Pospiviroidae

In this article, we will explore the fascinating world of Pospiviroidae, a topic that has captivated the attention of millions of people around the world. Pospiviroidae has been the subject of multiple studies and research over the years, and its impact on modern society is undeniable. Since its discovery, Pospiviroidae has generated endless debates and controversies, awakening unprecedented interest in various areas of knowledge. Throughout the next lines, we will delve into the most relevant details about Pospiviroidae, exploring its history, its influence today and the future perspectives it offers. It doesn't matter if you are an expert on the subject or just curious, this article will give you an enriching and complete look at Pospiviroidae.

Pospiviroidae
Virus classification Edit this classification
(unranked): Viroid
Family: Pospiviroidae
Genera

The Pospiviroidae are a incertae sedis family of ssRNA viroids with 5 genera and 39 species, including the first viroid to be discovered, PSTVd, which is part of genus Pospiviroid. Their secondary structure is key to their biological activity. The classification of this family is based on differences in the conserved central region sequence. Pospiviroidae replication occurs in an asymmetric fashion via host cell RNA polymerase, RNase, and RNA ligase. Its hosts are plants, specifically dicotyledons and some monocotyledons.

Genome

Members of the family Pospiviroidae have circular ssRNA of 246–375 nt. They assume rod-like or quasi-rod-like conformations containing a central conserved region (CCR) and a terminal conserved hairpin (TCH) or a terminal conserved region (TCR). The genome of viroids does not encode any proteins.

Replication

Its replication is nuclear and mediated by DNA-dependent RNA polymerase II, which is redirected to use RNA templates through an asymmetric RNA–RNA rolling-circle mechanism. (+) polarity circRNA molecules (by convention the most abundant strand in vivo) are repeatedly transcribed into oligomeric complementary (−) RNAs. Such intermediates serve as templates for generating oligomeric (+) RNAs that are cleaved by a host enzyme of the RNase III class. The termini of the resulting linear monomers are ligated by the host DNA ligase 1 to generate the mature circular viroid RNA.

Taxonomy

Apscaviroid

Cocadviroid

Coleviroid

Hostuviroid

Pospiviroid

References

  1. ^ Di Serio, F; Owens, RA; Li, SF; Matoušek, J; Pallás, V; Randles, JW; Sano, T; Verhoeven, JTJ; Vidalakis, G; Flores, R; ICTV Report Consortium (17 December 2020). "ICTV Virus Taxonomy Profile: Pospiviroidae". The Journal of General Virology. 102 (2). doi:10.1099/jgv.0.001543. PMC 8116940. PMID 33331814.
  2. ^ "Virus Taxonomy: 2022 Release". International Committee on Taxonomy of Viruses (ICTV). March 2023. Retrieved 20 August 2023.
  3. ^ "ICTV Report Pospiviroidae".
  4. ^ a b Francesco Di Serio, Robert A. Owens, Shi-Fang Li, Matoušek J, Pallás V, John W. Randles, Sano T, Jacobus Th. J. Verhoeven, Vidalakis G, Flores R (2020). "ICTV Virus Taxonomy Profile: Pospiviroidae". J Gen Virol. 102 (2): 001543. doi:10.1099/jgv.0.001543. PMC 8116940. PMID 33331814.

External links