# New tools to target, identify and characterize astrocytes in the adult nervous system

> **NIH NIH R01** · UNIVERSITY OF CALIFORNIA LOS ANGELES · 2020 · $1,090,425

## Abstract

SUMMARY
In order to understand how the CNS encodes, modifies, stores and retrieves information it is necessary to
explore the diverse cell populations that comprise the CNS. There is an emerging consensus that the CNS
cannot be satisfactorily understood solely as a collection of circuits1. One significant missing aspect in our
collective strategy to comprehensively understand the CNS is the largely unmet need to understand additional
cell types such as astrocytes1. Astrocytes represent around 40% of all CNS cells and are found throughout
the brain. Their close proximity to neurons has been known for over a century. It is now well established that
astrocytes serve vital support roles including buffering of K+ around neurons, clearing neurotransmitters from
synapses as well as providing nutrients. Astrocytes may also regulate blood flow to meet demands set by
neuronal activity. In addition to these varied supportive roles, increasing evidence suggests that astrocytes
regulate neuronal function via synapse formation, synapse removal, and regulation of synaptic function
through uptake and release of neuromodulators and neurotransmitters. In addition, astrocytes are proposed
to engage in bidirectional communication with neurons in a Ca2+-dependent manner, which in some
circumstances involves bidirectional ATP signaling. However, despite progress, experimental studies of
astrocytes have lagged behind those of neurons by decades, largely because twentieth century neuroscience
was dominated by the emergent field of electrophysiology that provided a precise and valuable way to study
electrical activity in neurons and its relationship to neural circuit function and behavior. In contrast, astrocytes
do not fire action potentials or display any other type of propagated electrical signals, and thus
electrophysiology was ill suited to study these cells. As a result, our understanding of astrocytes, their identity,
diversity and dynamics is still in its infancy. We seek to capitalize on recent breakthroughs in our laboratories
to advance tools that will allow neuroscientists to study in detail the molecular make-up of astrocytes in
different brain areas at multiple levels from gene expression, to proteins (Aim 1), to physiology within neural
circuit functions in vivo (Aim 2). We will also provide tools to target astrocytes in a selective and non-invasive
manner by gene delivery across the blood-brain-barrier (Aim 3). Our overarching hypothesis is that the
availability and open dissemination of new, selective tools to study astrocytes at molecular, cellular and circuit
levels of investigation may reveal insights about the CNS as striking and as influential as those revealed by
early measurements of electrical signals in neurons. Furthermore, the free dissemination of such tools will
catalyze additional advances in the context of physiology and brain disease.

## Key facts

- **NIH application ID:** 9960483
- **Project number:** 5R01DA047444-03
- **Recipient organization:** UNIVERSITY OF CALIFORNIA LOS ANGELES
- **Principal Investigator:** Viviana Gradinaru
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $1,090,425
- **Award type:** 5
- **Project period:** 2018-09-15 → 2023-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9960483

## Citation

> US National Institutes of Health, RePORTER application 9960483, New tools to target, identify and characterize astrocytes in the adult nervous system (5R01DA047444-03). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/9960483. Licensed CC0.

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