particles do not. IMPORTANCEHIV-1 antagonizes the restriction factor tetherin with the accessory protein Vpu, while HIV-2 and the filovirus Ebola use their envelope (Env) glycoproteins for this purpose. It turns out that the FIV tetherin antagonist is also its Env protein, but the mechanism is distinctive. Unlike other tetherin antagonists, FIV Env cannot act in trans to rescue vpu-deficient HIV-1. It must be incorporated specifically into FIV virions to be active. Also unlike other retroviral antagonists, but similar to Ebola virus Env, it does not act by downregulating or degrading tetherin. FIV Env might exclude tetherin locally or direct assembly to tetherinnegative membrane domains. Other distinctive features are apparent, including evidence that this virus evolved an equilibrium in which tetherin is both restriction factor and cofactor, as FIV requires tetherin for optimal particle release.

show abstract

“…Human HEK 293T and HT1080 cells; Crandell feline kidney (CrFK) cells from Felis catus ; ferret alveolar epithelial cells (FtAEpC) and ferret kidney cells, each from Mustella putorius furo ( 69 ); owl-monkey kidney cells (OMK; ATCC CRL-1556); mouse 3T3 cells; and pteropid bat cell lines derived by Crameri et al ( 30 ) from Pteropus alecto kidney (paKiT01), brain (paBrH02), fetus (paFeSV40T), and lung (paLuT02) were maintained in Dulbecco’s modification of Eagle’s medium (DMEM) with 4.5 g/liter glucose; 10% fetal bovine serum; and 1× penicillin, streptomycin, and l -glutamine. Following transduction with Tsin IRESpuro HIV-1 vectors, P. alecto and CrFK cells were selected in 2 and 5 μg/ml puromycin, respectively.…”

Section: Methodsmentioning

confidence: 99%

A Potent Postentry Restriction to Primate Lentiviruses in a Yinpterochiropteran Bat

Morrison

Miller

Crameri

et al. 2020

mBio

Self Cite

View full text Add to dashboard Cite

Bats are primary reservoirs for multiple lethal human viruses, such as Ebola, Nipah, Hendra, rabies, severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome-related coronavirus (MERS-CoV), and, most recently, SARS-CoV-2. The innate immune systems of these immensely abundant, anciently diverged mammals remain insufficiently characterized. While bat genomes contain many endogenous retroviral elements indicative of past exogenous infections, little is known about restrictions to extant retroviruses. Here, we describe a major postentry restriction in cells of the yinpterochiropteran bat Pteropus alecto. Primate lentiviruses (HIV-1, SIVmac) were potently blocked at early life cycle steps, with up to 1,000-fold decreases in infectivity. The block was specific, because nonprimate lentiviruses such as equine infectious anemia virus and feline immunodeficiency virus were unimpaired, as were foamy retroviruses. Interspecies heterokaryons demonstrated a dominant block consistent with restriction of incoming viruses. Several features suggested potential TRIM5 (tripartite motif 5) or myxovirus resistance protein 2 (MX2) protein restriction, including postentry action, cyclosporine sensitivity, and reversal by capsid cyclophilin A (CypA) binding loop mutations. Viral nuclear import was significantly reduced, and this deficit was substantially rescued by cyclosporine treatment. However, saturation with HIV-1 virus-like particles did not relieve the restriction at all. P. alecto TRIM5 was inactive against HIV-1 although it blocked the gammaretrovirus N-tropic murine leukemia virus. Despite major divergence in a critical N-terminal motif required for human MX2 activity, P. alecto MX2 had anti-HIV activity. However, this did not quantitatively account for the restriction and was independent of and synergistic with an additional CypA-dependent restriction. These results reveal a novel, specific restriction to primate lentiviruses in the Pteropodidae and advance understanding of bat innate immunity. IMPORTANCE The COVID-19 pandemic suggests that bat innate immune systems are insufficiently characterized relative to the medical importance of these animals. Retroviruses, e.g., HIV-1, can be severe pathogens when they cross species barriers, and bat restrictions corresponding to retroviruses are comparatively unstudied. Here, we compared the abilities of retroviruses from three genera (Lentivirus, Gammaretrovirus, and Spumavirus) to infect cells of the large fruit-eating bat P. alecto and other mammals. We identified a major, specific postentry restriction to primate lentiviruses. HIV-1 and SIVmac are potently blocked at early life cycle steps, but nonprimate lentiviruses and foamy retroviruses are entirely unrestricted. Despite acting postentry and in a CypA-dependent manner with features reminiscent of antiretroviral factors from other mammals, this restriction was not saturable with virus-like particles and was independent of P. alecto TRIM5, TRIM21, TRIM22, TRIM34, and MX2. These results identify a novel restriction and highlight cyclophilin-capsid interactions as ancient species-specific determinants of retroviral infection.

show abstract

Productive Replication and Evolution of HIV-1 in Ferret Cells

Cited by 9 publications

References 72 publications

Cooperativity among Rev-Associated Nuclear Export Signals Regulates HIV-1 Gene Expression and Is a Determinant of Virus Species Tropism

Cooperativity among Rev-Associated Nuclear Export Signals Regulates HIV-1 Gene Expression and Is a Determinant of Virus Species Tropism

Feline Immunodeficiency Virus Envelope Glycoproteins Antagonize Tetherin through a Distinctive Mechanism That Requires Virion Incorporation

A Potent Postentry Restriction to Primate Lentiviruses in a Yinpterochiropteran Bat

Contact Info

Product

Resources

About