Rht-B1c, allelic to the DELLA protein-encoding gene Rht-B1a, is a natural mutation documented in common wheat (Triticum aestivum). It confers variation to a number of traits related to cell and plant morphology, seed dormancy, and photosynthesis. The present study was conducted to examine the sequence variations of Rht-B1c and their functional impacts. The results showed that Rht-B1c was partially dominant or co-dominant for plant height, and exhibited an increased dwarfing effect. At the sequence level, Rht-B1c differed from Rht-B1a by one 2kb Veju retrotransposon insertion, three coding region single nucleotide polymorphisms (SNPs), one 197bp insertion, and four SNPs in the 1kb upstream sequence. Haplotype investigations, association analyses, transient expression assays, and expression profiling showed that the Veju insertion was primarily responsible for the extreme dwarfing effect. It was found that the Veju insertion changed processing of the Rht-B1c transcripts and resulted in DELLA motif primary structure disruption. Expression assays showed that Rht-B1c caused reduction of total Rht-1 transcript levels, and up-regulation of GATA-like transcription factors and genes positively regulated by these factors, suggesting that one way in which Rht-1 proteins affect plant growth and development is through GATA-like transcription factor regulation.

No abstract

Wu (2020) Comparative transcriptome analyses of a table grape 'Summer Black' and its earlyripening mutant 'Tiangong Moyu' identify candidate genes potentially involved in berry development and ripening,

Necrosis and ethylene-inducing peptide 1 (Nep1) -like proteins (NLP) are secreted by multiple taxonomically unrelated plant pathogens (bacteria, fungi, and oomycete) and are best known for inducing cell death and immune responses in dicotyledonous plants. A group of putative NLP genes from obligate biotrophic oomycete Plasmopara viticola were predicted by RNA-Seq in our previous study, but their activity has not been established. Therefore, we analyzed the P. viticola NLP ( PvNLP ) family and identified seven PvNLP genes. They all belong to type 1 NLP genes and form a P. viticola -specific cluster when compared with other pathogen NLP genes. The expression of PvNLPs was induced during early infection process and the expression patterns could be categorized into two groups. Agrobacterium tumefaciens -mediated transient expression assays revealed that only PvNLP7 was cytotoxic and could induce Phytophthora capsici resistance in Nicotiana benthamiana . Functional analysis showed that PvNLP4, PvNLP5, PvNLP7, and PvNLP10 significantly improved disease resistance of Arabidopsis thaliana to Hyaloperonospora arabidopsidis . Moreover, the four genes caused an inhibition of plant growth which is typically associated with enhanced immunity when over-expressed in Arabidopsis. Further research found that PvNLP7 could activate the expression of defense-related genes and its conserved NPP1 domain was critical for cell death- and immunity-inducing activity. This record of NLP genes from P. viticola showed a functional diversification, laying a foundation for further study on pathogenic mechanism of the devastating pathogen.

The UFD1 protein is an important ubiquitin recognition component in the ubiquitin-mediated degradation pathway. To investigate the conservation of UFD1 genes among eukaryotes and their differentiation, two UFD1 paralogs from wheat were identified and mapped to homoeologous chromosome groups 6 and 2, respectively. TaUFD1a-6B and TaUFD1b-2D were cloned, and both genes consist of eight introns and of the same intron phases. These genes were compared with those in Arabidopsis, rice, polar, yeast, and mammals for their sequence, chromosome organization, and primary protein structure. The sequence structure, especially those corresponding to the fourth, fifth, and sixth exons of UFD1 genes, is highly conserved across these taxa. However, unlike yeast and mammals having a single UFD1 gene, higher angiosperm species have two ancient UFD1 paralogs. Besides the evolutionarily conserved ubiquitin-binding domain at the N-terminus, plant UFD1 proteins have three conserved C-terminal motifs. Motif I, near the UFD1 domain, displays a high level of similarity to the mammalian p97-binding site, and motif III is likely responsible for endoplasmic reticulum membrane retention. TaUFD1a-6B and TaUFD1b-2D are ubiquitously expressed in different plant tissues. A green fluorescent protein-transient expression assay in epidermal cells of onion demonstrated that TaUFD1 proteins primarily accumulate in the nucleus.

Grapevine (Vitis vinifera) is widely applicated in food industry, which shows high economical and nutritional values. However, growth of grapevine was usually affected by various environmental stresses, such as salt, drought and disease. Ubiquitin fusion degradation protein 1 (UFD1) is an essential ubiquitin-recognition protein facilitates regulation of stress response through ERAD pathway. Even though, a comprehensive investigation of UFD1 genes in the plant species is still lacking. Here we identified three VvUFD1 proteins from genome of grapevine, which were assigned into different subgroups. All VvUFD1 genes contain highly conserved motifs in structure. Several cis-elements that related to fruit development and stress response were found in the promoter regions of VvUFD1 genes, including bHLH, NCA, MYB, HD-ZIP, GATA and AP2. Expression analysis found VvUFD1 genes showed different expression patterns in different tissues. Most importantly, VvUFD1 genes were found to be involved in salt stress response during growth of grapevine. Transcriptomic analyses were investigated for further understanding the genes’ function. Expression of VvUFD1 were increased at late stage of berry ripening. In addition, expression of VvUFD1 were also regulated by elevated light treatment and pathogen Neofusicoccum parvum infection. Co-expression network analysis revealed several major transcription factors that co-expressed with VvUFD1 genes. These results provide a basis for investigating the function of UFD1 genes in plant species and expand understanding of the regulation of berry development and salt stress response in grapevine.

No abstract

Vitis champinii is a grapevine rootstock species and widely used in vineyards and in rootstock breeding programs for regions with high nematode populations or saline soils. Here, the complete chloroplast genome of V. champinii was reported. The length of the chloroplast genome was 160,657 bp with a large single copy region of 89,217 bp, a small single copy region of 19,504 bp and two separated inverted regions of 51,936 bp, respectively. In total, 130 unique genes were identified of this genome, including 85 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Phylogenetic analysis indicates that V. champinii is closely related to Vitis acerifolia.