Coordination of germline chromatin organization mechanisms to initiate embryogenesis
openNIGMS - National Institute of General Medical Sciences
SUMMARY
The extensive epigenetic information associated with genomic DNA establishes a defined chromatin organization
that instructs tissue-specific gene expression programs. Many devastating disorders, diseases, and cancers are
attributed to disruption of chromatin-based regulation, yet the mechanistic underpinnings remain poorly
understood, especially in vivo. Our research program leverages powerful genetic, molecular and genomic tools
to investigate the causal regulatory mechanisms that govern chromatin organization and gene expression in the
C. elegans germ line, an ideal system in which to address these questions. By combining technical and
conceptual innovation, we have discovered many epigenetic mechanisms by which germ cells establish and
balance robust activation and precise repression, at the level of individual genes and across large chromosomal
domains, to ensure successful gametogenesis, fertilization, and embryogenesis. In our recent work, we used
our ability to isolate germ nuclei for genomic analysis to define novel chromatin states in germ cells, identify a
novel protein that links histone modifications to co-transcriptional splicing, discover a unique chromatin state that
promotes the biogenesis of small noncoding piRNAs, and investigate how nucleosome remodeling in the
germline promotes embryogenesis. Our current and future research is organized around investigating how
germline epigenetic mechanisms anticipate and direct embryonic differentiation and development. Specifically,
we will use cutting-edge, highly specific, genomic and perturbation approaches to determine how remodeling of
nucleosome positioning and histone modification patterns shape the dynamic expression of germline-expressed
genes, thereby coordinating maternally-provided factors to carry out successful fertilization, eggshell formation,
asymmetric cell division, early blastomere identity, and onset of zygotic transcription in the embryo. Our
innovative and comprehensive approaches position us to investigate these mechanisms in vivo at a scale and
level of resolution not previously possible. These research directions will therefore uncover novel, fundamental
mechanisms of genetic regulation and reveal causal relationships between chromatin state, gene expression
and cellular function. The specific factors we focus on are highly conserved core regulators of chromatin state
and gene regulation and therefore have substantial influence on gene expression in humans as well, ensuring
broad applicability of our discoveries to understanding development and combating disease.
Up to $538K
health research