To determine spatial and temporal patterns of Mll1 expression in the mouse retina, we analyzed Mll1 transcript levels and distribution during development. Quantitative real-time PCR (qRT-PCR) assays with Mll1-specific “Primer Set 1” (Fig. 1A, Supplementary Table S1) showed that Mll1 expression was constant from Postnatal day 0 (P0) to P5, but significantly increased in the second postnatal week (Fig. 1B), the crucial period for terminal differentiation of retinal neurons.
