Arabidopsis INHIBITOR OF GROWTH 2 promotes flowering by regulating NuA4-dependent H4 acetylation levels at FT and SOC1.

Barrero-Gil, JavierMouriz, AlfonsoPiqueras, RaquelTian, YingnanLópez, Juan AVázquez, JesúsCrevillén, PedroJarillo, José APiñeiro, Manuel2025-12-152025-12-152025-10-31Plant Physiol. 2025 Oct 31;199(3):kiaf511.https://hdl.handle.net/20.500.12105/27025INHIBITOR OF GROWTH (ING) proteins are chromatin readers that bind trimethylated histone H3 lysine (K) 4 (H3K4me3) marks and associate with either histone acetyltransferase or deacetylase complexes to activate or repress gene transcription, respectively. In plants, there are two types of ING proteins, namely ING1 and ING2. Here, we report that Arabidopsis thaliana ING2 associates with multiple subunits of the histone H4 acetyltransferase complex NuA4, controls genome-wide levels of histone H4 acetylation (H4ac), and regulates different developmental processes, including the initiation of flowering. Our data indicate that ING2 biological functions are largely independent of ING1 activity. We find that ING2 is recruited to the chromatin of key floral integrators, such as FT and SOC1, and is required for their timely activation by modulating histone H4ac levels at these loci. Our observations reveal a genetic interaction between ING2 and genes encoding relevant proteins for H3K4me3 or H2A.Z deposition, suggesting that ING2 might represent a hub for potential crosstalk between histone H4ac and these histone modifications/variants.This study is supported by competitive grants PID2022-137131NB-I00 to J.A.J. and M.P. and PID2021-122348NB-I00 funded by MCIN/AEI/10.13039/501100011033/FEDER, UE; and by “the Comunidad de Madrid grant S2022/BMD-7333-CM and la Caixa Foundation grant LCF/PR/HR22/52420019 to J.V. A.M. was granted with a FPU fellowship from the Spanish Ministry of Education and Y.T. is recipient of the Chinese Scholarship Council (CSC) predoctoral fellowship 202109210045. The CBGP is a Severo Ochoa Center of Excellence (grant CEX2020-000999-S funded by MICIU/AEI/10.13039/501100011033). The CNIC is supported by the Instituto de Salud Carlos III (ISCIII), the Ministerio de Ciencia, Innovación Y Universidades (MICIU) and the Pro CNIC Foundation), and is a Severo Ochoa Center of Excellence (grant CEX2020-001041-S funded by MICIU/AEI/10.13039/501100011033).engVoRhttp://creativecommons.org/licenses/by/4.0/Arabidopsis INHIBITOR OF GROWTH 2 promotes flowering by regulating NuA4-dependent H4 acetylation levels at FT and SOC1.Attribution 4.0 International41100683PLANT PHYSIOLOGYopen access