Potato virus X coat protein (PVX CP)

Potato virus X coat protein (PVX CP) is a 25 kDa structural subunit that self-assembles into the filamentous, flexible capsid of the Potato virus X (PVX), a member of the Alphaflexiviridae family. Approximately 1,300 CP subunits wrap around the viral RNA genome to form a rod-shaped virion, which is essential for protecting the genetic material and facilitating systemic movement within host plants such as potato and tobacco. In plant pathology, the CP serves as a specific elicitor for the Rx1 resistance gene, triggering a hypersensitive response that limits viral spread. In the field of nanomedicine, PVX CP has gained significant attention as a versatile platform for the development of viral nanoparticles (VNPs) and vaccine delivery systems. The protein's structure allows for the genetic fusion of epitopes or the chemical conjugation of imaging agents and drugs like doxorubicin, which can intercalate between CP subunits for targeted transport. These engineered particles are utilized to improve drug solubility, enhance tumor-homing through the enhanced permeability and retention effect, and can act as potent adjuvants by triggering Toll-like receptors. Despite its potential in biomedical applications, its use is accompanied by challenges such as potential immunogenicity and the need for rigorous safety assessments regarding the use of plant-derived proteins in human patients.

Other names

Capsid proteinCoat proteinCPPVX-CP

Functions as a structural scaffold for the assembly of viral nanoparticles that can carry therapeutic payloads through subunit intercalation or surface chemical conjugation, while also acting as an elicitor that triggers the Rx1-mediated immune response in host plants.