scholarly journals Backbone chemical shift spectral assignments of SARS coronavirus-2 non-structural protein nsp9

2021 ◽  
Author(s):  
Erika F. Dudás ◽  
Rita Puglisi ◽  
Sophie Marianne Korn ◽  
Caterina Alfano ◽  
Maria Laura Bellone ◽  
...  
Keyword(s):  
Chemical Shift ◽  
Rna Synthesis ◽  
Rna Binding ◽  
Analytical Ultracentrifugation ◽  
Structural Protein ◽  
Lead Compounds ◽  
Starting Point ◽  
Backbone Chemical Shift ◽  
Complete Assignment ◽  
Backbone Atoms

AbstractAs part of an International consortium aiming at the characterization by NMR of the proteins of the SARS-CoV-2 virus, we have obtained the virtually complete assignment of the backbone atoms of the non-structural protein nsp9. This small (12 kDa) protein is encoded by ORF1a, binds to RNA and seems to be essential for viral RNA synthesis. The crystal structures of the SARS-CoV-2 protein and other homologues suggest that the protein is dimeric as also confirmed by analytical ultracentrifugation and dynamic light scattering. Our data constitute the prerequisite for further NMR-based characterization, and provide the starting point for the identification of small molecule lead compounds that could interfere with RNA binding and prevent viral replication.

scholarly journals 1H, 13C, and 15N backbone chemical shift assignments of the C-terminal dimerization domain of SARS-CoV-2 nucleocapsid protein

2020 ◽  
Author(s):  
Sophie M. Korn ◽  
Roderick Lambertz ◽  
Boris Fürtig ◽  
Martin Hengesbach ◽  
Frank Löhr ◽  
...  
Keyword(s):  
Chemical Shift ◽  
Nucleocapsid Protein ◽  
Rna Binding ◽  
Drug Binding ◽  
Chemical Shift Assignments ◽  
Binding Studies ◽  
Dimerization Domain ◽  
N Protein ◽  
Intrinsically Disordered ◽  
Backbone Chemical Shift

AbstractThe current outbreak of the highly infectious COVID-19 respiratory disease is caused by the novel coronavirus SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2). To fight the pandemic, the search for promising viral drug targets has become a cross-border common goal of the international biomedical research community. Within the international Covid19-NMR consortium, scientists support drug development against SARS-CoV-2 by providing publicly available NMR data on viral proteins and RNAs. The coronavirus nucleocapsid protein (N protein) is an RNA-binding protein involved in viral transcription and replication. Its primary function is the packaging of the viral RNA genome. The highly conserved architecture of the coronavirus N protein consists of an N-terminal RNA-binding domain (NTD), followed by an intrinsically disordered Serine/Arginine (SR)-rich linker and a C-terminal dimerization domain (CTD). Besides its involvement in oligomerization, the CTD of the N protein (N-CTD) is also able to bind to nucleic acids by itself, independent of the NTD. Here, we report the near-complete NMR backbone chemical shift assignments of the SARS-CoV-2 N-CTD to provide the basis for downstream applications, in particular site-resolved drug binding studies.

scholarly journals 1H, 13C, and 15N backbone chemical-shift assignments of SARS-CoV-2 non-structural protein 1 (leader protein)

2021 ◽  
Author(s):  
Ying Wang ◽  
John Kirkpatrick ◽  
Susanne zur Lage ◽  
Sophie M. Korn ◽  
Konstantin Neißner ◽  
...  
Keyword(s):  
Chemical Shift ◽  
Open Reading Frames ◽  
Viral Rna ◽  
Backbone Dynamics ◽  
Chemical Shift Assignments ◽  
Immune Functions ◽  
Structural Protein ◽  
Health Crisis ◽  
Backbone Chemical Shift ◽  
Reading Frames

AbstractThe current COVID-19 pandemic caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has become a worldwide health crisis, necessitating coordinated scientific research and urgent identification of new drug targets for treatment of COVID-19 lung disease. The covid19-nmr consortium seeks to support drug development by providing publicly accessible NMR data on the viral RNA elements and proteins. The SARS-CoV-2 genome comprises a single RNA of about 30 kb in length, in which 14 open reading frames (ORFs) have been annotated, and encodes approximately 30 proteins. The first two-thirds of the SARS-CoV-2 genome is made up of two large overlapping open-reading-frames (ORF1a and ORF1b) encoding a replicase polyprotein, which is subsequently cleaved to yield 16 so-called non-structural proteins. The non-structural protein 1 (Nsp1), which is considered to be a major virulence factor, suppresses host immune functions by associating with host ribosomal complexes at the very end of its C-terminus. Furthermore, Nsp1 facilitates initiation of viral RNA translation via an interaction of its N-terminal domain with the 5′ untranslated region (UTR) of the viral RNA. Here, we report the near-complete backbone chemical-shift assignments of full-length SARS-CoV-2 Nsp1 (19.8 kDa), which reveal the domain organization, secondary structure and backbone dynamics of Nsp1, and which will be of value to further NMR-based investigations of both the biochemical and physiological functions of Nsp1.

scholarly journals 1H, 13C, and 15N backbone chemical shift assignments of the nucleic acid-binding domain of SARS-CoV-2 non-structural protein 3e

2020 ◽  
Vol 14 (2) ◽  
pp. 329-333
Author(s):  
Sophie M. Korn ◽  
Karthikeyan Dhamotharan ◽  
Boris Fürtig ◽  
Martin Hengesbach ◽  
Frank Löhr ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Chemical Shift ◽  
Binding Domain ◽  
Chemical Shift Assignments ◽  
Nucleic Acid Binding ◽  
Structural Protein ◽  
Backbone Chemical Shift

scholarly journals Selective Replication of Coronavirus Genomes That Express Nucleocapsid Protein

2005 ◽  
Vol 79 (11) ◽  
pp. 6620-6630 ◽  
Author(s):  
Barbara Schelle ◽  
Nadja Karl ◽  
Burkhard Ludewig ◽  
Stuart G. Siddell ◽  
Volker Thiel
Keyword(s):  
Nucleocapsid Protein ◽  
Rna Synthesis ◽  
Rna Binding ◽  
N Gene ◽  
Reverse Genetic ◽  
Structural Protein ◽  
N Protein ◽  
Human Coronavirus 229E ◽  
Reverse Genetic Approach

ABSTRACT The coronavirus nucleocapsid (N) protein is a structural protein that forms a ribonucleoprotein complex with genomic RNA. In addition to its structural role, it has been described as an RNA-binding protein that might be involved in coronavirus RNA synthesis. Here, we report a reverse genetic approach to elucidate the role of N in coronavirus replication and transcription. We found that human coronavirus 229E (HCoV-229E) vector RNAs that lack the N gene were greatly impaired in their ability to replicate, whereas the transcription of subgenomic mRNA from these vectors was easily detectable. In contrast, vector RNAs encoding a functional N protein were able to carry out both replication and transcription. Furthermore, modification of the transcription signal required for the synthesis of N protein mRNAs in the HCoV-229E genome resulted in the selective replication of genomes that are able to express the N protein. This genetic evidence leads us to conclude that at least one coronavirus structural protein, the N protein, is involved in coronavirus replication.

Toho-1 β-lactamase: backbone chemical shift assignments and changes in dynamics upon binding with avibactam

2021 ◽  
Author(s):  
Varun V. Sakhrani ◽  
Rittik K. Ghosh ◽  
Eduardo Hilario ◽  
Kevin L. Weiss ◽  
Leighton Coates ◽  
...  
Keyword(s):  
Chemical Shift ◽  
Chemical Shift Assignments ◽  
Backbone Chemical Shift

scholarly journals Mutations in the nuclear localization signal of nsP2 influencing RNA synthesis, protein expression and cytotoxicity of Semliki Forest virus

2008 ◽  
Vol 89 (3) ◽  
pp. 676-686 ◽  
Author(s):  
Kristi Tamm ◽  
Andres Merits ◽  
Inga Sarand
Keyword(s):  
Nuclear Localization ◽  
Nuclear Localization Signal ◽  
Rna Synthesis ◽  
Semliki Forest Virus ◽  
Temperature Sensitive ◽  
Structural Protein ◽  
Arginine Residues ◽  
Localization Signal ◽  
Infected Cells ◽  
Replicase Complex

The cytotoxicity of Semliki Forest virus (SFV) infection is caused partly by the non-structural protein nsP2, an essential component of the SFV replicase complex. Due to the presence of a nuclear localization signal (NLS), nsP2 also localizes in the nucleus of infected cells. The present study analysed recombinant SFV replicons and genomes with various deletions or substitutions in the NLS, or with a proline-to-glycine mutation at position 718 of nsP2 (P718G). Deletion of one or two arginine residues from the NLS or substitution of two of the arginines with aspartic acid resulted in a virus with a temperature-sensitive phenotype, and substitution of all three arginines was lethal. Thus, most of the introduced mutations severely affected nsP2 functioning in viral replication; in addition, they inhibited the ability of SFV to induce translational shut-off and kill infected cells. SFV replicons with a P718G mutation or replacement of the NLS residues 648RRR650 with RDD were found to be the least cytotoxic. Corresponding replicons expressed non-structural proteins at normal levels, but had severely reduced genomic RNA synthesis and were virtually unable to replicate and transcribe co-electroporated helper RNA. The non-cytotoxic phenotype was maintained in SFV full-length genomes harbouring the corresponding mutations; however, during a single cycle of cell culture, these were converted to a cytotoxic phenotype, probably due to the accumulation of compensatory mutations.

scholarly journals Distinct Poly(rC) Binding Protein KH Domain Determinants for Poliovirus Translation Initiation and Viral RNA Replication

2002 ◽  
Vol 76 (23) ◽  
pp. 12008-12022 ◽  
Author(s):  
Brandon L. Walter ◽  
Todd B. Parsley ◽  
Ellie Ehrenfeld ◽  
Bert L. Semler
Keyword(s):  
Translation Initiation ◽  
Rna Synthesis ◽  
Rna Binding ◽  
Binding Protein ◽  
Rna Replication ◽  
Viral Rna ◽  
Host Protein ◽  
Loop Structure ◽  
Stem Loop ◽  
Stem Loop Structure

ABSTRACT The limited coding capacity of picornavirus genomic RNAs necessitates utilization of host cell factors in the completion of an infectious cycle. One host protein that plays a role in both translation initiation and viral RNA synthesis is poly(rC) binding protein 2 (PCBP2). For picornavirus RNAs containing type I internal ribosome entry site (IRES) elements, PCBP2 binds the major stem-loop structure (stem-loop IV) in the IRES and is essential for translation initiation. Additionally, the binding of PCBP2 to the 5′-terminal stem-loop structure (stem-loop I or cloverleaf) in concert with viral protein 3CD is required for initiation of RNA synthesis directed by poliovirus replication complexes. PCBP1, a highly homologous isoform of PCBP2, binds to poliovirus stem-loop I with an affinity similar to that of PCBP2; however, PCBP1 has reduced affinity for stem-loop IV. Using a dicistronic poliovirus RNA, we were able to functionally uncouple translation and RNA replication in PCBP-depleted extracts. Our results demonstrate that PCBP1 rescues RNA replication but is not able to rescue translation initiation. We have also generated mutated versions of PCBP2 containing site-directed lesions in each of the three RNA-binding domains. Specific defects in RNA binding to either stem-loop I and/or stem-loop IV suggest that these domains may have differential functions in translation and RNA replication. These predictions were confirmed in functional assays that allow separation of RNA replication activities from translation. Our data have implications for differential picornavirus template utilization during viral translation and RNA replication and suggest that specific PCBP2 domains may have distinct roles in these activities.

Sign in / Sign up

Export Citation Format

Share Document