查看更多>>摘要：Houttuynia cordata Thunb.,commonly known as yuxingcao in China,is known for its characteristic fishy smell and is widely recognized as an important herb and vegetable in many parts of Asia.However,the lack of genomic information on H.cordata limits the understanding of its population structure,genetic diversity,and biosynthesis of medicinal compounds.Here we used single-molecule sequencing,Illumina paired-end sequencing,and chromosome conformation capture technology to construct the first chromosome-scale decaploid H.cordata reference genome.The genome assembly was 2.63 Gb in size,with 1348 contigs and a contig N50 of 21.94 Mb further clustered and ordered into 88 pseudochromosomes based on Hi-C analysis.The results of genome evolution analysis showed that H.cordata underwent a whole-genome duplication(WGD)event～17 million years ago,and an additional WGD event occurred 3.3 million years ago,which may be the main factor leading to the high abundance of multiple copies of orthologous genes.Here,transcriptome sequencing across five different tissues revealed significant expansion and distinct expression patterns of key gene families,such as L-amino acid/L-tryptophan decarboxylase and strictosidine synthase,which are essential for the biosynthesis of isoquinoline and indole alkaloids,along with the identification of genes such as TTM3,which is critical for root development.This study constructed the first decaploid medicinal plant genome and revealed the genome evolution and polyploidization events of H.cordata.
查看更多>>摘要：Root-knot nematodes(Meloidogyne spp.)are widely spread root parasites that infect thousands of vascular plant species.These highly polyphagous nematodes engage in sophisticated interactions with host plants that results in the formation of knot-like structures known as galls whose ontogeny remains largely unknown.Here,we determined transcriptome changes and alternative splicing variants induced by Megalaima incognita in galls and neighboring root cells at two distinct infective stages.M.incognita induced substantial transcriptome changes in tomato roots both locally in galls and systemically in neighboring cells.A considerable parallel regulation of gene expression in galls and neighboring cells were detected,indicative of effective intercellular communications exemplified by suppression of basal defense responses particularly during the early stage of infection.The transcriptome analysis also revealed that M.incognita exerts a tight control over the cell cycle process as a whole that results in an increase of ploidy levels in the feeding sites and accelerated mitotic activity of the gall cells.Alternative splicing analysis indicated that M.incognita significantly modulates pre-mRNA splicing as a total of 9064 differentially spliced events from 2898 genes were identified where intron retention and exon skipping events were largely suppressed.Furthermore,a number of differentially spliced events were functionally validated using transgenic hairy root system and found to impact gall formation and nematode egg mass production.Together,our data provide unprecedented insights into the transcriptome and spliceome reprogramming induced by M.incognita in tomato with respect to gall ontogeny and nematode parasitism.
查看更多>>摘要：Grapevine(Vitis vinifera L.,)is among the world's leading fruit crops.The production of grapes is severely affected by many diseases including gray mold,caused by the necrotrophic fungus Botrytis cinerea.Although all Vitis species can be hosts for B.cinerea,V.vinifera are particularly susceptible.Accordingly,this disease poses a significant threat to the grape industry and causes substantial economic losses.Development of resistant V.vinifera cultivars has progressed from incidental selection by farmers,to targeted selection through the use of statistics and experimental design,to the employment of genetic and genomic data.Emerging technologies such as marker-assisted selection and genetic engineering have facilitated the development of cultivars that possess resistance to B.cinerea.A promising method involves using the CRISPR/Cas9 system to induce targeted mutagenesis and develop genetically modified non-transgenic crops.Hence,scientists are now engaged in the active pursuit of identifying genes associated with susceptibility and resistance.This review focuses on the known mechanisms of interaction between the B.cinerea pathogen and its grapevine host.It also explores innate immune systems that have evolved in V.vinifera,with the objective of facilitating the rapid development of resistant grapevine cultivars.
查看更多>>摘要：Low-temperature storage is used to extend the shelf life of fruits,but prolonged storage at temperatures below tolerable levels may cause postharvest chilling injury(PCI)in sensitive commodities.This review aims to highlight adenosine triphosphate(ATP)activation and the interplay of extracellular ATP(eATP)and intracellular ATP(iATP)in fruits and to find out its significance in mitigating PCI.Various pathways,such as the Embden-Meyerhof-Parnas pathway,the tricarboxylic acid cycle,the pentose phosphate pathway,the y-aminobutyric acid shunt pathway,and the cytochrome pathway,are studied critically to elucidate their role in continuous ATP supply and maintaining the membrane fluidity and integrity.This review summarizes the treatments helpful in modulating energy metabolism in fruit.Additionally,this work provides insights into the energy status in attenuating chilling tolerance.Moreover,it states the potential of nicotinamide adenine dinucleotide in mitigating PCI.Furthermore,it discusses the role of eATP and its receptor DORN1 in mitigating chilling stress.
查看更多>>摘要：Our knowledge of crop domestication,genomics,and of the plant virosphere unevenly represents the taxonomic distribution of the global biodiversity,and,as we show here,is significantly enriched for the Solanaceae.Within the family,potato,tomato,eggplant,pepper,and over 100 lesser-known edible species play important nutrition and cultural roles in global and local food systems.Technologies using engineered viruses are transitioning from proof-of-concept applications in model plants to the precise trait breeding of Solanaceae crops.Leveraging this accumulated knowledge,we highlight the potential of virus-based biotechnologies for fast-track improvement of Solanaceae crop production systems,contributing to enhanced global and local human nutrition and food security.
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