# A peptide derived from sorting nexin 1 inhibits HPV16 entry, retrograde trafficking, and L2 membrane spanning

## TL;DR

A peptide from sorting nexin 1 blocks HPV16 infection by inhibiting viral entry and trafficking, offering a potential new treatment for cervical cancer.

## Contribution

The study demonstrates a novel application of SNX1.3 in inhibiting HPV16 infection through retrograde trafficking and L2 membrane spanning.

## Key findings

- SNX1.3 delays HPV16 virion endocytosis and blocks retrograde trafficking and Golgi localization.
- SNX1.3 impairs membrane spanning of the HPV16 minor capsid protein L2.
- The peptide does not affect cell proliferation or post-Golgi trafficking of HPV16.

## Abstract

High risk human papillomavirus (HPV) infection is responsible for 99 % of cervical cancers and 5 % of all human cancers worldwide. HPV infection requires the viral genome (vDNA) to gain access to nuclei of basal keratinocytes of epithelium. After virion endocytosis, the minor capsid protein L2 dictates the subcellular retrograde trafficking and nuclear localization of the vDNA during mitosis. Prior work identified a cell-permeable peptide termed SNX1.3, derived from the BAR domain of sorting nexin 1 (SNX1), that potently blocks the retrograde and nuclear trafficking of EGFR in triple negative breast cancer cells. Given the importance of EGFR and retrograde trafficking pathways in HPV16 infection, we set forth to study the effects of SNX1.3 within this context. SNX1.3 inhibited HPV16 infection by both delaying virion endocytosis, as well as potently blocking virion retrograde trafficking and Golgi localization. SNX1.3 had no effect on cell proliferation, nor did it affect post-Golgi trafficking of HPV16. Looking more directly at L2 function, SNX1.3 was found to impair membrane spanning of the minor capsid protein. Future work will focus on mechanistic studies of SNX1.3 inhibition, and the role of EGFR signaling and SNX1-mediated endosomal tubulation, cargo sorting, and retrograde trafficking in HPV infection.