Functional and biochemical characterization of the CHD3 remodeler PICKLE in Arabidopsis

The developmental program of seeds is promoted by master regulators that are expressed in a seed-specific manner. Ectopic expression studies reveal that expression of these master regulators and other transcriptional regulators is sufficient to promote a range of seed-associated traits, including generation of somatic embryos. Recent work highlights the importance of chromatin-associated factors in restricting expression of seed-specific genes, in particular PcG proteins and ATP-dependent chromatin remodelers. Here I summarize my analyses of factors that promote zygotic and/or somatic embryogenesis and the chromatin machinery that represses their expression. My studies concerning the CHD3 chromatin remodeler PICKLE (PKL) indicate it is a major factor involved in repressing seed-specific genes during germination. Furthermore, my studies reveal that PKL and PcG-based chromatin machinery work together to repress expression of seed-specific genes in plants. Biochemical characterization of PKL and its role in the regulation of seed-specific genes reveals that plant chromatin-based repression systems exhibit broad conservation with and surprising differences from animal repression systems.