Analysis of histone gene H3.3 dynamics during embryonic development.
Ng, Yan Jun.
Date of Issue2011
School of Biological Sciences
A*STAR Institute of Medical Biology
During embryonic development, the spatial and temporal expression of developmental genes is a highly regulated process mediated by epigenetic mechanisms, which includes site-specific incorporation of histone variant H3.3. H3.3 has been implicated in the proper development of mouse pre-implantation embryos but its involvement in later stages of development remains unknown. To understand the role H3.3 may play in regulating cellular differentiation and lineage specification during post-implantation embryonic development, I mapped the gene expression patterns of H3.3 and associated chromatin factors in 6.5 – 10.5 dpc mouse embryos. Whole embryo in situ hybridization analyses revealed expression of H3.3 in all embryonic tissues in 6.5 – 8 dpc embryos. H3.3 becomes restricted to the limb and tail buds in 9.5 – 10.5 dpc embryos suggesting that H3.3 potentially mediates mesodermal lineage differentiation at these stages. Associated chromatin factors Dek and Smarca4 were found to display similar expression patterns, suggesting possible interactions in assisting H3.3-mediated mesoderm regulation. To facilitate additional studies of H3.3 regulation during cellular differentiation, I have also established mouse embryonic stem cell (mESC) lines stably expressing tetracycline repressor (TetR). These cell lines will be useful for analyzing the effects of Dek and Smarca4 knockdown on mesodermal lineage differentiation through a Tet-inducible knockdown system.
Final Year Project (FYP)
Nanyang Technological University