Betanodavirus B2 Is an RNA Interference Antagonist That Facilitates Intracellular Viral RNA Accumulation

Abstract

Volume 80, no. 1, p. [85][86][87][88][89][90][91][92][93][94] 2006. Page 86: We have recently realized that a protein sequence alignment comparing the B2 proteins of greasy grouper nervous necrosis virus (GGNNV) and flock house virus (FHV) is erroneous. The FHV sequence used in the article was not that of B2 but rather the frameshifted B1 protein. We have corrected the alignment using the FHV B2 sequence. Our conclusions regarding the low level of sequence similarity between the two proteins remain unchanged. The updated Fig. 1 and legend are shown below.FIG. 1. Amino acid sequences derived from previously published sequences (9, 16, 28) were aligned by using ClustalW, yielding sequence identities of 10.2 and 6.6% and similarities of 13.9 and 16.0% to NoV and FHV, respectively. 4909on May 9, 2018 by guest

Betanodavirus of Marine and Freshwater Fish: Distribution, Genomic Organization, Diagnosis and Control Measures

“…RNA2 forms a major ORF of capsid protein and consists of a highly conserved region and a variable region. In addition to this, RNA3, a sub genomic RNA (371 nt) has a 62 % G?C composition, containing an ORF encoding a peptide of 75 amino-acids corresponding to a hypothetical B2 protein which is a non-structural protein having a suppressor function for post-transcriptional gene silencing [19,34,61,110]. RNA3 is formed only in infected cells and is not packaged into the viral particles (not in chronically infected fish) [79,90,110] and is transcribed from the 3 0 end of RNA1.…”

Mechanisms controlling titer and expression of bidirectional lentiviral and gammaretroviral vectors

“…Importantly, incorporating a T-cell-specific murine CD3d promoter 34 into a bidirectional GV vector did not prevent expression of the antisense message and thus did not overcome titer restrictions possibly due to interaction of the internal promoter with enhancer sequences of the 5 0 promoter as described before (Supplementary Figure S2). 35 Consequently, we focused on the screening of RNAi suppressor proteins by cotransfecting either empty vector (ctrl), HIV Tat, 36 human foamy virus Tas, 37 tomato bushy stunt virus p19, 38 betanodamuravirus B2 39 or NovB2 21,40 expression plasmid to a normal transfection mixture for the production of GV bidirectional vectors. These experiments identified NovB2 as most potent in enhancing bidirectional vector titers in a dose-dependent manner.…”

Ingeniería genética vegetal para resistencia viral y vectores virales en genética reversa

“…Varios virus que infectan plantas codifican proteínas supresoras del silenciamiento entre las que se encuentran la proteína 2b de cucumovirus (Li and Ding, 2006), la proteína NS1 en la familia Orthomyxoviridae (Li et al, 2004), la proteína B2 en la familia Nodaviridae (Fenner et al, 2006), las proteínas P19 y P14 de los géneros tombusvirus y aureusvirus en la familia Tombusviridae (Voinnet et al, 1999;Merai et al, 2005), la proteína AC2 y sus homólogas en la familia Geminiviridae (Bisaro, 2006), y las proteínas ricas en cisteínas de los furoviurs, hordeiviruses, pecluviruses y tobravirus (Li and Ding, 2006) A modo de ejemplo se presenta en la figura 4 el mecanismo de acción de supresión del silenciamiento que se ha propuesto para la proteína HC-Pro de potyvirus. Estas proteínas supresoras no se producen hasta después que el virus ha comenzado a replicarse en las células infectadas, así que no causan supresión completa del mecanismo de defensa basado en ARN.…”