Developmental Dynamics of 5-Hydroxymethylcytosine and its Role in the Terminal Differentiation of Neurons

<p>While epigenetic dynamics in mitotic differentiating cells have been characterized in depth, little is known about how postmitotic neurons regulate their chromatin state. Modulation of transcription through the regulation of accessibility of transcription factor binding sites is essential for the regulation of migration, synapse formation and terminal differentiation. Although 5-hydroxymethylcytosine (5hmC), the oxidized form of 5-methylcytosine, accumulates to high levels in neuronal lineages and refines the genomic binding of MeCP2, the functional consequences of 5hmC deposition in differentiating neurons have not been determined. We report high resolution characterization of the genomic landscape of developing postmitotic Purkinje neurons, confirm the relationship between 5hmC and gene expression and identify a novel class of genes that are demethylated in the absence of cell division. Deletion of the 5hmC writers Tet1, Tet2, and Tet3 from postmitotic Purkinje cells alters cytosine modification in regulatory domains, impairs gene expression, hinders developmental transitions, and causes hyper-excitability and increased susceptibility to excitotoxic drugs. These data demonstrate that 5hmC and the Tet proteins are required for terminal differentiation of Purkinje cells through demethylation of important regulatory regions. Our data, along with recent reports of the role of Tet proteins in neurodegeneration suggest an essential role in development and function of all neurons.</p>

Name thesis:degree_name

Doctor of Philosophy (PhD)

Level thesis:degree_level

Thesis

Year

2021

Author dc:creator

• Stoyanova, Elitsa

Contributors dc:contributor

• Nathaniel Heintz

• epigenetic dynamics
• postmitotic neurons
• 5-hydroxymethylcytosine
• Tet proteins
• Purkinje cells
• terminal differentiation
• Life Sciences

Repository record dc:identifier

https://digitalcommons.rockefeller.edu/student_theses_and_dissertations/646

OAI identifier oai:identifier

oai:digitalcommons.rockefeller.edu:student_theses_and_dissertations-1645