RESUMEN
Chinese rose (Rosa chinensis) is an important ornamental plant, with economic, cultural, and symbolic significance. During the application of outdoor greening, adverse environments such as high temperature and drought are often encountered, which affect its application scope and ornamental quality. The starch phosphorylase (Pho) gene family participate in the synthesis and decomposition of starch, not only related to plant energy metabolism, but also plays an important role in plant stress resistance. The role of Pho in combating salinity and high temperature stress in R. chinensis remains unknown. In this work, 4 Phos from R. chinensis were detected with Pfam number of Pho (PF00343.23) and predicted by homolog-based prediction (HBP). The Phos are characterized by sequence lengths of 821 to 997 bp, and the proteins are predicted to subcellularly located in the plastid and cytoplasm. The regulatory regions of the Phos contain abundant stress and phytohormone-responsive cis-acting elements. Based on transcriptome analysis, the Phos were found to respond to abiotic stress factors such as drought, salinity, high temperature, and plant phytohormone of jasmonic acid and salicylic acid. The response of Phos to abiotic stress factors such as salinity and high temperature was confirmed by qRT-PCR analysis. To evaluate the genetic characteristics of Phos, a total of 69 Phos from 17 species were analyzed and then classified into 3 groups in phylogenetic tree. The collinearity analysis of Phos in R. chinensis and other species was conducted for the first time. This work provides a view of evolution for the Pho gene family and indicates that Phos play an important role in abiotic stress response of R. chinensis.
Asunto(s)
Regulación de la Expresión Génica de las Plantas , Familia de Multigenes , Filogenia , Rosa , Almidón Fosforilasa , Estrés Fisiológico , Estrés Fisiológico/genética , Rosa/genética , Rosa/enzimología , Rosa/metabolismo , Almidón Fosforilasa/genética , Almidón Fosforilasa/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilación de la Expresión Génica , Sequías , Genoma de Planta , SalinidadRESUMEN
The tuberous roots of Potentilla anserina (Pan) are an edible and medicinal resource in Qinghai-Tibetan Plateau, China. The triterpenoids from tuberous roots have shown promising anti-cancer, hepatoprotective, and anti-inflammatory properties. In this study, we carried out phylogenetic analysis of squalene synthases (SQSs), squalene epoxidases (SQEs), and oxidosqualene cyclases (OSCs) in the pathway of triterpenes. In total, 6, 26, and 20 genes of SQSs, SQEs, and OSCs were retrieved from the genome of Pan, respectively. Moreover, 6 SQSs and 25 SQEs genes expressed in two sub-genomes (A and B) of Pan. SQSs were not expanded after whole-genome duplication (WGD), and the duplicated genes were detected in SQEs. Twenty OSCs were divided into two clades of cycloartenol synthases (CASs) and ß-amyrin synthases (ß-ASs) by a phylogenetic tree, characterized with gene duplication and evolutionary divergence. We speculated that ß-ASs and CASs may participate in triterpenes synthesis. The data presented act as valuable references for future studies on the triterpene synthetic pathway of Pan.
Asunto(s)
Transferasas Intramoleculares , Potentilla , Triterpenos , Farnesil Difosfato Farnesil Transferasa/genética , Transferasas Intramoleculares/genética , Transferasas Intramoleculares/metabolismo , Filogenia , Potentilla/genética , Escualeno , Triterpenos/metabolismoRESUMEN
KEY MESSAGE: A major QTL controlling ovule abortion and SN was fine-mapped to a 80.1-kb region on A8 in rapeseed, and BnaA08g07940D and BnaA08g07950D are the most likely candidate genes. The seed number per silique (SN), an important yield determining trait of rapeseed, is the final consequence of a complex developmental process including ovule initiation and the subsequent ovule/seed development. To explore the genetic mechanism regulating the natural variation of SN and its related components, quantitative trait locus (QTL) mapping was conducted using a doubled haploid (DH) population derived from the cross between C4-146 and C4-58B, which showed significant differences in SN and aborted ovule number (AON), but no obvious differences in ovule number (ON). QTL analysis identified 19 consensus QTLs for six SN-related traits across three environments. A novel QTL on chromosome A8, un.A8, which associates with multiple traits, except for ON, was stably detected across the three environments. This QTL explained more than 50% of the SN, AON and percentage of aborted ovules (PAO) variations as well as a moderate contribution on silique length (SL) and thousand seed weight (TSW). The C4-146 allele at the locus increases SN and SL but decreases AON, PAO and TSW. Further fine mapping narrowed down this locus into an 80.1-kb interval flanked by markers BM1668 and BM1672, and six predicted genes were annotated in the delimited region. Expression analyses and DNA sequencing showed that two homologs of Arabidopsis photosystem I subunit F (BnaA08g07940D) and zinc transporter 10 precursor (BnaA08g07950D) were the most promising candidate genes underlying this locus. These results provide a solid basis for cloning un.A8 to reduce the ovule abortion and increase SN in the yield improvement of rapeseed.
Asunto(s)
Brassica napus/crecimiento & desarrollo , Mapeo Cromosómico/métodos , Cromosomas de las Plantas/genética , Regulación de la Expresión Génica de las Plantas , Óvulo Vegetal/fisiología , Proteínas de Plantas/metabolismo , Semillas/crecimiento & desarrollo , Brassica napus/genética , Clonación Molecular , Fenotipo , Proteínas de Plantas/genética , Semillas/genéticaRESUMEN
Yellow seed is a desirable trait with great potential for improving seed quality in Brassica crops. Unfortunately, no natural or induced yellow seed germplasms have been found in Brassica napus, an important oil crop, which likely reflects its genome complexity and the difficulty of the simultaneous random mutagenesis of multiple gene copies with functional redundancy. Here, we demonstrate the first application of CRISPR/Cas9 for creating yellow-seeded mutants in rapeseed. The targeted mutations of the BnTT8 gene were stably transmitted to successive generations, and a range of homozygous mutants with loss-of-function alleles of the target genes were obtained for phenotyping. The yellow-seeded phenotype could be recovered only in targeted mutants of both BnTT8 functional copies, indicating that the redundant roles of BnA09.TT8 and BnC09.TT8b are vital for seed colour. The BnTT8 double mutants produced seeds with elevated seed oil and protein content and altered fatty acid (FA) composition without any serious defects in the yield-related traits, making it a valuable resource for rapeseed breeding programmes. Chemical staining and histological analysis showed that the targeted mutations of BnTT8 completely blocked the proanthocyanidin (PA)-specific deposition in the seed coat. Further, transcriptomic profiling revealed that the targeted mutations of BnTT8 resulted in the broad suppression of phenylpropanoid/flavonoid biosynthesis genes, which indicated a much more complex molecular mechanism underlying seed colour formation in rapeseed than in Arabidopsis and other Brassica species. In addition, gene expression analysis revealed the possible mechanism through which BnTT8 altered the oil content and fatty acid composition in seeds.