Although two Enhancer of Polycomb-like proteins,EPL1 A and EPL1 B(EPL1 A/B),are known to be conserved and characteristic subunits of the Nu A4-type histone acetyltransferase complex in Arabidopsis thaliana,the biologi...Although two Enhancer of Polycomb-like proteins,EPL1 A and EPL1 B(EPL1 A/B),are known to be conserved and characteristic subunits of the Nu A4-type histone acetyltransferase complex in Arabidopsis thaliana,the biological function of EPL1 A/B and the mechanism by which EPL1 A/B function in the complex remain unknown.Here,we report that EPL1 A/B are required for the histone acetyltransferase activity of the Nu A4 complex on the nucleosomal histone H4 in vitro and for the enrichment of histone H4 K5 acetylation at thousands of protein-coding genes in vivo.Our results suggest that EPL1 A/B are required for linking the Nu A4 catalytic subunits HISTONE ACETYLTRANSFERASE OF THE MYST FAMILY 1(HAM1)and HAM2 with accessory subunits in the Nu A4 complex.EPL1 A/B function redundantly in regulating plant development especially in chlorophyll biosynthesis and de-etiolation.The EPL1 A/B-dependent transcription and H4 K5 Ac are enriched at genes involved in chlorophyll biosynthesis and photosynthesis.We also find that EAF6,another characteristic subunit of the Nu A4 complex,contributes to de-etiolation.These results suggest that the Arabidopsis Nu A4 complex components function as a whole to mediate histone acetylation and transcriptional activation specifically at light-responsive genes and are critical for photomorphogenesis.展开更多
基金supported by the National Natural Science Foundation of China(32025003)the National Key Research and Development Program of China(2016YFA0500801)from the Chinese Ministry of Science and Technology。
文摘Although two Enhancer of Polycomb-like proteins,EPL1 A and EPL1 B(EPL1 A/B),are known to be conserved and characteristic subunits of the Nu A4-type histone acetyltransferase complex in Arabidopsis thaliana,the biological function of EPL1 A/B and the mechanism by which EPL1 A/B function in the complex remain unknown.Here,we report that EPL1 A/B are required for the histone acetyltransferase activity of the Nu A4 complex on the nucleosomal histone H4 in vitro and for the enrichment of histone H4 K5 acetylation at thousands of protein-coding genes in vivo.Our results suggest that EPL1 A/B are required for linking the Nu A4 catalytic subunits HISTONE ACETYLTRANSFERASE OF THE MYST FAMILY 1(HAM1)and HAM2 with accessory subunits in the Nu A4 complex.EPL1 A/B function redundantly in regulating plant development especially in chlorophyll biosynthesis and de-etiolation.The EPL1 A/B-dependent transcription and H4 K5 Ac are enriched at genes involved in chlorophyll biosynthesis and photosynthesis.We also find that EAF6,another characteristic subunit of the Nu A4 complex,contributes to de-etiolation.These results suggest that the Arabidopsis Nu A4 complex components function as a whole to mediate histone acetylation and transcriptional activation specifically at light-responsive genes and are critical for photomorphogenesis.