Investigation of the Role of Dynein Intermediate Chain (IC) Isoforms in Pseudorabies Virus Post-­Entry Retrograde Transport

Abstract

Alpha herpesviruses are a family of neurotropic DNA viruses that replicate quickly in epithelial cells, and establish a latent phase in sensory ganglia neurons. Herpes simplex virus 1 (HSV‐1) and pseudorabies virus (PRV) are typical members of this family. A trademark of alpha herpesviruses is the bidirectional (anterograde and retrograde) transport capability of virions within and in between neurons. The machinery and mechanisms underlying retrograde transport of viral particles after entry remain nebulous, particularly in neurons. We know that viral nucleocapsids remain attached to the inner tegument proteins such as UL36, and interaction of this protein with motor protein dynein is required for retrograde transport of viral capsids. Moreover, PRV infection induces new protein synthesis in axons, which results in the local translation of several cytoskeletal, trafficking, and signaling proteins including a dynein regulator. Here I aim to examine the role of the dynein intermediate chain (IC) isoforms IC‐1B, neuronal, and IC‐2C, ubiquitous, in retrograde transport of PRV particles and mitochondria. I will demonstrate the functionality of our IC­‐GFP isoforms using a variety of in vitro studies (Chapter 2). Then, I will examine the interaction and co­‐transport of PRV capsids with the IC­‐GFP isoforms using in vitro analysis and live cell imaging in primary neurons and RAT‐2 cells. I will also study the effects of axon damage in PRV co­‐transport with the IC‐ GFP isoforms (Chapter 3). Lastly, I will investigate the role of the IC‐GFP isoforms in co­‐transport of mitochondria in SCG neurons and the effects of axonal damage on mitochondria transport and motility (Chapter 4). Through these experiments, I illustrate the pivotal role of different IC isoforms in retrograde transport of PRV virions and organelles in neurons.