Figure 4.

A histone H3 K14Q mutation reduces the light response. (A) Phenotypes of Neurospora strains with wild-type histone H3 (WT; N644) and a dominant histone H3 K14Q substitution (hH3^K14Q; N3095). The hH3^K14Q mutant phenocopied wc-1 (FGSC3081) and ngf-1^RIP1 (N2842). Strains were grown on minimal medium for 1 wk in the dark, induced under saturating light, and the production of carotenoids was observed after 6 h at 4°C. (B) Northern analysis of al-3, vvd, and actin (control) revealed light-induced expression in WT. This regulation was abolished in wc-1 and reduced in hH3^K14Q mutants. Densitometric analysis for al-3 (left) and vvd (right) revealed a five- or sevenfold reduction, respectively, in the hH3^K14Q strain compared with wild type (below).