The Spt-Ada-Gcn5-acetyltransferase (SAGA) is an ancillary transcription initiation complex which is highly conserved. The ADA1 (alteration/deficiency in activation 1, also called histone H2A functional interactor 1, HFI1) is a subunit in the core module of the SAGA protein complex. ADA1 plays an important role in plant growth and development as well as stress resistance. In this paper, we performed genome-wide identification of banana ADA1 gene family members based on banana genomic data, and analyzed the basic physicochemical properties, evolutionary relationships, selection pressure, promoter cis-acting elements, and its expression profiles under biotic and abiotic stresses. The results showed that there were 10, 6, and 7 family members in Musa acuminata, Musa balbisiana and Musa itinerans. The members were all unstable and hydrophilic proteins, and only contained the conservative SAGA-Tad1 domain. Both MaADA1 and MbADA1 have interactive relationship with Sgf11 (SAGA-associated factor 11) of core module in SAGA. Phylogenetic analysis revealed that banana ADA1 gene family members could be divided into 3 classes. The evolution of ADA1 gene family members was mostly influenced by purifying selection. There were large differences among the gene structure of banana ADA1 gene family members. ADA1 gene family members contained plenty of hormonal elements. MaADA1-1 may play a prominent role in the resistance of banana to cold stress, while MaADA1 may respond to the Panama disease of banana. In conclusion, this study suggested ADA1 gene family members are highly conserved in banana, and may respond to biotic and abiotic stress.
Musa/genetics* ; Phylogeny ; Fungal Proteins ; Cell Nucleus ; Histones ; Stress, Physiological/genetics*

Glutamate receptor-like (GLR) is an important class of Ca²⁺ channel proteins, playing important roles in plant growth and development as well as in response to biotic and abiotic stresses. In this paper, we performed genome-wide identification of banana GLR gene family based on banana genomic data. Moreover, we analyzed the basic physicochemical properties, gene structure, conserved motifs, promoter cis-acting elements, evolutionary relationships, and used real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) to verify the expression patterns of some GLR family members under low temperature of 4 ℃ and different hormone treatments. The results showed that there were 19 MaGLR family members in Musa acuminata, 16 MbGLR family members in Musa balbisiana and 14 MiGLR family members in Musa itinerans. Most of the members were stable proteins and had signal peptides, all of them had 3-6 transmembrane structures. Prediction of subcellular localization indicated that all of them were localized on the plasma membrane and irregularly distributed on the chromosome. Phylogenetic analysis revealed that banana GLRs could be divided into 3 subclades. The results of promoter cis-acting elements and transcription factor binding site prediction showed that there were multiple hormone- and stress-related response elements and 18 TFBS in banana GLR. RT-qPCR analysis showed that MaGLR1.1 and MaGLR3.5 responded positively to low temperature stress and were significantly expressed in abscisic acid/methyl jasmonate treatments. In conclusion, the results of this study suggest that GLR, a highly conserved family of ion channels, may play an important role in the growth and development process and stress resistance of banana.
Musa/metabolism* ; Phylogeny ; Abscisic Acid/metabolism* ; Temperature ; Stress, Physiological/genetics* ; Hormones/metabolism* ; Gene Expression Regulation, Plant ; Plant Proteins/metabolism* ; Gene Expression Profiling

The epitranscriptomic mark N⁶-methyladenosine (m⁶A), which is the predominant internal modification in RNA, is important for plant responses to diverse stresses. Multiple environmental stresses caused by the tea-withering process can greatly influence the accumulation of specialized metabolites and the formation of tea flavor. However, the effects of the m⁶A-mediated regulatory mechanism on flavor-related metabolic pathways in tea leaves remain relatively uncharacterized. We performed an integrated RNA methylome and transcriptome analysis to explore the m⁶A-mediated regulatory mechanism and its effects on flavonoid and terpenoid metabolism in tea (Camellia sinensis) leaves under solar-withering conditions. Dynamic changes in global m⁶A level in tea leaves were mainly controlled by two m⁶A erasers (CsALKBH4A and CsALKBH4B) during solar-withering treatments. Differentially methylated peak-associated genes following solar-withering treatments with different shading rates were assigned to terpenoid biosynthesis and spliceosome pathways. Further analyses indicated that CsALKBH4-driven RNA demethylation can directly affect the accumulation of volatile terpenoids by mediating the stability and abundance of terpenoid biosynthesis-related transcripts and also indirectly influence the flavonoid, catechin, and theaflavin contents by triggering alternative splicing-mediated regulation. Our findings revealed a novel layer of epitranscriptomic gene regulation in tea flavor-related metabolic pathways and established a link between the m⁶A-mediated regulatory mechanism and the formation of tea flavor under solar-withering conditions.
RNA/metabolism* ; Epigenome ; Plant Proteins/metabolism* ; Plant Leaves/metabolism* ; Camellia sinensis/metabolism* ; Flavonoids ; Terpenes/metabolism* ; Tea/metabolism* ; Gene Expression Regulation, Plant

Oolong tea is a semi-fermented tea with strong flavor, which is widely favored by consumers because of its floral and fruity aroma as well as fresh and mellow taste. During the processing of oolong tea, withering is the first indispensable process for improving flavor formation. However, the molecular mechanism that affects the flavor formation of oolong tea during withering remains unclear. Transcriptome sequencing was used to analyze the difference among the fresh leaves, indoor-withered leaves and solar-withered leaves of oolong tea. A total of 10 793 differentially expressed genes were identified from the three samples. KEGG enrichment analysis showed that the differentially expressed genes were mainly involved in flavonoid synthesis, terpenoid synthesis, plant hormone signal transduction and spliceosome pathways. Subsequently, twelve differentially expressed genes and four differential splicing genes were identified from the four enrichment pathways for fluorescence quantitative PCR analysis. The results showed that the expression patterns of the selected genes during withering were consistent with the results in the transcriptome datasets. Further analysis revealed that the transcriptional inhibition of flavonoid biosynthesis-related genes, the transcriptional enhancement of terpenoid biosynthesis-related genes, as well as the jasmonic acid signal transduction and the alternative splicing mechanism jointly contributed to the flavor formation of high floral and fruity aroma and low bitterness in solar-withered leaves. The results may facilitate better understanding the molecular mechanisms of solar-withering treatment in flavor formation of oolong tea.
Camellia sinensis/genetics* ; Gene Expression Profiling ; Plant Leaves ; Plant Proteins/metabolism* ; Taste ; Tea ; Transcriptome/genetics*

Carotenoid cleavage dioxygenase (CCD) family is important for production of volatile aromatic compounds and synthesis of plant hormones. To explore the biological functions and gene expression patterns of CsCCD gene family in tea plant, genome-wide identification of CsCCD gene family was performed. The gene structures, conserved motifs, chromosome locations, protein physicochemical properties, evolutionary characteristics, interaction network and cis-acting regulatory elements were predicted and analyzed. Real time-quantitative reverse transcription PCR (RT-qPCR) was used to detect the relative expression level of CsCCD gene family members under different leaf positions and light treatments during processing. A total of 11 CsCCD gene family members, each containing exons ranging from 1 to 11 and introns ranging from 0 to 10, were identified. The average number of amino acids and molecular weight were 519 aa and 57 643.35 Da, respectively. Phylogenetic analysis showed the CsCCD gene family was clustered into 5 major groups (CCD1, CCD4, CCD7, CCD8 and NCED). The CsCCD gene family mainly contained stress response elements, hormone response elements, light response elements and multi-factor response elements, and light response elements was the most abundant (142 elements). Expression analysis showed that the expression levels of CsCCD1 and CsCCD4 in elder leaves were higher than those in younger leaves and stems. With the increase of turning over times, the expression levels of CsCCD1 and CsCCD4 decreased, while supplementary LED light strongly promoted their expression levels in the early stage. The expression level of NCED in younger leaves was higher than that in elder leaves and stems on average, and the expression trend varied in the process of turning over. NCED3 first increased and then decreased, with an expression level 15 times higher than that in fresh leaves. In the late stage of turning over, supplementary LED light significantly promoted its gene expression. In conclusion, CsCCD gene family member expressions were regulated by mechanical force and light. These understandings may help to optimize tea processing techniques and improve tea quality.
Camellia sinensis/genetics* ; Gene Expression Regulation, Plant ; Phylogeny ; Plant Leaves/genetics* ; Plant Proteins/metabolism* ; Tea