[Non-structural protein 3]: Host membrane {Curator Inference}; Multi-pass membrane protein {Curator Inference}. [Non-structural protein 4]: Host membrane {Curator Inference}; Multi-pass membrane protein {Curator Inference}. [Non-structural protein 6]: Host membrane {Curator Inference}; Multi-pass membrane protein {Curator Inference}. [Non-structural protein 7]: Host cytoplasm, host perinuclear region {ECO:0000250}. Note=nsp7, nsp8, nsp9 and nsp10 are localized in cytoplasmic foci, largely perinuclear. Late in infection, they merge into confluent complexes (By similarity). {ECO:0000250}. [Non-structural protein 8]: Host cytoplasm, host perinuclear region {ECO:0000250}. Note=nsp7, nsp8, nsp9 and nsp10 are localized in cytoplasmic foci, largely perinuclear. Late in infection, they merge into confluent complexes (By similarity). {ECO:0000250}. [Non-structural protein 9]: Host cytoplasm, host perinuclear region {ECO:0000250}. Note=nsp7, nsp8, nsp9 and nsp10 are localized in cytoplasmic foci, largely perinuclear. Late in infection, they merge into confluent complexes (By similarity). {ECO:0000250}. [Non-structural protein 10]: Host cytoplasm, host perinuclear region {ECO:0000250}. Note=nsp7, nsp8, nsp9 and nsp10 are localized in cytoplasmic foci, largely perinuclear. Late in infection, they merge into confluent complexes (By similarity). {ECO:0000250}. [Helicase]: Host endoplasmic reticulum-Golgi intermediate compartment {Curator Inference}. Note=The helicase interacts with the N protein in membranous complexes and colocalizes with sites of synthesis of new viral RNA. {ECO:0000250}. [Uridylate-specific endoribonuclease]: Host cytoplasm, host perinuclear region {ECO:0000250}.
The host perinuclear region is the host cytoplasmic region just around the host nucleus. Note: This location is defined for viral proteins that appear in the perinuclear region of infected host cells
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. The papain-like proteinase 1 (PLP1) and papain-like proteinase 2 (PLP2) are responsible for the cleavages located at the N- terminus of the replicase polyprotein. In addition, PLP2 possesses a deubiquitinating/deISGylating activity and processes both 'Lys-48'- and 'Lys-63'-linked polyubiquitin chains from cellular substrates. PLP2 also antagonizes innate immune induction of type I interferon by blocking the nuclear translocation of host IRF-3 (By similarity). {By
Similarity}. [3C-like proteinase]: Responsible for the majority of cleavages as it cleaves the C-terminus of replicase polyprotein at 11 sites. Recognizes substrates containing the core sequence [ILMVF]-Q-|- [SGACN]. Inhibited by the substrate-analog Cbz-Val-Asn-Ser-Thr-Leu-Gln- CMK. Also contains an ADP-ribose-1''-phosphate (ADRP)-binding function (By similarity). {Sequence AnalysisPROSITE-ProRule:PRU00772}. The helicase which contains a zinc finger structure displays RNA and DNA duplex-unwinding activities with 5' to 3' polarity. ATPase activity is strongly stimulated by poly(U), poly(dT), poly(C), poly(dA), but not by poly(G) (By similarity). {By
Similarity}. The exoribonuclease acts on both ssRNA and dsRNA in a 3' to 5' direction. {By
Similarity}. Nsp7-nsp8 hexadecamer may possibly confer processivity to the polymerase, maybe by binding to dsRNA or by producing primers utilized by the latter. {By
Similarity}. Nsp9 is a ssRNA-binding protein. {By
Similarity}. [Uridylate-specific endoribonuclease]: Plays a role in viral transcription/replication and prevents the simultaneous activation of host cell dsRNA sensors, such as MDA5/IFIH1, OAS, and PKR (By similarity). 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) (By similarity). If not degraded, poly(U) RNA would hybridize with poly(A) RNA tails and activate host dsRNA sensors (By similarity). {By
Similarity|UniProtKB:P0C6X7}.
National and Kapodistrian University of Athens
Department of Biology
Biophysics & Bioinformatics Laboratory