# Mechanisms of autophagic dysfunction in progranulin-related neurodegeneration

> **NIH NIH F30** · NORTHWESTERN UNIVERSITY · 2021 · $51,036

## Abstract

PROJECT SUMMARY
As cells age, protein quality control becomes increasingly important. Accumulated stressors such as starvation,
oxidative damage, and infections lead to organelle dysfunction and protein misfolding. Stem cells, such as those
present in the skin, gut, and blood, can dilute these insults through cell division. Neurons and other post-mitotic
cells, however, must confront them directly. Autophagy, or lysosome-mediated degradation, is the primary
mechanism for clearing large dysfunctional entities within the cell. Neuronal autophagy must be especially robust
for two main reasons: 1) the high rates of protein synthesis and ATP generation in neurons entail a higher
incidence of misfolded proteins and reactive oxygen species, both of which damage the cell, and 2) high spatial
separation of multiple specialized regions (e.g. axons, dendrites, synapses) demands local clearance of damage
in those areas to prevent key functional loss. Predictably, errors in autophagy often affect the aging nervous
system. Frontotemporal dementia (FTD), a progressive neurocognitive disease, is associated with several
single-gene mutations involved in autophagy and broader protein quality control. Many of these genes overlap
with those implicated in amyotrophic lateral sclerosis (ALS), a common neuromuscular disease. Progranulin
(PGRN), a monogenic cause of FTD and risk modifier for ALS, is a lysosomal glycoprotein that causes defects
in autophagy through an unknown mechanism. Recent work by our lab has demonstrated that another ALS-
associated protein, annexin A11 (ANXA11), shows decreased recruitment to the lysosome in PGRN deficient
neurons. ER exit site (ERES) proteins, which regulate protein export from the endoplasmic reticulum, also show
decreased lysosomal recruitment in PGRN deficiency. ANXA11 is known to bind members of ERESs, as well as
to associate physically with the lysosome. Furthermore, ERESs may be involved in more than just protein export.
Our collaborators recently discovered a phenomenon where lysosomes directly engulf and degrade ERESs
bearing misfolded proteins—a clear example of autophagic involvement. I propose to test the hypothesis that
PGRN regulates ERES autophagy through ANXA11 action by addressing the following specific aims: 1)
determine how PGRN regulates ANXA11 interaction with lysosome-organelle contact sites in iPSC-derived
neurons, and 2) determine how PGRN and ANXA11 jointly regulate autophagic activity. I will use a combination
of sophisticated microscopy techniques, biochemical protein identification, and targeted genetic manipulation to
complete these aims. Uncovering the mechanism of PGRN-related neurodegeneration could lead to a better
understanding of the shared pathophysiology of FTD and ALS, providing new drug targets for these incurable
and universally devastating diseases of aging.

## Key facts

- **NIH application ID:** 10084792
- **Project number:** 5F30AG060722-03
- **Recipient organization:** NORTHWESTERN UNIVERSITY
- **Principal Investigator:** Michael Fernandopulle
- **Activity code:** F30 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $51,036
- **Award type:** 5
- **Project period:** 2018-12-01 → 2022-11-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10084792

## Citation

> US National Institutes of Health, RePORTER application 10084792, Mechanisms of autophagic dysfunction in progranulin-related neurodegeneration (5F30AG060722-03). Retrieved via AI Analytics 2026-05-21 from https://api.ai-analytics.org/grant/nih/10084792. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*