The Coronavirus Endoribonuclease Nsp 15 Interacts with Retinoblastoma 1 Tumor Suppressor Protein

نویسندگان

  • Kanchan Bhardwaj
  • Pinghua Liu
  • Julian L. Leibowitz
  • C. Cheng Kao
چکیده

19 Coronaviruses encode an endoribonuclease, Nsp15, which has a poorly defined role in 20 infection. Sequence analysis revealed a Retinoblastoma protein-binding motif (LXCXE/D) in the 21 majority of the Nsp15 of SARS coronavirus (SARS-CoV) and its orthologs in the alpha and beta 22 coronaviruses. Endoribonuclease activity of the SARS-CoV Nsp15 (sNsp15) was stimulated by 23 Retinoblastoma protein (pRb) in vitro and the two proteins can be co-immunoprecipitated from 24 cellular extracts. Mutations in the pRb-binding motif rendered sNsp15 to be differentially 25 modified by ubiquitin in cells and cytotoxicity was observed upon its expression. Expression of 26 the sNsp15 in cells resulted in an increased abundance of pRb in the cytoplasm, decreased 27 overall levels of pRb, increased proportion of cells in S phase of the cell cycle and enhanced 28 expression from a promoter normally repressed by pRb. The endoribonuclease activity of the 29 Mouse Hepatitis Virus A59 (MHV) Nsp15 was also increased by pRb in vitro and an MHV with 30 mutations in the LXCXE/D-motif, named vLC, exhibited smaller plaque diameter and reduced 31 viral titer by approximately one log. Overexpression of pRb delayed the viral protein production 32 by wild-type MHV but not by vLC. This study reveals that pRb and its interaction with Nsp15 33 can affect coronavirus infection and adds coronaviruses to a small but growing family of RNA 34 viruses that encode a protein to interact with pRb. 35 36 on Jauary 0, 2018 by gest http/jvi.asm .rg/ D ow nladed fom

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

The coronavirus endoribonuclease Nsp15 interacts with retinoblastoma tumor suppressor protein.

Coronaviruses encode an endoribonuclease, Nsp15, which has a poorly defined role in infection. Sequence analysis revealed a retinoblastoma protein-binding motif (LXCXE/D) in the majority of the Nsp15 of the severe acute respiratory syndrome coronavirus (SARS-CoV) and its orthologs in the alpha and beta coronaviruses. The endoribonuclease activity of the SARS-CoV Nsp15 (sNsp15) was stimulated by...

متن کامل

The severe acute respiratory syndrome coronavirus Nsp15 protein is an endoribonuclease that prefers manganese as a cofactor.

Nonstructural protein 15 (Nsp15) of the severe acute respiratory syndrome coronavirus (SARS-CoV) produced in Escherichia coli has endoribonuclease activity that preferentially cleaved 5' of uridylates of RNAs. Blocking either the 5' or 3' terminus did not affect cleavage. Double- and single-stranded RNAs were both substrates for Nsp15 but with different kinetics for cleavage. Mn(2+) at 2 to 10 ...

متن کامل

Bigh3 silencing increases retinoblastoma tumor growth in the murine SV40-TAg-Rb model

BIGH3, a secreted protein of the extracellular matrix interacts with collagen and integrins on the cell surface. BIGH3 can have opposing functions in cancer, acting either as tumor suppressor or promoter by enhancing tumor progression and angiogenesis. In the eye, BIGH3 is expressed in the cornea and the retinal pigment epithelium and could impact on the development of retinoblastoma, the most ...

متن کامل

The N-Terminal Domain of the Drosophila Retinoblastoma Protein Rbf1 Interacts with ORC and Associates with Chromatin in an E2F Independent Manner

BACKGROUND The retinoblastoma (Rb) tumor suppressor protein can function as a DNA replication inhibitor as well as a transcription factor. Regulation of DNA replication may occur through interaction of Rb with the origin recognition complex (ORC). PRINCIPAL FINDINGS We characterized the interaction of Drosophila Rb, Rbf1, with ORC. Using expression of proteins in Drosophila S2 cells, we found...

متن کامل

Site-directed mutagenesis of the Nidovirus replicative endoribonuclease NendoU exerts pleiotropic effects on the arterivirus life cycle.

The highly conserved NendoU replicative domain of nidoviruses (arteriviruses, coronaviruses, and roniviruses) belongs to a small protein family whose cellular branch is prototyped by XendoU, a Xenopus laevis endoribonuclease involved in nucleolar RNA processing. Recently, sequence-specific in vitro endoribonuclease activity was demonstrated for the NendoU-containing nonstructural protein (nsp) ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2012