Plant Molecular Biology最新文献

Cyclic nucleotide-gated channels (CNGCs) are evolutionarily conserved calcium-permeable non-selective cation channels that play critical regulatory roles in plant abiotic stress responses. This study characterizes HcCNGC11 in kenaf (Hibiscus cannabinus L.) through integrated genomic and functional analyses. Subcellular localization analysis using GFP-fusion constructs confirmed plasma membrane-specific targeting of HcCNGC11. Tissue-specific expression profiling revealed that HcCNGC11 transcripts accumulate predominantly in roots (2.8-fold higher than leaves), followed by leaves, stems, flowers, and seeds. Notably, HcCNGC11 demonstrated rapid transcriptional upregulation under 150 mM NaCl stress, reaching maximum induction at 3 h post-treatment. Virus-induced gene silencing of HcCNGC11 significantly inhibited kenaf growth under salt stress. Biochemical analyses of the silenced lines showed 5-66% reduced activities of antioxidant enzymes (SOD, POD, CAT), decreased osmoregulatory substances (soluble protein, proline), reduced chlorophyll content, and elevated ROS (H₂O₂, O₂·⁻) accumulation. Under salt stress, HcCNGC11-silenced plants displayed significant downregulation of antioxidant enzyme genes (HcSOD, HcPOD, HcCAT) as well as stress-responsive genes (HcP5CS, HcLTP, HcNCED). Conversely, Arabidopsis lines overexpressing HcCNGC11 exhibited 20-47% higher antioxidant enzyme activities, increased osmoregulatory substances, enhanced chlorophyll content, and markedly reduced ROS accumulation compared to WT under salt stress. Molecular analysis of these transgenic lines showed upregulated expression of antioxidant genes (AtSOD1, AtPOD1, AtCAT1) and stress-responsive genes (AtSOS1, AtNHX1, AtCOR15). Protein-protein interaction studies, employing both yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays, identified multiple HcCNGC11 binding partners, including HcCaM7, HcCNGC21, HcTHI1, and HcTCP14. Collectively, these results demonstrate that HcCNGC11 positively regulates plant salt tolerance through modulation of antioxidant systems and stress-responsive pathways.

Exploring the genetic landscape and corresponding regulatory mechanisms influencing morphine and related alkaloid production efficiency in the opium poppy (Papaver Somniferum L.) is important for sustainable medicinal production. However, information regarding the corresponding medicinal properties of poppy subspecies remains elusive, and the correlation between agronomic traits and morphine production remains unclear. this study aims to investigate the distinction between two poppy subspecies: Shan Yang (SY) and Lan Tian (LT). Physiological data revealed that SY exhibited greater tolerance to environmental stress and a higher morphine content than LT, especially during the reproductive stage. To investigate genetic and molecular mechanisms underlying different tolerance traits and morphine synthesis efficiencies, a comprehensive comparison of genomic, transcriptomic, and metabolomic data was conducted.The results showing significantly higher single nucleotide polymorphism (SNP) frequency in SY (23.78%) compared to LT (23.69%). The proportions of SKIP (Skipped Exon) and MIR (Multi Intron Retention) were higher in SY than in LT. SY showed significantly higher gene expression related to benzylisoquinoline alkaloid synthesis, especially those involved in the steps from 1,2 dehydroreticulinium to morphine, narcotoline and noscapine, compared to LT. The upregulated expression of phenylpropanoid biosynthesis-related genes contributes to its more resistant agronomical traits. It plays a synergistic role in alkaloid production. The higher morphine content in SY resulted from an integrated effect controlled at different levels. Our findings offer new insights into the molecular mechanisms of morphine synthesis and present valuable gene resources for improving poppy cultivars with higher morphine content.