Helper-component proteinase

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Helper-component proteinase
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EC no. 3.4.22.45
CAS no. 124566-20-7
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Helper-component proteinase (EC 3.4.22.45, HC-Pro) is an enzyme. [1] [2] This enzyme catalyses the following chemical reaction

Hydrolyses a Gly-Gly bond at its own C-terminus, commonly in the sequence -Tyr-Xaa-Val-Gly-Gly, in the processing of the potyviral polyprotein

This enzyme is present in plant RNA viruses of the Potyviridae family. HC-Pro is encoded by all potyviruses, but is absent in some members of the Ipomovirus genus. [3] HC-Pro is involved in virus transmission, virus polyprotein processing, and suppression of RNA silencing, an antiviral mechanism of plants. [4]

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References

  1. Kasschau KD, Carrington JC (May 1995). "Requirement for HC-Pro processing during genome amplification of tobacco etch potyvirus". Virology. 209 (1): 268–73. doi: 10.1006/viro.1995.1254 . PMID   7747479.
  2. Verchot, J. (1998). "Potyvirus helper component proteinase". In Barrett, A.J.; Rawlings, N.D.; Woessner, J.F. (eds.). Handbook of Proteolytic Enzymes. London: Handbook of Proteolytic Enzymes. pp. 677–679.
  3. Pasin, Fabio; Daròs, José-Antonio; Tzanetakis, Ioannis E (2022). "Proteome expansion in the Potyviridae evolutionary radiation". FEMS Microbiology Reviews. 46 (4): fuac011. doi:10.1093/femsre/fuac011. ISSN   1574-6976. PMC   9249622 . PMID   35195244.
  4. Valli, Adrián A.; Gallo, Araiz; Rodamilans, Bernardo; López-Moya, Juan José; García, Juan Antonio (March 2018). "The HCPro from the Potyviridae family: an enviable multitasking Helper Component that every virus would like to have: The HCPro from the Potyviridae family". Molecular Plant Pathology. 19 (3): 744–763. doi:10.1111/mpp.12553. PMC   6638112 . PMID   28371183.