ChIP-seq: The newborn (P1) lenses of CD-1 mice (Charles River Laboratories) were dissected, tissue was freshly crosslinked and homogenized. Sonicated lysates were clarified and histone-DNA complexes were isolated with antibody. αTN4 cells were freshly crosslinked and homogenized in the culture dish. Sonicated lysates were clarified and histone-DNA complexes were isolated with antibody. Libraries were prepared according to Illumina's instructions.