Potato Virus Y (PVY) is a potyvirus that infects potatoes and causes mosaic, necrosis, leaf drop, streaking, and stunting symptoms. It is transmitted by the aphid Aphis gossypii and through grafting or sap inoculation. PVY has a single-stranded RNA genome that encodes a single polyprotein later cleaved into 10 functional proteins. It replicates within the cytoplasm of infected plant cells. Its life cycle involves penetration of the host cell, translation and processing of its polyprotein, replication of its genome, assembly of new viral particles, and cell-to-cell movement through the viral protein P3N-PIPO.

1. Dr. Pawan Kumar Kanaujia
Assistant Professor
Molecular Virology (Theory)
Potato Virus Y

2. Potato Virus Y- Symptoms
Symptoms
Mosaic.
Necrosis.
Leaf drop streaking.
Plant Stunting.
Bunching or twisting of leaves

4. Transmitted by aphid
Transmitted by grafting
Transmission
Aphid (Aphis gossypii), grafting and sap inoculation

5. Potato virus Y
Virus classification
(unranked): Virus
Class: Stelpaviricetes
Order: Patatavirales
Family: Potyviridae
Genus: Potyvirus
Species: Potato virus Y

6. Structure
Non-enveloped, flexuous, filamentous,
of 720-850 nm long and 12-15 nm in diameter.
Symmetry helical.
PVY maybe transmitted to potato plants through grafting,
plant sap inoculation and through aphid transmission.
Presence of characteristic inclusion bodies within infected
plant cells.

7. Monopartite,
linear,
ssRNA(+) genome of 10 kb in size
3' terminus has a poly (A) tract
5' terminus has a genome-linked protein (VPg)
This RNA is enclosed in a protein capsid (CP) composed of
up to 2000 subunits of 30–37 kDa

8. GENE EXPRESSION
The virion RNA is infectious and serves as both the
genome and viral messenger RNA.
The genomic RNA is translated into polyproteins which are
subsequently processed by the action of three viral-encoded
proteinases into functional products.
P3N-PIPO is expressed by polymerase slippage mechanism
from the P3 ORF and probably acts as a movement protein.

9. The viral RNA encodes a single, large polyprotein that is cleaved by
three virus-encoded proteases (P1, helper component proteinase,
and the nuclear inclusion body A proteinase) into ten functional
proteins (P1, HC-Pro, P3, 6 K1, CI, 6 K2, VPg, NIa-Pro, NIb, and CP) and
additional peptide P3N-PIPO (Fig. )
Potato Virus Y Genetic Variability: A Review
Rakesh Kumar Verma , Ritesh Mishra , and Rajarshi Kumar Gaur*Department of
Biosciences, College of Arts, Science and Commerce , Mody University of Science
and Technology , Lakshmangarh , Sikar 332311 , Rajasthan , India e-mail:
rkgaur.fasc@modyuniversity.ac.in

11. REPLICATION
CYTOPLASMIC
Virus penetrates into the host cell.
Uncoating, and release of the viral genomic RNA into the cytoplasm.
The viral RNA is translated to produce a polyprotein which is
processed by viral proteases into the RdRp protein and structural
proteins.
Replication takes place in cytoplasmic viral factories. A dsRNA
genome is synthesized from the genomic ssRNA(+).
The dsRNA genome is transcribed/replicated thereby providing viral
mRNAs/new ssRNA(+) genomes.
Virus assembly in the cytoplasm.
Viral movement protein P3N-PIPO probably mediates virion cell-to-
cell transfer.

12. Potato Virus Y life cycle

13. Potato virus Y: biodiversity, pathogenicity, epidemiology and management pp 1-
19| Cite as General Characteristics of Potato virus Y (PVY) and Its Impact on Potato
Production: An Overview

15. Thank you