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The MADS-box genes are an important class of transcription factors and play critical roles in flower development. However, the functions of these genes in the economically important drinking plant, Camellia sinensis, are still not reported. Here, an evolutionary analysis of tea MADS-box genes was performed at whole genome level. A total of 83 MADS-box genes were identified in tea, and their gene structures and expression patterns were further analyzed. The tea MADS-box genes were classified into Mα (26), Mβ (12), Mγ (9), MIKC* (7), and MIKCC (29) clade according to their phylogenetic relationship with Arabidopsis thaliana. Several cis-elements were identified in the promoter regions of the CsMADS genes that are important in regulating growth, development, light responses, and the response to several stresses. Most CsMADS genes display clear different expression patterns in different organs and different species of tea plant. The expression of CsMADS genes can be regulated by abiotic stresses and phytohormone treatment. Our results lay the foundation for future research on the function of CsMADS genes and beneficial for improving tea agricultural traits in the future. [ABSTRACT FROM AUTHOR]

Histone acetylation and deacetylation at the N-terminus of histone tails play crucial roles in the regulation of eukaryotic gene activity. Histone acetylation and deacetylation are catalyzed by histone acetyltransferases and histone deacetylases (HDACs), respectively. A growing number of studies have demonstrated the importance of histone deacetylation/acetylation on genome stability, transcriptional regulation, development and response to stress in Arabidopsis. However, the biological functions of HDACs in tomato have not been investigated previously. Fifteen HDACs identified from tomato (Solanum Lycopersicum) can be grouped into RPD3/HDA1, SIR2 and HD2 families based on phylogenetic analysis. Meanwhile, ten members of the RPD3/HDA1 family can be further subdivided into four groups, namely Class I, Class II, Class III and Class IV. High similarities of protein sequences and conserved domains were identified among SlHDACs and their homologs in Arabidopsis. Most SlHDACs were expressed in all tissues examined with different transcript abundance. Transient expression in Arabidopsis protoplasts showed that SlHDA8, SlHDA1, SlHDA5, SlSRT1 and members of the HD2 family were localized to the nucleus, whereas SlHDA3 and SlHDA4 were localized in both the cytoplasm and nucleus. The difference in the expression patterns and subcellular localization of SlHDACs suggest that they may play distinct functions in tomato. Furthermore, we found that three members of the RPD3/HDA1 family, SlHDA1, SIHDA3 and SlHDA4, interacted with TAG1 (TOMATO AGAMOUS1) and TM29 (TOMATO MADS BOX29), two MADS-box proteins associated with tomato reproductive development，indicating that these HDACs may be involved in gene regulation in reproductive development.

Histone acetylation and deacetylation at the N-terminus of histone tails play crucial roles in the regulation of eukaryotic gene activity. Histone acetylation and deacetylation are catalyzed by histone acetyltransferases and histone deacetylases (HDACs), respectively. A growing number of studies have demonstrated the importance of histone deacetylation/acetylation on genome stability, transcriptional regulation, development and response to stress in Arabidopsis. However, the biological functions of HDACs in tomato have not been investigated previously. Fifteen HDACs identified from tomato (Solanum lycopersicum) can be grouped into RPD3/HDA1, SIR2 and HD2 families based on phylogenetic analysis. Meanwhile, 10 members of the RPD3/HDA1 family can be further subdivided into four groups, namely Class I, Class II, Class III, and Class IV. High similarities of protein sequences and conserved domains were identified among SlHDACs and their homologs in Arabidopsis. Most SlHDACs were expressed in all tissues examined with different transcript abundance. Transient expression in Arabidopsis protoplasts showed that SlHDA8, SlHDA1, SlHDA5, SlSRT1 and members of the HD2 family were localized to the nucleus, whereas SlHDA3 and SlHDA4 were localized in both the cytoplasm and nucleus. The difference in the expression patterns and subcellular localization of SlHDACs suggest that they may play distinct functions in tomato. Furthermore, we found that three members of the RPD3/HDA1 family, SlHDA1, SIHDA3 and SlHDA4, interacted with TAG1 (TOMATO AGAMOUS1) and TM29 (TOMATO MADS BOX29), two MADS-box proteins associated with tomato reproductive development, indicating that these HDACs may be involved in gene regulation in reproductive development. [ABSTRACT FROM AUTHOR]

• Ca2+-modulated dehydration responses in rice is influenced by altered physicochemical properties and proteome dynamics. • Proteomic analysis revealed 56 proteins presumably associated with Ca2+-signalling and adaptive responses to dehydration. • Dehydration-induced altered expression of MADS-box protein, OsMADS23, indicated its role in calcium-dependent cell defense. The cytosolic Ca2+ ([Ca2+]cyt), in plants serves as secondary messenger during development and stress adaptive responses. While several of the components of Ca2+-signalling, especially involved in water-deficit stress or dehydration are known, the underlying mechanism of such regulations remain poorly understood. In this study, we investigated the Ca2+-mediated alleviation of dehydration stress in rice. The physicochemical indices of the rice seedlings pretreated with CaCl 2 , followed by dehydration treatment displayed better maintenance of relative water content (RWC) and cell membrane integrity, besides peroxide levels. CaCl 2 -pretreated seedling showed stimulation of antioxidants contributing to long-term survival under dehydration stress. Contrastingly, blocking of Ca2+-channels aggravated the dehydration-induced damage, suggesting a crucial role of Ca2+-signalling in stress adaptation. The cytosolic proteome profiling of CaCl 2 -pretreated seedlings revealed 100 distinct proteins that include 56 dehydration-responsive proteins (DRPs), presumably involved in adaptive responses. A critical screening of the proteome led to the identification of a MADS-box transcription factor family protein, designated OsMADS23. The predicted structure and nuclear localization indicated that OsMADS23 might bind to nucleic acids, suggesting its possible role in transcriptional regulation. The stimulation of stress-responsive expression of OsMADS23 by Ca2+ demonstrated its participation in Ca2+-dependent signalling. Altogether, these results indicate the Ca2+-dependent dehydration response in plants and substantiate the function of a MADS-box protein in the cross-talk of developmental and stress-responsive pathways. [ABSTRACT FROM AUTHOR]

Histone acetylation and deacetylation at the N-terminus of histone tails play crucial roles in the regulation of eukaryotic gene activity. Histone acetylation and deacetylation are catalyzed by histone acetyltransferases and histone deacetylases (HDACs), respectively. A growing number of studies have demonstrated the importance of histone deacetylation/acetylation on genome stability, transcriptional regulation, development and response to stress in Arabidopsis. However, the biological functions of HDACs in tomato have not been investigated previously. Fifteen HDACs identified from tomato (Solanum lycopersicum) can be grouped into RPD3/HDA1, SIR2 and HD2 families based on phylogenetic analysis. Meanwhile, 10 members of the RPD3/HDA1 family can be further subdivided into four groups, namely Class I, Class II, Class III, and Class IV. High similarities of protein sequences and conserved domains were identified among SlHDACs and their homologs in Arabidopsis. Most SlHDACs were expressed in all tissues examined with different transcript abundance. Transient expression in Arabidopsis protoplasts showed that SlHDA8, SlHDA1, SlHDA5, SlSRT1 and members of the HD2 family were localized to the nucleus, whereas SlHDA3 and SlHDA4 were localized in both the cytoplasm and nucleus. The difference in the expression patterns and subcellular localization of SlHDACs suggest that they may play distinct functions in tomato. Furthermore, we found that three members of the RPD3/HDA1 family, SlHDA1, SIHDA3 and SlHDA4, interacted with TAG1 (TOMATO AGAMOUS1) and TM29 (TOMATO MADS BOX29), two MADS-box proteins associated with tomato reproductive development, indicating that these HDACs may be involved in gene regulation in reproductive development.