Arabidopsis Floral Initiator SKB1 Confers High Salt Tolerance by Regulating Transcription and Pre-mRNA Splicing through Altering Histone H4R3 and Small Nuclear Ribonucleoprotein LSM4 Methylation

• Published in: The Plant cell 2011, Vol.23 (1), p.396-411
• Main Authors: Zhang, Zhaoliang, Zhang, Shupei, Zhang, Ya, Wang, Xin, Li, Dan, Li, Qiuling, Yue, Minghui, Li, Qun, Zhang, Yu-e, Xu, Yunyuan, Xue, Yongbiao, Chong, Kang, Bao, Shilai
• Format: Article
• Language: English
• Subjects: Abscisic Acid - pharmacology; Arabidopsis; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Chromatin; Development; DNA methylation; Flowering; Flowers - growth & development; Gene Expression Profiling; Gene expression regulation; Gene Expression Regulation, Plant; Genes; Growth rate; Histones; Histones - metabolism; Hypersensitivity; Integration; MADS Domain Proteins - metabolism; Methylation; Mutation; Oligonucleotide Array Sequence Analysis; Plant cells; Plants; Ribonucleoproteins (small nuclear); Ribonucleoproteins, Small Nuclear - genetics; Ribonucleoproteins, Small Nuclear - metabolism; RNA Precursors - metabolism; RNA Splicing; RNA, Plant - metabolism; Salt tolerance; Salt-Tolerant Plants - genetics; Salt-Tolerant Plants - growth & development; Salt-Tolerant Plants - metabolism; Salts; Seedlings; Splicing; Stress; Transcription; Transcription, Genetic
• ISSN: 1040-4651; 1532-298X
• DOI: 10.1105/tpc.110.081356

Plants adapt their growth and development in response to perceived salt stress. Although DELLA-dependent growth restraint is thought to be an integration of the plant's response to salt stress, little is known about how histone modification confers salt stress and, in turn, affects development. Here, we report that floral initiator Shk1 kinase binding protein1 (SKB1) and histone4 arginine3 (H4R3) symmetric dimethylation (H4R3sme2) integrate responses to plant developmental progress and salt stress. Mutation of SKB1 results in salt hypersensitivity, late flowering, and growth retardation. SKB1 associates with chromatin and thereby increases the H4R3sme2 level to suppress the transcription of FLOWERING LOCUS C (FLC) and a number of stress-responsive genes. During salt stress, the H4R3sme2 level is reduced, as a consequence of SKB1 disassociating from chromatin to induce the expression of FLC and the stress-responsive genes but increasing the methylation of small nuclear ribonucleoprotein Sm-like4 (LSM4). Splicing defects are observed in the skb1 and lsm4 mutants, which are sensitive to salt. We propose that SKB1 mediates plant development and the salt response by altering the methylation status of H4R3sme2 and LSM4 and linking transcription to pre-mRNA splicing.