Nonstructural proteins of Tobacco rattle virus which have a role in nematode-transmission: expression pattern and interaction with viral coat protein

Abstract

RNA 2 of Tobacco rattle virus isolate PpK20 encodes the viral coat protein (CP) and two nonstructural proteins of 40 kDa (' 40K protein ') and 32n8 kDa (' 32n8K '). The 40K protein is required for transmission of the virus by the vector nematode Paratrichodorus pachydermus whereas the 32n8K protein may be involved in transmission by other vector nematode species. An antiserum was raised against the 40K protein expressed in E. coli and used to study the expression and subcellular localization of this protein in infected Nicotiana benthamiana plants. The timecourse of the expression of the 40K protein in leaves and roots was similar to that of CP and both proteins were similarly distributed over the 1000 g pellet, 30 000 g pellet and 30 000 g supernatant fractions of leaf and root homogenates. Using the yeast two-hybrid system, a strong interaction between CP subunits was observed and weaker interactions between CP and the 32n8K protein and between CP and the 40K protein were detected. A deletion of the C-terminal 19 amino acids of CP interfered with the CP-40K interaction but not with CP-32n8K or CP-CP interactions, whereas a C-terminal deletion of 79 amino acids interfered with CP-40K and CP-32n8K interactions but not with the CP-CP interaction. As the C terminus of CP is known to be involved in nematodetransmission of tobraviruses, the data support the hypothesis that interactions between CP and RNA 2-encoded nonstructural proteins play a role in the transmission process.

Agrodrench: a novel and effective agroinoculation method for virus‐induced gene silencing in roots and diverse Solanaceous species

“…, 2001). TRV belongs to the genus Tobravirus and is mostly transmitted by nematodes through the soil (Matthews, 1991; Visser and Bol, 1999). TRV contains bipartite positive‐sense RNA genome (RNA1/RNA2; Matthews, 1991).…”

Efficient Virus-Induced Gene Silencing in Roots Using a Modified Tobacco Rattle Virus Vector

“…Its role and function in vector transmission is not fully elucidated (Vassilakos et al, 2001). As proposed for the potyviral helper component proteinase (HC-Pro; Blanc et al, 1997Blanc et al, , 1998, it is suggested that TRV-2b probably acts as a bridge linking the virion and vector mouthpart (Visser and Bol, 1999;Vellios et al, 2002b).…”

Molecular characterization of theTobacco rattle virusRNA2 genome isolated fromGladiolus

“…Previous studies of TRV showed that different isolates have very little sequence identity in the RNA2 region. The TRV RNA2 genome is 2-4 kb long and contains three or four open reading frames (ORFs) that encode viral coat proteins (CPs) and two or three ORFs related to the viral transmission process via nematodes [11,13]. In the RNA2 3′ nontranslated region (NTR), partial or complete tobravirus RNA1 3′ coding sequences were present in many of the reported sequences.…”