Project Overview

Endogenous retrovirus-K (ERVK) is a genomic viral symbiont that contributes towards ALS neuropathology. Our collaboration proposes to examine how ERVK integrase (IN) enzyme activity drives DNA damage, TDP-43 deregulation and neuronal loss, leading to motor disturbances using a novel ERVK IN transgenic mouse model system. The intent of this proposal is to develop and characterize a pre-clinical mammalian model of ERVK-driven neurodegeneration. This system may be used in the future to evaluate candidate antiviral drugs for ALS clinical trials.

Aim #1: Generation and validation of a conditional Cre/loxP ERVK IN transgenic mouse line.
Aim #2: Assessing motor function in tissue-specific ERVK IN transgenic murine models.
Aim #3: Assessing neuropathology in tissue-specific ERVK IN transgenic murine models.

We propose to develop a Rosa26 locus (R26) based conditional ERVK IN transgenic mouse line, through the extensive expertise of the Haigh lab at the University of Manitoba. Using a Cre/loxP strategy, F1 offspring will co-express both ERVK IN and IRES-driven EGFP from the R26 locus in a cell/tissue specific manner when loxP-stop-loxP-ERVK IN transgenic mice are crossed with an appropriate Cre driver line (pan-neuronal, motor neuron or astrocyte specific drivers). The ERVK IN transgenic mice and littermate controls will be evaluated for motor function over time using standard open field tests, rotor-rod and non-invasive 24-hour cage monitoring. At humane endpoint or completion of 9-month study period, paired transgenic-littermate control brain specimens will be examined for neuropathological markers associated with DNA damage, neuronal loss, TDP-43 deregulation and neuroinflammation using both confocal microscopy and Western blot analyses. Statistical analysis will consider group-specific, sex-specific and endpoint timing comparisons, with Kaplan-Meier survival analysis, group analysis of individual readouts and correlation of motor function with neuropathological markers. Establishing this transgenic model will also allow for future drug screening of integrase inhibitors and identification of top candidate drugs to target ERVK IN activity.

Principal Investigator

Renée Douville , University of Manitoba

Partners and Donors

ALS Canada