Aphid Acquisition and Cellular Transport of Potato leafroll virus-like Particles Lacking P5 Readthrough Protein

Lepidopteran cells (Spodoptera frugiperda) produced isometric virus-like particles (VLP) when infected with a recombinant baculovirus Ac61 that contained the Potato leafroll virus (PLRV) coat protein gene modified with an N-terminal histidine tag (P3-6H). Cells infected with AcFL, a recombinant baculovirus that expressed cDNA copies of the PLRV genome RNA, did not produce virus-like particles (VLP). In cell lines doubly infected with Ac61 and AcFL, VLP were formed that contained PLRV-RNA packaged in P3-6H coat protein (FL). Both the P3-6H and the FL particles were morphologically indistinguishable from particles of PLRV despite the fact that they lacked the P5 readthrough protein present in wild-type PLRV. When aphids (Myzus persicae) were fed on, or injected with, purified PLRV, or VLP of either type (FL or P3-6H) and examined by electron microscopy, no differences were observed among treatments for particle endocytosis, transcellular transport, or exocytosis at the aphid midgut or accessory salivary glands. Particles were observed in the salivary canals and in the salivary duct leading out of the aphid. These results suggest that P5 readthrough protein of PLRV may not be essential for cellular transport of virus through aphid vectors.

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Virus-like particles of potato leafroll virus as potential carrier system for nucleic acids.

Acta Biochimica Polonica ◽

10.18388/abp.2005_3433 ◽

2005 ◽

Vol 52 (3) ◽

pp. 699-702 ◽

Cited By ~ 3

Author(s):

Elzbieta Sułuja ◽

Ludmiła Strokowskaja ◽

Włodzimierz Zagórski-Ostoja ◽

Andrzej Pałucha

Keyword(s):

Coat Protein ◽

Nucleic Acids ◽

Coat Protein Gene ◽

Insect Cells ◽

Protein Gene ◽

Recombinant Baculovirus ◽

Potato Leafroll Virus ◽

Rnase A ◽

Virus Like Particles ◽

Leafroll Virus

Potato leafroll virus is a member of the polerovirus genus. The isometric virion is formed by a coat protein encapsidating single-stranded, positive-sense, mono-partite genomic RNA with covalently attached viral protein at the 5' end. The coat protein of the virus exists in two forms: i) a 23 kDa protein, the product of the coat protein gene, and ii) a 78 kDa protein, the product of the coat protein gene and an additional open reading frame expressed by read-through of the coat protein gene stop codon. The aim of this work was the expression of potato leafroll virus coat protein-based proteins that would be able to assemble into virus-like particles in insect cells. These modified particles were tested for their ability to encapsidate nucleic acids. Two types of N-terminally His-tagged coat protein constructs were used for the expression in insect cells: one, encoding a 23 kDa protein with the C-terminal amino-acid sequence corresponding to the wild type coat protein and the second with additional clathrin binding domain at the C-terminus. The expression of these two proteins by a recombinant baculovirus was characterized by Western immunoblotting with antibodies directed against potato leafroll virus. The protection or putative encapsidation of nucleic acids by these two coat protein derivatives was shown by DNase I and RNase A protection assays.

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The passage of Potato leafroll virus through Myzus persicae gut membrane regulates transmission efficiency

Journal of General Virology ◽

10.1099/0022-1317-82-1-17 ◽

2001 ◽

Vol 82 (1) ◽

pp. 17-23 ◽

Cited By ~ 31

Author(s):

J. Rouzé-Jouan ◽

L. Terradot ◽

F. Pasquer ◽

S. Tanguy ◽

D. Giblot Ducray-Bourdin

Keyword(s):

Amino Acid ◽

Coat Protein ◽

Myzus Persicae ◽

Virus Transmission ◽

Transmission Efficiency ◽

Potato Leafroll Virus ◽

Transmission Process ◽

Leafroll Virus ◽

Readthrough Protein

Potato leafroll virus (PLRV) is transmitted by aphids in a persistent manner. Although virus circulation within the aphid leading to transmission has been well characterized, the mechanisms involved in virus recognition at aphid membranes are still poorly understood. One isolate in our collection (PLRV-14.2) has been shown to be non- or only poorly transmitted by some clones of aphids belonging to the Myzus persicae complex. To determine where the transmission process was blocked within the aphid, three virus transmission procedures were used. PLRV-14.2 could not be transmitted, or was only very poorly transmitted, after acquisition from infected plants or from purified preparations. In contrast, it could be transmitted with more than 70% efficiency when microinjected. Therefore, it is concluded that the gut membrane was a barrier regulating passage of PLRV particles from the gut lumen into the haemocoel of M. persicae. Comparison of coat protein (CP) and readthrough protein (RTP) sequences between poorly and readily transmissible isolates showed that PLRV-14.2 differed from other PLRV isolates by amino acid changes in both of these proteins. It is hypothesized that at least some of the changes found in CP and/or RTP reduced virus recognition by aphid gut receptors, resulting in reduced acquisition and subsequent transmission of PLRV-14.2.

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A Surface Loop of the Potato Leafroll Virus Coat Protein Is Involved in Virion Assembly, Systemic Movement, and Aphid Transmission

Journal of Virology ◽

10.1128/jvi.79.2.1207-1214.2005 ◽

2005 ◽

Vol 79 (2) ◽

pp. 1207-1214 ◽

Cited By ~ 44

Author(s):

Lawrence Lee ◽

Igor B. Kaplan ◽

Daniel R. Ripoll ◽

Delin Liang ◽

Peter Palukaitis ◽

...

Keyword(s):

Amino Acids ◽

Coat Protein ◽

Virus Assembly ◽

Systemic Infection ◽

Aphid Transmission ◽

Potato Leafroll Virus ◽

Wild Type Virus ◽

Virion Assembly ◽

Aphid Vectors ◽

Leafroll Virus

ABSTRACT Two acidic domains of the Potato leafroll virus (PLRV) coat protein, separated by 55 amino acids and predicted to be adjacent surface features on the virion, were the focus of a mutational analysis. Eleven site-directed mutants were generated from a cloned infectious cDNA of PLRV and delivered to plants by Agrobacterium-mediated mechanical inoculation. Alanine substitutions of any of the three amino acids of the sequence EWH (amino acids 170 to 172) or of D177 disrupted the ability of the coat protein to assemble stable particles and the ability of the viral RNA to move systemically in four host plant species. Alanine substitution of E109, D173, or E176 reduced the accumulation of virus in agrobacterium-infiltrated tissues, the efficiency of systemic infection, and the efficiency of aphid transmission relative to wild-type virus, but the mutations did not affect virion stability. A structural model of the PLRV capsid predicted that the amino acids critical for virion assembly were located within a depression at the center of a coat protein trimer. The other amino acids that affected plant infection and/or aphid transmission were predicted to be located around the perimeter of the depression. PLRV virions play key roles in phloem-limited virus movement in plant hosts as well as in transport and persistence in the aphid vectors. These results identified amino acid residues in a surface-oriented loop of the coat protein that are critical for virus assembly and stability, systemic infection of plants, and movement of virus through aphid vectors.

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Green peach aphid and potato leafroll virus: transmission and control

сборник статей всероссийской научной конференции с международным участием "Растениеводство и луговодство" ◽

10.26897/978-5-9675-1762-4-2020-178 ◽

2020 ◽

Author(s):

R.A. Bagrov ◽

◽

V.I. Leunov

Keyword(s):

Myzus Persicae ◽

Green Peach Aphid ◽

Virus Transmission ◽

Potato Leafroll Virus ◽

Factors Affecting ◽

Potato Viruses ◽

Tuber Necrosis ◽

Aphid Vectors ◽

Leafroll Virus ◽

And Control

The mechanisms of transmission of potato viruses from plants to aphid vectors and from aphids to uninfected plants are described, including the example of the green peach aphid (Myzus persicae, GPA). Factors affecting the spreading of tuber necrosis and its manifestation on plants infected with potato leafroll virus (PLRV) are discussed. Recommendations for PLRV and GPA control in the field are given.

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