Biological roles and mechanisms of cell surface rnas in human papillomavirus endocytic trafficking

The National Institute of General Medical Sciences awarded the Board of Regents of the University of Nebraska, through its University of Nebraska Medical Center division, $417,845 on April 5, 2026, under the Biomedical Research and Research Training program (CFDA 93.859) to investigate the biological roles and mechanisms of cell surface RNAs in human papillomavirus endocytic trafficking.

The research combines advanced imaging strategies, biochemical techniques, and genetic analysis to decipher the functional roles of cell surface RNA in HPV endocytic trafficking and to identify the specific step in HPV cell entry regulated by cell surface RNAs. The work explores the cell surface RNA binding protein DDX3X, recognition sites for cell surface RNA-DDX3X clustering on HPV cell-penetrating peptides, and glycorna transcripts identified through RNA sequencing. The project also investigates the trafficking modes utilized by cell surface RNAs that are critical for their cell surface presentation and function.

Work is performed in Omaha, Nebraska, with a period of performance from April 5, 2026, through February 28, 2031. The award is classified as a Project Grant.

Abstract

The subcellular localization of a biomolecule often reveals its functional significance. RNA has typically been confined to the cytoplasm and nucleus, where IT is critically involved in numerous biochemical processes. Recently, glycosylated rnas (glycornas) have been discovered on the cell surface of various cell types, raising important questions about their functional relevance, mechanisms of action, and the trafficking pathways that maintain their dynamic equilibrium on the cell surface. The long-term goal of this proposal is to discover and define the functional mechanisms of cell surface rnas in endocytosis and pathogen endocytic trafficking. Preliminary evidence suggests that cell surface rnas are critically required in human papillomavirus (HPV) infection. This mira proposal is firstly focused on deciphering the functional roles of cell surface RNA in HPV endocytic trafficking. Here a combination of advanced imaging strategies, biochemical techniques, and genetic analysis will be used to dissect and determine the specific step in HPV cell entry that is regulated by cell surface rnas. We are also exploring the mechanisms underlying this process by leveraging recent discoveries from my lab, including the identification of the cell surface RNA binding protein (RBP) DDX3X, a potential recognition site for cell surface RNA-DDX3X clustering on the HPV cell-penetrating peptide (CPP), and glycorna transcripts identified through RNA sequencing. Lastly, we are investigating the trafficking modes utilized by cell surface rnas, which are critical for their cell surface presentation and functions. Collectively, this research addresses fundamental questions in cell membrane trafficking and provides valuable insights into the recently discovered cell surface rnas. IT may also introduce a new concept in which cell surface rnas and rbps cluster to form an endocytic receptor complex involved in pathogen cell entry. While many exciting questions LIE beyond the scope of this mira proposal, the findings could stimulate broad interest, offer proof-of-concept frameworks, and develop techniques that enhance our understanding of the role of cell surface rnas in endocytosis and pathogen entry mechanisms.