View source for 8zfh


==Structure of the C-terminal domain of nsp4 from PDCOV==
<StructureSection load='8zfh' size='340' side='right'caption='[[8zfh]], [[Resolution|resolution]] 2.55&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8zfh]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Porcine_deltacoronavirus Porcine deltacoronavirus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8ZFH OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8ZFH FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.55&#8491;</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=8zfh FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8zfh OCA], [https://pdbe.org/8zfh PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8zfh RCSB], [https://www.ebi.ac.uk/pdbsum/8zfh PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8zfh ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A0A8E8PIM9_9NIDO A0A8E8PIM9_9NIDO] Forms a primer, NSP9-pU, which is utilized by the polymerase for the initiation of RNA chains. Interacts with ribosome signal recognition particle RNA (SRP). Together with NSP8, suppress protein integration into the cell membrane, thereby disrupting host immune defenses.[ARBA:ARBA00043928]  Plays a role in viral transcription/replication and prevents the simultaneous activation of host cell dsRNA sensors, such as MDA5/IFIH1, OAS, and PKR. Acts by degrading the 5'-polyuridines generated during replication of the poly(A) region of viral genomic and subgenomic RNAs. Catalyzes a two-step reaction in which a 2'3'-cyclic phosphate (2'3'-cP) is first generated by 2'-O transesterification, which is then hydrolyzed to a 3'-phosphate (3'-P). If not degraded, poly(U) RNA would hybridize with poly(A) RNA tails and activate host dsRNA sensors.[ARBA:ARBA00046192]  RNA-directed RNA polymerase that catalyzes the transcription of viral genomic and subgenomic RNAs. Acts in complex with nsp7 and nsp8 to transcribe both the minus and positive strands of genomic RNA. The kinase-like NiRAN domain of NSP12 attaches one or more nucleotides to the amino terminus of NSP9, forming a covalent RNA-protein intermediate that serves as transcription/replication primer. Subgenomic RNAs (sgRNAs) are formed by discontinuous transcription: The polymerase has the ability to pause at transcription-regulating sequences (TRS) and jump to the leader TRS, resulting in a major deletion. This creates a series of subgenomic RNAs that are replicated, transcribed and translated. In addition, Nsp12 is a subunit of the viral RNA capping enzyme that catalyzes the RNA guanylyltransferase reaction for genomic and sub-genomic RNAs. Subsequently, the NiRAN domain transfers RNA to GDP, and forms the core cap structure GpppA-RNA.[ARBA:ARBA00043918]  The replicase polyprotein of coronaviruses is a multifunctional protein: it contains the activities necessary for the transcription of negative stranded RNA, leader RNA, subgenomic mRNAs and progeny virion RNA as well as proteinases responsible for the cleavage of the polyprotein into functional products.[ARBA:ARBA00003368]
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Porcine deltacoronavirus]]
[[Category: Liang R]]
[[Category: Peng GQ]]
[[Category: Shi YJ]]
[[Category: Zhang D]]
[[Category: Zhang JT]]
[[Category: Zhang ZT]]