imported>Lcovelli at 13:56, 15 March 2010

2010-03-15T13:56:35Z

New page

{{Element
|genbank=[http://www.ncbi.nlm.nih.gov/entrez/viewer.fcgi?db=nucleotide&val=14575752 14575752]
|type=
|genus= Petuvirus
|subfamily= Class 4
|family= Caulimoviridae
|group= LTR retroelements

|description=''Petunia vein clearing virus'' (PVCV) is the type species of the ''Petuvirus'' genus of [[Caulimoviridae|''Caulimoviridae'']] plant virus family and represents the only member of this genus because of none new tentative species has been yet reported [''International Committee on the Taxonomy of Viruses'' (ICTV), [[Literature:100589|Fauquet ''et al''. 2005]]].
This pararetrovirus was first detected in ''Petunia x hybrida'' cv. Himmelsroeschen by electron microscopy ([[Literature:100623|Lesemann and Casper 1973]]) but has subsequently been reported in other Petunia species ([[Literature:100624|Richert-Pöggeler ''et al.'' 2002]]).
According to [[Literature:100596|Llorens ''et al'' 2009]], ''Petuvirus'' genus and consequently PVCV element, although falls more-or-less close to Class 1, constitutes an independent class (Class 4) in the phylogenetic study.

PVCV consists of unenveloped isometric particles of 43-46 nm in diameter (for more details also see [http://www.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/00.015.0.06.htm ICTVdb]) which genome, of circular dsDNA 7206 bp long, is organized into a large Open reading frame (ORF) (even if the first sequence deposited by [[Literature:63308|Richert-Pöggeler and Shepherd 1997]] showed two overlapping [http://www.ncbi.nlm.nih.gov/nuccore/9629729 ORFs]). The long encoded polyprotein of about 238 kD contains a putative movement protein typical of caulimoviruses, a putative integrase (INT) region similar to those coded by LTR retrotransposons, and the ''Ty3/Gypsy''-like coat (gag) and pol domains (protease, reverse transcriptase and RNaseH) ([[Literature:63308|Richert-Pöggeler and Shepherd 1997]]; [[Literature:29391|Harper ''et al.'' 2002]]). In contrast to other pararetrovirus which present a large consensus RNA-binding sequence associated to the putative COAT-''gag'' region -due to the presence of an additional cysteine at the -2 position (C-X-C-X2-C-X4-H-X4-C )-([[Literature:100605|Hull 1996]]; [[Literature:8054|Bouhida ''et al.'' 1993]]), PVCV contains the same cys-motif observed in the retroelement consensus RNA-binding sequence (C-X2-C-X4-H-X4-C) ([[Literature:63308|Richert-Pöggeler and Shepherd 1997]]). The INT protein of the retroviruses and retrotransposons is known to be the only protein required for the integration process, therefore the presence of a probable integrase function in the genome of PVCV suggests that it may exist both as a transmissible caulimovirus and as a retrotransposon potentially able to transpose in the Petunia genome ([[Literature:63308|Richert-Pöggeler and Shepherd 1997]]). In contrast to some other caulimoviruses, PVCV genome lacks both the transactivator (TAV) and aphid transmission functions (ATF). The absence of an insect acquisition gene may explain the limited hosts range in nature (it has been found only in ''Petunia'' spp. in which the virus is transmitted vertically and horizontally, [[Literature:63308|Richert-Pöggeler and Shepherd 1997]]; [[Literature:100624|Richert-Pöggeler ''et al.'' 2002]]; [[Literature:63307|Richert-Pöggeler ''et al.'' 2003]]).
|structure=PVCV2.png
|host=Petunia spp
|hostpic=Petunia_hybr.jpg
|literature=
|picowner=[http://commons.wikimedia.org/wiki/File:Petunia_hybr._03.JPG Wikimedia commons, courtesy of Kor!An author]
}}
[[Category:Element]]

Element:PVCV - Revision history

imported>Lcovelli at 13:56, 15 March 2010