Mouse APOBEC3 interferes with autocatalytic cleavage of murine leukemia virus Pr180gag-pol precursor and inhibits Pr65gag processing

English version

Autoři: Yoshiyuki Hakata ^aff001; Jun Li ^aff001; Takahiro Fujino ^aff003; Yuki Tanaka ^aff003; Rie Shimizu ^aff001; Masaaki Miyazawa ^aff001
Působiště autorů: Department of Immunology, Kindai University Faculty of Medicine, Osaka-Sayama, Osaka, Japan ^aff001; Ijunkai Medical Oncology, Endoscopy Clinic, Sakai-ku, Sakai, Osaka, Japan ^aff002; Division of Analytical Bio-Medicine, Advanced Research Support Center (ADRES), Ehime University, Shitsukawa, Toon, Ehime, Japan ^aff003; Kindai University Anti-Aging Center, Higashiosaka, Osaka, Japan ^aff004
Vyšlo v časopise: Mouse APOBEC3 interferes with autocatalytic cleavage of murine leukemia virus Pr180gag-pol precursor and inhibits Pr65gag processing. PLoS Pathog 15(12): e32767. doi:10.1371/journal.ppat.1008173
Kategorie: Research Article
doi: https://doi.org/10.1371/journal.ppat.1008173

Souhrn

Mouse APOBEC3 (mA3) inhibits murine leukemia virus (MuLV) replication by a deamination-independent mechanism in which the reverse transcription is considered the main target process. However, other steps in virus replication that can be targeted by mA3 have not been examined. We have investigated the possible effect of mA3 on MuLV protease-mediated processes and found that mA3 binds both mature viral protease and Pr180gag-pol precursor polyprotein. Using replication-competent MuLVs, we also show that mA3 inhibits the processing of Pr65 Gag precursor. Furthermore, we demonstrate that the autoprocessing of Pr180gag-pol is impeded by mA3, resulting in reduced production of mature viral protease. This reduction appears to link with the above inefficient Pr65gag processing in the presence of mA3. Two major isoforms of mA3, exon 5-containing and -lacking ones, equally exhibit this antiviral activity. Importantly, physiologically expressed levels of mA3 impedes both Pr180gag-pol autocatalysis and Pr65gag processing. This blockade is independent of the deaminase activity and requires the C-terminal region of mA3. These results suggest that the above impairment of Pr180gag-pol autoprocessing may significantly contribute to the deaminase-independent antiretroviral activity exerted by mA3.

Klíčová slova:

293T cells – Immunoblotting – Proteases – Transfection – Viral replication – Virions – Reverse transcription

Zdroje

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