Plant Gene最新文献

Hydrogen peroxide, salicylic acid (SA) and jasmonic acid (JA) are reported to play important role in plant defense responses against pathogens. In this study, we analyzed the transcript abundance of oil palm respiratory burst oxidase B (EgRbohB1) and H (EgRbohH), Coronatine Insensitive 1 (EgCOI1), OPR5 (EgOPR5), hypersensitive induced response 1 (EgHIR1) and Nonexpressor of pathogenesis-related (EgNPR1) in Ganoderma boninense-inoculated oil palm roots that were pretreated with SA, JA and their inhibitors, paclobutrazol (PAC) and diethyldithiocarbamate (DIECA), respectively. We showed that EgNPR1 was down-regulated by G. boninense infection in SA-pretreated oil palm roots while EgHIR1 was up-regulated by G. boninense in PAC-pretreated oil palm roots. G. boninense inoculation did not change the gene expression levels of EgOPR5 in JA- and DIECA-treated oil palm roots significantly, compared to the uninoculated oil palms roots that were treated similarly. EgCOI1 was up-regulated by G. boninense in JA- and DIECA-pretreated oil palm roots, respectively. G. boninense up-regulated EgRbohB1 in SA-pretreated oil palm roots but down-regulated it in PAC-pretreated oil palm roots. EgRbohH was also down-regulated by G. boninense in PAC-pretreated oil palm roots. These findings facilitate the understanding of phytohormone effects on oil palm-Ganoderma interaction.

NUCLEOPORIN1 (NUP1), a component of the nuclear pore complex and an anchor for the TREX-2 mRNA export complex, was previously reported to have diverse functions in Arabidopsis. Several studies have shown that mutations in NUP1 lead to small stature plants with small leaves; however, the underlying mechanism is unknown. Here, we investigated the small leaf phenotype of nup1–1 plants and found that cell number and size are reduced. Next, gene expression analysis revealed significant changes in the expression of several cell-cycle and expansion-related genes in leaves of nup1–1 plants compared to the wild-type control (Col-0). Furthermore, the subcellular localization of NUP1 throughout mitosis uncovered the potential role of NUP1 in aligning the chromosome during metaphase and separation of chromosomes in anaphase. Our findings suggest that NUP1 is required for maintaining normal plant stature by regulating cell size and number. Further protein-protein interaction of NUP1 and metaphase-anaphase-related proteins would help identify the precise roles of NUP1 in cell division.

Gene duplication is a drive for genetic complexity and diversity, and can occur by several mechanisms. The plant phenotypic evolution is assumed to have been aided by whole-genome duplication. WGD (Whole genome duplication) events are often separated by tens of millions of years, resulting in a lack of a constant supply of variations for adaptation to ever-changing environments. Sweet cherry is a major Rosaceae fruit crop, however, it's uncertain whether distinct forms of gene duplications throughout evolution in sweet cherry where whole genome has been duplicated. In this study, genes were identified that derived from transposed, tandem, whole-genome, dispersed and proximal duplication events and differ in abundance, selection pressures, uninterrupted genes, expression divergence, as well as Go ontology enrichment analysis, and duplicate gene evolution were investigated using integrated large-scale genome and transcriptome datasets. The proximal and tandem mode of duplication expressed extreme conserve expression along with slow divergence, while transposed genes show higher regulatory divergence expression than other modes of duplication. We also examined at the development and expansion of gene families involved in the sugar metabolism pathways and organic acid, which are associated to the flavour and quality of sweet cherry fruit. The current study provides knowledge on the evolutionary fate and consequences of duplicate genes, providing the groundwork for future research into the dynamic evolution of duplicate genes.

Cotton fiber morphogenesis is tightly regulated by several microRNAs (miRNAs) including miR167 which regulates auxin-signaling through the transcriptional regulation of its target genes during fiber development. To emphasize the evolution of spatiotemporal regulatory attributes of miR167 genes during fiber development, a comparative analysis of 5′cis-regulatory elements (CREs) and coding sequences of miR167 genes from progenitor diploid A₂ (G. arboreum), D₅ (G. raimondii) species and decedent allopolyploid AD₁ (G. hirsutum) and AD₂ (G. barbadense) species were performed in an evolutionary framework. Interestingly, different miR167 genes were conserved both in A- and D-subgenomes of AD₁ and AD₂ species (>90% sequence similarities) and acquired the least variations in gene sequences during allopolyploidy followed by species diversification. However, substantial accumulation of structural variations in 1.5kb long upstream regions exhibited that the regulatory regions had undergone extensive evolutionary changes during cotton evolution in both diploid and allopolyploid species. Several unique CREs could be identified and further classified into development-, light-, organ-, stress- and hormone-responsive motifs with their varied frequencies. Co-expression analyses of miR167 genes and their respective CREs-binding transcription factors (TFs) showed tissue- and developmental stage-specific correlation, especially with bHLH transcription factor (R² = 0.93) during fiber initiation and elongation stages of AD₁ species. The reconstructed gene networks of the most significant predicted TFs with CREs underscored the possible genetic control mechanisms of these factors during fiber development. These observations highlighted that various regulatory motifs were preserved during cotton evolution and may be exploited for future crop improvement programs.

Toxic metabolites known as aflatoxins are produced via certain species of the Aspergillus genus, specifically A. flavus, A. parasiticus, A. nomius, and A. tamarie. Although various pre- and post-harvest strategies have been employed, aflatoxin contamination remains a major problem within peanut crop, especially in subtropical environments. Aflatoxins are the most well-known and researched mycotoxins produced within the Aspergillus genus (namely Aspergillus flavus) and are classified as group 1 carcinogens. Their effects and etiology have been extensively researched and aflatoxins are commonly linked to growth defects and liver diseases in humans and livestock. Despite the known importance of seed coats in plant defense against pathogens, peanut seed coat mediated defenses against Aspergillus flavus resistance, have not received considerable attention. The peanut seed coat (testa) is primarily composed of a complex cell wall matrix consisting of cellulose, lignin, hemicellulose, phenolic compounds, and structural proteins. Due to cell wall desiccation during seed coat maturation, postharvest A. flavus infection occurs without the pathogen encountering any active genetic resistance from the live cell(s) and the testa acts as a physical and biochemical barrier only against infection. The structure of peanut seed coat cell walls and the presence of polyphenolic compounds have been reported to inhibit the growth of A. flavus and aflatoxin contamination; however, there is no comprehensive information available on peanut seed coat mediated resistance. We have recently reviewed various plant breeding, genomic, and molecular mechanisms, and management practices for reducing A. flavus infection and aflatoxin contamination. Further, we have also proved that seed coat acts as a physical and biochemical barrier against A. flavus infection. The current review focuses specifically on the peanut seed coat cell wall-mediated disease resistance, which will enable researchers to understand the mechanism and design efficient strategies for seed coat cell wall-mediated resistance against A. flavus infection and aflatoxin contamination.