Project Summary
Myelin is critical for proper brain function and its dysfunction, damage or inappropriate formation has been
reported in a wide range of neurological and psychiatric disorders, thereby urging the discovery of new potential
treatments. This fellowship addresses the role of metabolism, and more specifically of glucose-derived acetyl-
CoA (AcCoA), in regulating developmental myelination. The experimental aims rest on the solid premise that
AcCoA is an unstable compound which cannot freely diffuse from one compartment to the next. The overarching
hypothesis is that AcCoA function is dependent on the subcellular localization of its synthetic enzyme ATP citrate
lyase (ACLY) and on the levels of the specific AcCoA transporter to the endoplasmic reticulum, SLC33A1. Aim
1 uses loss- and gain-of-function approaches to test the hypothesis that high glucose levels during the first
postnatal week favor nuclear localization of ACLY and in turn promote synthesis of AcCoA and its incorporation
into histones, thereby resulting in the expression of genes that favor proliferation and the maintenance of the
progenitor state. It also posits that the transient decline of glucose during the second postnatal week is
responsible for decreased nuclear ACLY, decreased nuclear AcCoA thereby favoring histone deacetylation and
the transition of OPC from proliferating to differentiating cells. The hypothesis will be tested using Acly loss- and
gain-of-function approaches in vitro in cultured OPC as well as lineage specific ablation in mice. The genome
wide distribution of select histone acetylation marks will be tested using chromatin immunoprecipitation. Aim 2
uses loss- and gain-of-function approaches to test the hypothesis that increased cytosolic AcCoA synthesis in
differentiating OL, followed by its transport to the endoplasmic reticulum (via SLC33A1) is crucial for the synthesis
of cholesterol and myelin lipids. This hypothesis is supported by the detection of increased myelin in mice with
systemic overexpression of the Slc33a1 transgene. The subaims will address OL differentiation and myelin
development by matrix assisted laser desorption/ionization (MALDI) imaging, and electron microscopy. The
training plan incorporates learning of new skills, such as advanced methodology in epigenetics, bioinformatics,
lentiviral transduction, optogenetics and the latest in mass spectrometry imaging technologies. In addition,
several opportunities will be offered to encourage training in experimental design, data analysis, as well as
improvements in written and oral scientific communication and opportunities to mentor undergraduate students.
Professional development opportunities will be available and participation in local, national, and international
conferences will allow networking. As tangible milestones, the work is expected to result in two high quality, first
author manuscripts as a doctoral trainee, and grant the opportunity to obtain a competitive post-doctoral
appointment, leading to a career in academic science. This fellowship aligns the applicant’s long-term goal of
studying metabolic regulation of brain cells, with the public health mission of NIH and NINDS to foster academic
scientists and steward advances in our understanding of brain development and disease.