Regulation of fruit ripening

AbstractLight plays a critical role in plant growth and development, but the mechanisms through which light regulates fruit ripening and nutritional quality in horticultural crops remain largely unknown. Here, we found that ELONGATED HYPOCOTYL 5 (HY5), a master regulator in the light signaling pathway, is required for normal fruit ripening in tomato (Solanum lycopersicum). Loss of function of tomato HY5 (SlHY5) impairs pigment accumulation and ethylene biosynthesis. Transcriptome profiling identified 2948 differentially expressed genes, which included 1424 downregulated and 1524 upregulated genes, in the Slhy5 mutants. In addition, genes involved in carotenoid and anthocyanin biosynthesis and ethylene signaling were revealed as direct targets of SlHY5 by chromatin immunoprecipitation. Surprisingly, the expression of a large proportion of genes encoding ribosomal proteins was downregulated in the Slhy5 mutants, and this downregulation pattern was accompanied by a decrease in the abundance of ribosomal proteins. Further analysis demonstrated that SlHY5 affected the translation efficiency of numerous ripening-related genes. These data indicate that SlHY5 regulates fruit ripening both at the transcriptional level by targeting specific molecular pathways and at the translational level by affecting the protein translation machinery. Our findings unravel the regulatory mechanisms of SlHY5 in controlling fruit ripening and nutritional quality and uncover the multifaceted regulation of gene expression by transcription factors.

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Genome-wide identification and analysis of the MADS-box gene family and its potential role in fruit ripening in black raspberry (Rubus occidentalis L.)

Journal of Berry Research ◽

10.3233/jbr-200679 ◽

2021 ◽

pp. 1-15

Author(s):

Yaqiong Wu ◽

Chunhong Zhang ◽

Wenlong Wu ◽

Weilin Li ◽

Lianfei Lyu

Keyword(s):

Gene Family ◽

Fruit Ripening ◽

Fruit Development ◽

Expression Patterns ◽

Type I ◽

Black Raspberry ◽

Mads Box ◽

Mads Box Genes ◽

Genome Wide ◽

Mads Box Gene

BACKGROUND: Black raspberry is a vital fruit crop with a high antioxidant function. MADS-box genes play an important role in the regulation of fruit development in angiosperms. OBJECTIVE: To understand the regulatory role of the MADS-box family, a total of 80 MADS-box genes were identified and analyzed. METHODS: The MADS-box genes in the black raspberry genome were analyzed using bioinformatics methods. Through an analysis of the promoter elements, the possible functions of different members of the family were predicted. The spatiotemporal expression patterns of members of the MADS-box family during black raspberry fruit development and ripening were systematically analyzed. RESULTS: The genes were classified into type I (Mα: 33; Mβ: 6; Mγ: 10) and type II (MIKC *: 2; MIKCC: 29) genes. We also obtained a complete overview of the RoMADS-box gene family through phylogenetic, gene structure, conserved motif, and cis element analyses. The relative expression analysis showed different expression patterns, and most RoMADS-box genes were more highly expressed in fruit than in other tissues of black raspberry. CONCLUSIONS: This finding indicates that the MADS-box gene family is involved in the regulation of fruit ripening processes in black raspberry.

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Sweet Pepper (Capsicum annuum L.) Fruits Contain an Atypical Peroxisomal Catalase That Is Modulated by Reactive Oxygen and Nitrogen Species

Antioxidants ◽

10.3390/antiox8090374 ◽

2019 ◽

Vol 8 (9) ◽

pp. 374 ◽

Cited By ~ 12

Author(s):

Marta Rodríguez-Ruiz ◽

Salvador González-Gordo ◽

Amanda Cañas ◽

María Jesús Campos ◽

Alberto Paradela ◽

...

Keyword(s):

Capsicum Annuum ◽

Fruit Ripening ◽

Reactive Oxygen ◽

Bovine Liver ◽

Sweet Pepper ◽

Cysteine Residue ◽

Nitrogen Species ◽

Capsicum Annuum L ◽

Native Molecular Mass ◽

Pepper Fruit

During the ripening of sweet pepper (Capsicum annuum L.) fruits, in a genetically controlled scenario, enormous metabolic changes occur that affect the physiology of most cell compartments. Peroxisomal catalase gene expression decreases after pepper fruit ripening, while the enzyme is also susceptible to undergo post-translational modifications (nitration, S-nitrosation, and oxidation) promoted by reactive oxygen and nitrogen species (ROS/RNS). Unlike most plant catalases, the pepper fruit enzyme acts as a homodimer, with an atypical native molecular mass of 125 to 135 kDa and an isoelectric point of 7.4, which is higher than that of most plant catalases. These data suggest that ROS/RNS could be essential to modulate the role of catalase in maintaining basic cellular peroxisomal functions during pepper fruit ripening when nitro-oxidative stress occurs. Using catalase from bovine liver as a model and biotin-switch labeling, in-gel trypsin digestion, and nanoliquid chromatography coupled with mass spectrometry, it was found that Cys377 from the bovine enzyme could potentially undergo S-nitrosation. To our knowledge, this is the first report of a cysteine residue from catalase that can be post-translationally modified by S-nitrosation, which makes it especially important to find the target points where the enzyme can be modulated under either physiological or adverse conditions.

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