查看更多>>摘要：Numerous studies have been dedicated to genetically engineering crops to enhance their yield and quality.One of the key requirements for generating genetically modified plants is the reprogramming of cell fate.However,the efficiency of shoot regeneration during this process is highly dependent on genotypes,and the underlying molecular mechanisms remain poorly understood.Here,we identified microRNA396(miR396)as a negative regulator of shoot regeneration in tomato.By selecting two genotypes with contrasting shoot regeneration efficiencies and analyzing their transcriptome profiles,we found that miR396 and its target transcripts,which encode GROWTH-REGULATING FACTORs(GRFs),exhibit differential abundance between high-and low-efficiency genotypes.Suppression of miR396 functions significantly improved shoot regeneration rates along with increased expression of GRFs in transformed T0 explants,suggesting that miR396 is a key molecule involved in the determination of regeneration efficiency.Notably,we also showed that co-expression of a miR396 suppressor with the gene-editing tool can be employed to generate gene-edited plants in the genotype with a low capacity for shoot regeneration.Our findings show the critical role of miR396 as a molecular barrier to shoot regeneration in tomato and suggest that regeneration efficiency can be improved by blocking this single microRNA.
查看更多>>摘要：Wood quality is predominantly determined by the amount and the composition of secondary cell walls(SCWs).Consequently,unraveling the molecular regulatory mechanisms governing SCW formation is of paramount importance for genetic engineering aimed at enhancing wood properties.Although SCW formation is known to be governed by a hierarchical gene regulatory network(HGRN),our understanding of how a HGRN operates and regulates the formation of heterogeneous SCWs for plant development and adaption to ever-changing environment remains limited.In this review,we examined the HGRNs governing SCW formation and highlighted the significant key differences between herbaceous Arabidopsis and woody plant poplar.We clarified many confusions in existing literatures regarding the HGRNs and their orthologous gene names and functions.Additionally,we revealed many network motifs including feed-forward loops,feed-back loops,and negative and positive autoregulation in the HGRNs.We also conducted a thorough review of post-transcriptional and post-translational aspects,protein-protein interactions,and epigenetic modifications of the HGRNs.Furthermore,we summarized how the HGRNs respond to environmental factors and cues,influencing SCW biosynthesis through regulatory cascades,including many regulatory chains,wiring regulations,and network motifs.Finally,we highlighted the future research directions for gaining a further understanding of molecular regulatory mechanisms underlying SCW formation.
查看更多>>摘要：Artemisinin,also known as'Qinghaosu',is a chemically sesquiterpene lactone containing an endoperoxide bridge.Due to the high activity to kill Plasmodium parasites,artemisinin and its derivatives have continuously served as the foundation for antimalarial therapies.Natural artemisinin is unique to the traditional Chinese medicinal plant Artemisia annua L.,and its content in this plant is low.This has motivated the synthesis of this bioactive compound using yeast,tobacco,and Physcomitrium patens systems.However,the artemisinin production in these heterologous hosts is low and cannot fulfil its increasing clinical demand.Therefore,A.annua plants remain the major source of this bioactive component.Recently,the transcriptional regulatory networks related to artemisinin biosynthesis and glandular trichome formation have been extensively studied in A.annua.Various strategies including(i)enhancing the metabolic flux in artemisinin biosynthetic pathway;(ii)blocking competition branch pathways;(iii)using transcription factors(TFs);(iv)increasing peltate glandular secretory trichome(GST)density;(v)applying exogenous factors;and(vi)phytohormones have been used to improve artemisinin yields.Here we summarize recent scientific advances and achievements in artemisinin metabolic engineering,and discuss prospects in the development of high-artemisinin yielding A.annua varieties.This review provides new insights into revealing the transcriptional regulatory networks of other high-value plant-derived natural compounds(e.g.,taxol,vinblastine,and camptothecin),as well as glandular trichome formation.It is also helpful for the researchers who intend to promote natural compounds production in other plants species.
NETL
NSTL
万方数据