Understanding the roles of cellular RNA-binding proteins in HIV-1 infection

Thesis

The Human Immunodeficiency virus type 1 (HIV-1) is the causative agent of Acquired Immune Deficiency Syndrome (AIDS) which is currently estimated to affect 37.9 million people globally, representing a serious threat to global health. Developing a fundamental understanding of the HIV-1 life cycle is paramount in the search for a cure. RNA is a central molecule in HIV-1 biology due to its dual function as messenger and genome. However, the small number of proteins encoded by HIV-1 is insufficient to enable virus infection. Hence, HIV-1 hijacks cellular RNA-binding proteins (RBPs) to fulfil its life cycle. Using in virion RNA-interactome capture we identified 104 cellular RBPs interacting with HIV-1 RNA within the viral capsid. My DPhil aimed to identify which of these RBPs regulate HIV-1 infection. By screening RBP-knockout cell lines I uncovered the effects of MKRN1, FAM120A, LSM14A, MSN, LCK, CIRBP and YBX3 on HIV-1 infection. Further analysis into the role of MKRN1 revealed a novel function for MKRN1 in the positive regulation of HIV-1 viral particle release from the plasma membrane. Additionally, I have developed a tool, HIV-1INscarlet, to enable the visualisation of the early stages of HIV-1 infection from viral particle entry to integration using super-resolution microscopy. This tool will allow for future experiments into the role of MKRN1 inside the HIV-1 capsid during the early stages of infection. Together, this work highlights novel cellular regulators of HIV-1 infection and further validates the crucial role conducted by cellular RBPs in HIV-1 infection.

Authors: Dicker, K

• DOI: 10.5287/ora-mj1gvrrdo
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: University of Oxford
• Language: English
• Keywords: host-pathogen interaction; RNA-binding protein; virus; HIV-1; MKRN1
• Subjects: HIV (Viruses); RNA-protein interactions