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• The mechanism of CPPU promoting grape fruiting was elucidated from two aspects, energy metabolism and respiratory metabolism. • Establish the relationship between CPPU and energy. • It provides new insights for the study of 'Kyoho' grape berry setting. The energy status, the level of respiration metabolism are improtant index reflecting plant growth state, participates in many growth processes. However, their relationship to berry setting remain unclear. In this study, the grape of 'kyoho' of CPPU [CPPU, N-(2-coloro-4-pyridinyl)-N-phenylurea] treated were used to measurement physiological indicators. The results showed that CPPU treatment reduced respiratory rate, reduced Cytochrome C oxidase (CCO) and ascorbic acid oxidase (AAO) activity, reduced NAD kinase (NADK) activity, maintained low nicotinamide adenine denucleotie phosphate (NADP) and nicotinamide adenine denucleotie phosphate reduced form (NADPH) levels, reduced nicotinamide adenine denucleotie (NADH) levels, and slowed down the reduction of energy charge. These results provided strong evidence that CPPU treatment promoted grape berry setting due to increased energy status, increased Embden-Meyerhof pathway (EMP) and the tricarboxylic acid (TCA) cycle respiratory metabolic pathways, decreased pentose phosphate pathway (PPP), and decreased CCO and AAO activity of respiratory terminal oxidase. [ABSTRACT FROM AUTHOR]

• VvbZIP60 is constitutively expressed and can be induced by pathogens, SA, JA in grapes. • VvbZIP60 is localized in the nucleus and has transcriptional activation activity. • VvbZIP60 contributes to disease resistance and activation of SA pathway in Arabidopsis. Powdery mildew is a fungus that causes major losses in grape production worldwide. Recent studies demonstrate bZIP transcription factors (TFs) play an important role in plant defense against fungal pathogens. To investigate whether one or more bZIP TFs is involved in the common grapevine's defense against powdery mildew, which could provide candidate genes for breeding powdery mildew-resistant grape plants, we isolated its VvbZIP60 gene and analyzed its functional role in plants against powdery mildew. Amino acid sequence alignment and phylogenetic analysis indicated that VvbZIP60 is a U member of the bZIP gene family and is similar to AtbZIP60 of Arabidopsis. The gene expression profile of the 'Jing Xiu' variety of grape (Vitis vinifera) showed that the VvbZIP60 transcript accumulated in various tissues (especially leaves) and could quickly accumulate when this plant was treated with exogenous pathogen (PA), 1 1 Abbreviations: DAPI, 4',6-diamidino-2-phenylindole; GFP, green fluorescent protein; HPI, hours post-inoculation; JA, jasmonic acid; MeJA, methyl jasmonate; OE, overexpressing plants; PA, pathogen; PR1, pathogenesis related 1; PDF1.2, plant defensin 1.2; SA, salicylic acid; SAR, systemic acquired resistance; TFs, transcription factors; WT, wild type. salicylic acid (SA) and jasmonic acid (JA). VvbZIP60 was found localized to the nucleus and has transcriptional activation in yeast. Crucially, overexpression of VvbZIP60 increased Arabidopsis resistance to powdery mildew. Transgenic plants accumulated SA and up-regulated their expression of the pathogenesis related 1 (PR1) gene involved in the SA-signaling pathway. Taken together, these results show that VvbZIP60 is a positive regulator of resistance to fungal disease and contributes importantly to SA signaling against powdery mildew. [ABSTRACT FROM AUTHOR]

• Six genes are determined as proline biosynthesis- or proline catabolism-related genes in grapevines. • P5CS1, OAT, PDH and P5CDH can be significantly induced by osmotic and oxidative stresses. • Proline is greatly accumulated under abiotic stresses, especially osmotic and oxidative stresses. • Proline biosynthesis and proline catabolism-related genes synergistically regulate proline accumulation in response to abiotic stresses. Proline is an important osmotic regulator for plants under abiotic stresses. Proline accumulation is regulated by various enzymes, while genes encoding these enzymes have not been fully investigated in grapevines. In this study, we identified four proline biosynthesis-related genes (P5CS1, P5CS2, P5CR and OAT) and two proline catabolism-related genes (PDH and P5CDH) from grapevines, and conducted bioinformatics analysis including protein characteristic, gene structure, phylogenetic relationship and cis-acting element of promoters. Promoter analysis found that cis-acting elements related to stress and phytohormone responsiveness were present in the promoters of these genes. Tissue-specific expression analysis of these genes indicated that P5CS2, OAT and PDH expressed highly in flower, and P5CS1, P5CR and P5CDH had highest expression levels in tendril, berry and leaf respectively. Expression patterns of these genes under abiotic stresses revealed that P5CS1, OAT and PDH could be significantly induced by salt, dehydration, PEG and H 2 O 2 treatments, and P5CDH was significantly suppressed under these stress treatments. By measuring proline accumulation in grapevines, we found that proline content dramatically increased after treatments of salt, dehydration, PEG and H 2 O 2. Our results revealed the molecular responses (especially P5CS1, OAT, PDH and P5CDH) in the proline metabolism pathway to osmotic and oxidative stresses in grapevines, demonstrating that proline synthesis and proline catabolism synergistically regulate proline accumulation in response to abiotic stresses. [ABSTRACT FROM AUTHOR]

• Overexpression of VvZFP11 improves powdery mildew resistance in grapes. • The PME element of the VvZFP11 gene is essential for its function. • The VvZFP11 gene enables plants to acquire resistance by affecting the salicylic acid signaling pathway. VvZFP11 is up-regulated by powdery mildew (PM), methyl jasmonate (MeJA), and salicylic acid (SA) treatment, yet the underlying transcriptional regulatory mechanism remains unclear. Here, we demonstrate that a powdery mildew response element (PME) in the VvZFP11 promoter is important for countering the challenge to grapevine from PM, in which the defensive and stress response element (GTAAGGAAAC) is critical for specific responsiveness to SA, MeJA, and PM. Analysis of VvZFP11 promoter activity showed that VvZFP11 can activate GUS gene expression. SA induced VvZFP11 's expression, while VvZFP11 responded swiftly to PM. Analysis of cis- acting elements revealed that VvZFP11 contained diverse elements related to plant responses to biotic/abiotic stresses. Further experiments revealed PME in the VvZFP11 promoter was crucial for responding to PM. The PME and MV35S core promoters were fused and constructed into a single promoter, then inserted directionally into VvZFP11-GUS's upstream region to obtain a fusion construct. VvZFP11 transcript levels were significantly suppressed in transgenic plants with mutant PEM element after their inoculation with PM (based on Fig. 6). RT-qPCR results indicated the genes AtPR1, AtNPR1, AtPDF1.2 , and AtCOI , these related to SA and MeJA, were down-regulated in transgenic plants. The results also confirmed the defensive and stress response element in PME is a key component for the VvZFP11 promoter's function and that VvZFP11 enables plants to gain resistance to PM via the SA pathways. [ABSTRACT FROM AUTHOR]

• Transcriptome analysis shows the responsive pathways to K + deficiency in grapevines. • Ethylene signal (especially ERFs) are activated after K + deficiency. • Cell wall biosynthesis in roots is inhibited after K + deficiency. • Photosynthesis in shoots is inhibited after K + deficiency. • Ion transporters are induced by K + deficiency. Grapevine is sensitive to potassium (K +) deficiency, while its underlying responsive mechanisms are unknown. In this study, transcriptome profiling of grapevine seedlings under K + deficiency conditions over a time course were investigated. Morphological measurements showed that K + deficiency inhibited the normal growth of grapevine seedlings. RNA-sequencing (RNA-seq) was performed with samples of roots and shoots collected under K + deficiency and normal conditions, and numerous differentially expressed genes (DEGs) induced by K + deficiency were identified, including some ion transporter genes, ethylene-responsive transcription factor (ERF) genes, and cell wall biosynthesis-related genes. In roots, by functional and regulatory pathway analysis, genes in ethylene signal (especially ERF) and in cell wall biosynthesis pathway were upregulated and downregulated, respectively, indicating that ethylene signal was activated, while cell wall biosynthesis was inhibited under K + deficiency treatment. And in shoots, genes in ethylene signal and in photosynthesis pathway were upregulated and downregulated, respectively, revealing that ethylene signal was activated, while photosynthesis was suppressed under K + deficiency treatment. Analysis of transcription factors indicated that ERF family extensively involved in the response to K + deficiency. Taken together, this study reveals the multiple molecular responses, including ethylene signal, ion homeostasis, and other metabolic pathways, to K + deficiency treatment in grapevines. [ABSTRACT FROM AUTHOR]