HAC1 and HAF1 Histone Acetyltransferases Have Different Roles in UV-B Responses in Arabidopsis

FINA, JULIETA;; FIORELLA MASOTTI; SEBASTIÁN P. RIUS; FRANCO CREVACUORE; PAULA CASATI

Frontiers in Plant Science

Nature

Año: 2017

Arabidopsis has 12 histone acetyltransferases grouped in four families: the GNAT/HAG,the MYST/HAM, the p300/CBP/HAC and the TAFII250/HAF families. We previouslyshowed that ham1 and ham2 mutants accumulated higher damaged DNA after UV-Bexposure than WT plants. In contrast, hag3 RNA interference transgenic plants showedless DNA damage and lower inhibition of plant growth by UV-B, and increased levelsof UV-B-absorbing compounds. These results demonstrated that HAM1, HAM2, andHAG3 participate in UV-B-induced DNA damage repair and signaling. In this work, tofurther explore the role of histone acetylation in UV-B responses, a putative function ofother acetyltransferases of the HAC and the HAF families was analyzed. Neither HACnor HAF acetyltrasferases participate in DNA damage and repair after UV-B radiationin Arabidopsis. Despite this, haf1 mutants presented lower inhibition of leaf and rootgrowth by UV-B, with altered expression of E2F transcription factors. On the other hand,hac1 plants showed a delay in flowering time after UV-B exposure and changes in FLCand SOC1 expression patterns. Our data indicate that HAC1 and HAF1 have crucialroles for in UV-B signaling, confirming that, directly or indirectly, both enzymes also havea role in UV-B responses.