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Nuclear matrix protein Matrin 3 is a regulator of ZAP-mediated retroviral restriction.

Erazo A, Goff SP - Retrovirology (2015)

Bottom Line: This effect was shared with additional nuclear matrix proteins.Suppressing Matrin 3 powers a heightened and broader ZAP restriction of HIV-1 gene expression.This study suggests that this ZAP regulatory mechanism is shared with additional nuclear matrix proteins.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry and Molecular Biophysics, Howard Hughes Medical Institute, Columbia University, New York, NY, 10032, USA. ae2371@cumc.columbia.edu.

ABSTRACT

Background: Matrin 3 is a nuclear matrix protein involved in multiple nuclear processes. In HIV-1 infection, Matrin 3 serves as a Rev cofactor important for the cytoplasmic accumulation of HIV-1 transcripts. ZAP is a potent host restriction factor of multiple viruses including retroviruses HIV-1 and MoMuLV. In this study we sought to further characterize Matrin 3 functions in the regulation of HIV gene expression.

Results: Here we describe a function for Matrin 3 as a negative regulator of the ZAP-mediated restriction of retroviruses. Mass spectrometry analysis of Matrin 3-associated proteins uncovered interactions with proteins of the ZAP degradation complex, DDX17 and EXOSC3. Coimmunoprecipitation studies confirmed Matrin 3 associations with DDX17, EXOSC3 and ZAP, in a largely RNA-dependent manner, indicating that RNA is mediating the Matrin 3 interactions with these components of the ZAP degradation complex. Silencing Matrin 3 expression caused a remarkably enhanced ZAP-driven inhibition of HIV-1 and MoMuLV luciferase reporter viruses. This effect was shared with additional nuclear matrix proteins. ZAP targets multiply-spliced HIV-1 transcripts, but in the context of Matrin 3 suppression, this ZAP restriction was broadened to unspliced and multiply-spliced RNAs.

Conclusions: Here we reveal an unprecedented role for a nuclear matrix protein, Matrin 3, in the regulation of ZAP's antiretroviral activity. Suppressing Matrin 3 powers a heightened and broader ZAP restriction of HIV-1 gene expression. This study suggests that this ZAP regulatory mechanism is shared with additional nuclear matrix proteins.

No MeSH data available.


Related in: MedlinePlus

Matrin 3 interacts with components of the ZAP degradation machinery. a Matrin 3 interacts with DDX17. 293TrexhZAP2 cells were infected with HIV-luc (+) or mock infected (−) followed by doxycycline treatment at 200 ng/ml. Cells were then lysed in the presence (+) or absence (−) of RNAse A (50 µg/ml). Lysates were subjected to immunoprecipitation for endogenous Matrin 3 using rabbit α- Matrin 3 or α- control Ig. DDX17, GAPDH, b EXOSC3, or c myc-ZAP2 were detected with antibodies indicated.
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Fig1: Matrin 3 interacts with components of the ZAP degradation machinery. a Matrin 3 interacts with DDX17. 293TrexhZAP2 cells were infected with HIV-luc (+) or mock infected (−) followed by doxycycline treatment at 200 ng/ml. Cells were then lysed in the presence (+) or absence (−) of RNAse A (50 µg/ml). Lysates were subjected to immunoprecipitation for endogenous Matrin 3 using rabbit α- Matrin 3 or α- control Ig. DDX17, GAPDH, b EXOSC3, or c myc-ZAP2 were detected with antibodies indicated.

Mentions: To confirm that DDX17 and EXOSC3 interacted with Matrin 3, we tested for their coimmunoprecipitation with endogenous Matrin 3 in uninfected or infected 293TrexhZAP2 cells, a 293T cell line derivative in which doxycycline induces the expression of myc-tagged ZAP2, a functional human isoform truncated at the C-terminus. Additionally we tested for interaction with the central factor of this complex, ZAP. 293TrexhZAP2 cells were infected with a HIV-luc reporter virus and then treated with doxycycline at 2 h postinfection, and lysates were prepared 48 h after infection. Matrin 3 coimmunprecipitated with DDX17 with partial preference for the faster migrating p72 isoform, but not with the control GAPDH (Figure 1a). The association was partially disrupted by treatment with RNAse A. Matrin 3 also interacted with EXOSC3 (Figure 1b) and ZAP (Figure 1c) in a strongly RNA-dependent manner. Similar results were also obtained in TE671 cells (data not shown). This interaction of Matrin 3 with essential components of the RNA degradation machinery was observed in uninfected cells and with no apparent increase following HIV-luc infection. HIV-luc infection did not increase protein levels of DDX17, EXOSC3, or myc-ZAP2.Figure 1


Nuclear matrix protein Matrin 3 is a regulator of ZAP-mediated retroviral restriction.

Erazo A, Goff SP - Retrovirology (2015)

Matrin 3 interacts with components of the ZAP degradation machinery. a Matrin 3 interacts with DDX17. 293TrexhZAP2 cells were infected with HIV-luc (+) or mock infected (−) followed by doxycycline treatment at 200 ng/ml. Cells were then lysed in the presence (+) or absence (−) of RNAse A (50 µg/ml). Lysates were subjected to immunoprecipitation for endogenous Matrin 3 using rabbit α- Matrin 3 or α- control Ig. DDX17, GAPDH, b EXOSC3, or c myc-ZAP2 were detected with antibodies indicated.
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4487854&req=5

Fig1: Matrin 3 interacts with components of the ZAP degradation machinery. a Matrin 3 interacts with DDX17. 293TrexhZAP2 cells were infected with HIV-luc (+) or mock infected (−) followed by doxycycline treatment at 200 ng/ml. Cells were then lysed in the presence (+) or absence (−) of RNAse A (50 µg/ml). Lysates were subjected to immunoprecipitation for endogenous Matrin 3 using rabbit α- Matrin 3 or α- control Ig. DDX17, GAPDH, b EXOSC3, or c myc-ZAP2 were detected with antibodies indicated.
Mentions: To confirm that DDX17 and EXOSC3 interacted with Matrin 3, we tested for their coimmunoprecipitation with endogenous Matrin 3 in uninfected or infected 293TrexhZAP2 cells, a 293T cell line derivative in which doxycycline induces the expression of myc-tagged ZAP2, a functional human isoform truncated at the C-terminus. Additionally we tested for interaction with the central factor of this complex, ZAP. 293TrexhZAP2 cells were infected with a HIV-luc reporter virus and then treated with doxycycline at 2 h postinfection, and lysates were prepared 48 h after infection. Matrin 3 coimmunprecipitated with DDX17 with partial preference for the faster migrating p72 isoform, but not with the control GAPDH (Figure 1a). The association was partially disrupted by treatment with RNAse A. Matrin 3 also interacted with EXOSC3 (Figure 1b) and ZAP (Figure 1c) in a strongly RNA-dependent manner. Similar results were also obtained in TE671 cells (data not shown). This interaction of Matrin 3 with essential components of the RNA degradation machinery was observed in uninfected cells and with no apparent increase following HIV-luc infection. HIV-luc infection did not increase protein levels of DDX17, EXOSC3, or myc-ZAP2.Figure 1

Bottom Line: This effect was shared with additional nuclear matrix proteins.Suppressing Matrin 3 powers a heightened and broader ZAP restriction of HIV-1 gene expression.This study suggests that this ZAP regulatory mechanism is shared with additional nuclear matrix proteins.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry and Molecular Biophysics, Howard Hughes Medical Institute, Columbia University, New York, NY, 10032, USA. ae2371@cumc.columbia.edu.

ABSTRACT

Background: Matrin 3 is a nuclear matrix protein involved in multiple nuclear processes. In HIV-1 infection, Matrin 3 serves as a Rev cofactor important for the cytoplasmic accumulation of HIV-1 transcripts. ZAP is a potent host restriction factor of multiple viruses including retroviruses HIV-1 and MoMuLV. In this study we sought to further characterize Matrin 3 functions in the regulation of HIV gene expression.

Results: Here we describe a function for Matrin 3 as a negative regulator of the ZAP-mediated restriction of retroviruses. Mass spectrometry analysis of Matrin 3-associated proteins uncovered interactions with proteins of the ZAP degradation complex, DDX17 and EXOSC3. Coimmunoprecipitation studies confirmed Matrin 3 associations with DDX17, EXOSC3 and ZAP, in a largely RNA-dependent manner, indicating that RNA is mediating the Matrin 3 interactions with these components of the ZAP degradation complex. Silencing Matrin 3 expression caused a remarkably enhanced ZAP-driven inhibition of HIV-1 and MoMuLV luciferase reporter viruses. This effect was shared with additional nuclear matrix proteins. ZAP targets multiply-spliced HIV-1 transcripts, but in the context of Matrin 3 suppression, this ZAP restriction was broadened to unspliced and multiply-spliced RNAs.

Conclusions: Here we reveal an unprecedented role for a nuclear matrix protein, Matrin 3, in the regulation of ZAP's antiretroviral activity. Suppressing Matrin 3 powers a heightened and broader ZAP restriction of HIV-1 gene expression. This study suggests that this ZAP regulatory mechanism is shared with additional nuclear matrix proteins.

No MeSH data available.


Related in: MedlinePlus