PROJECT SUMMARY
The purpose of this F31 proposal is to provide support for Cali McEntee, a doctoral student at Colorado State
University (CSU), while she trains to become an independent scientist conducting research on age-related
neurodegeneration. With support from this award, Ms. McEntee will determine if reductions in adenosine
deaminase acting on RNA 1 (ADAR1) lead to the accumulation of double-stranded RNA (dsRNA), a
pathogen-associated molecular pattern that causes innate immune/inflammatory signaling, in the context of
brain aging and Alzheimer’s disease (AD). Numerous reports show that ADAR1 suppresses dsRNA-related
inflammation and may modulate lifespan, and that innate immune activation/neuroinflammation driven by glial
cells, like astrocytes, is a central mechanism of brain aging/AD. The applicant’s preliminary data show that
brain aging/AD are associated with reductions in ADAR1 levels, and that reducing ADAR1 expression in
astrocytes leads to an increase in transcripts from genomic repetitive elements (RE), which are increasingly
implicated in aging and neurodegeneration and predisposed to form dsRNA. As such, ADAR1 may be an
important regulator of neuroinflammation with brain aging and/or AD, perhaps by reducing RE-associated
dsRNA accumulation. However, this idea has not been investigated. In this project, Ms. McEntee proposes to
gain valuable translational research training by using multiple models to test the hypothesis that ADAR1
reduces the deleterious effects of RE-derived dsRNA and thereby protects against age/AD-related
neuroinflammation by: Aim 1) using directly reprogramed human astrocytes from healthy young/older adults
and AD patients to determine if ADAR1 and dsRNA levels are related to neuroinflammation, performing total
RNA-seq and RNA immunoprecipitation sequencing (RIP-seq) to identify RE-derived dsRNAs involved in
neuroinflammation, and intersecting her findings with existing clinical datasets; and Aim 2) increasing
expression of ADAR1 in reprogrammed human astrocytes and a pre-clinical mouse model of aging to
determine if ADAR1 protects against age/AD-related neuroinflammation and cognitive dysfunction. Ms.
McEntee’s immediate goal is to gain the fundamental experience and professional skills necessary to perform
independent research in the field of age-related neurodegenerative diseases. Her long-term goal is to become
an academic, translational researcher investigating mechanisms of aging that contribute to neurodegenerative
disease. Ms. McEntee will train in a state-of-the-art environment with an exceptional mentoring team at CSU.
The sponsor, Dr. LaRocca, has an extensive background studying aging and neurodegenerative diseases and
directs the NIH-funded Healthspan Biology Laboratory at CSU. Under the guidance of Dr. LaRocca and
consulting mentors Drs. Chris Link, Ron Tjalkens, Julie Moreno, and Dan Lark, Ms. McEntee will be able to
successfully complete the training plan, supporting her development into an independent scientist.