Plant Molecular Biology最新文献

The robust growth of grape shoots often results in diminished grape quality and increased labor costs in grape production. Investigating the patterns of shoot elongation and the underlying mechanisms is beneficial for simplifying cultivation processes and enhancing fruit quality. However, there is limited research on this topic. In this study, we found that lateral growth and elongation growth occurred simultaneously in each grape internode, and exhibited a similar sigmoid growth curve model. The dissection of the internode structure revealed that elongation of the cells in the middle of the stem was the primary reason for the rapid elongation of grape shoots, while the sharp increase in the xylem area significantly contributed to the lateral growth of the internodes. Transcriptome analysis indicated that genes associated with cell cycle organization, cell wall organization, and phytohormone activity play important roles in regulating the growth of grape internodes. One candidate gene, VvSAUR72, which is related to auxin signaling components, was characterized to promote internode elongation by overexpression in Arabidopsis. These results provide a foundation for further investigation into the regulatory mechanisms related to the internode elongation in grapevine.

Plant architecture is one of the most important qualities of Platanus acerifolia Willd., enabling it to be known as "the king of street trees". However, there are few reports available on its molecular regulatory mechanisms. Shoot branching is a key process in regulating plant architecture. In this study, topping experiments and transcriptome sequencing analyses were performed to elucidate the molecular mechanisms underlying axillary bud growth and development in P. acerifolia. After 3 d of topping, the axillary buds in P. acerifolia exhibited significant growth, with the trend increasing over subsequent days. The KEGG enrichment analysis revealed considerable changes in the expression levels of genes involved in the auxin signal transduction pathway. Additionally, the expression of most PaSPL genes was downregulated after topping. While Pla-miR156f regulated Arabidopsis plant architecture, flowering transition and flower development, this regulation was not directly influenced by the topping pathway. These results contribute to a better understanding of P. acerifolia plant architecture regulation and provide valuable insights into the regulation of other plants, particularly woody plants.

Salinity is a major problem due to the continuous increase in the salinization of agricultural lands, particularly, paddy fields. Using a forward genetics approach, salt-insensitive TILLING line 3, sitl3, was selected from a core population induced by gamma-ray irradiation. Under salt stress, sitl3 had greater fresh weight and chlorophyll content, and lower H₂O₂ and Na⁺ contents than the wild-type. In the gene (LOC_Os07g46180) with two PWWP domains (named Oyza sativa PWWP4, OsPWWP4) of sitl3, a premature stop was caused by an SNP, and was named OsPWWP4p.Gly462* (a stop gain occurred from the 462th amino acid residue). The OsPWWP4 and substrate proteins (OsEULS2, OsEULS3, and OsEULD2) were identified using yeast two-hybrid, bimolecular fluorescence complementation, in vitro pull-down, and in vitro methyltransferase assays. Subcellular localization of OsPWWP4 and OsPWWP4p.Gly462*GFP-tagged proteins revealed they were both localized in the nucleus, while OsEULS2, OsEULS3, and OsEULD2 GFP-tagged proteins were found in the nucleus and cytosol of rice protoplasts. The expression levels of OsEULS2, OsEULS3, OsEULD2 under salt stress were higher in sitl3 than in wild-type plants. In contrast, OsPWWP4 expression was higher in the latter. Genes involved in the salt overly sensitive (SOS) pathway showed higher expression in the aerial tissues of silt3 than in the wild-type. CRISPR/Cas9-mediated OsPWWP4 knock-out transgenic plants showed salt tolerance phenotypes with low Na⁺ contents and low Na⁺/K⁺ ratios. The data suggest that sitl3 is a valuable genetic resource for understanding protein post-translational regulation-related salinity tolerance mechanisms such as methyltransferase activities, and for improving salt tolerance in rice through breeding.

The allotetraploid (AACC) was synthesized through wide hybridization between 'Mottle-leaf Tai-cai' (Brassica rapa var. tai-tsai Hort. AA) and 'Big Yellow Flower Chinese Kale' (B. oleracea var. alboglabra Bailey. CC) in earlier study, which owns a stronger wrinkled leaf and wave margin than Tai-cai. To analyze the structure and developmental mechanism of wrinkled leaf and wave edge, four leaf development stages were chosen for RNA-seq and their key stages for anatomical observation. As a result, the number of cell layers and compactness of AA and AACC were significantly increased in folded parts, and the enlargement of epidermal cells causes the leaf edge to curve inward. The gene expression bias of AACC showed no difference in the cotyledon stage, favored the A genome in the first leaf stage, however, favored the C genome in the third leaf and fifth leaf stages, showing an expression level advantage over the C genome parent. During the leaf development, the plant hormone signaling pathway were significantly enriched, PIN1 (BraC07g037600), AUX1 (BraC05g007870), AUX/IAA (BraC03g037630), and GH3 (BraC10g026970), which maintained high expression during the euphylla leaf stage of AA and AACC. And these genes performed different patterns in CC. In addition, the expression levels of miR319 and miR156 of AA were significantly higher than those of CC, and the expression levels of their target genes TCP and SPL were lower. These genes were jointly involved in the development of AA and AACC leaves and may be closely related to the formation of leaf folds and waves.

Light is a critical environmental factor that governs the growth and development of plants. Plants have specialised photoreceptor proteins, which allow them to sense both quality and quantity of light and drive a wide range of responses critical for optimising growth, resource use and adaptation to changes in environment. Understanding the role of these photoreceptors in plant biology has opened up potential avenues for engineering crops with enhanced productivity by engineering photoreceptor activity and/or action. The ability to manipulate plant genomes through genetic engineering and synthetic biology approaches offers the potential to unlock new agricultural innovations by fine-tuning photoreceptors or photoreceptor pathways that control plant traits of agronomic significance. Additionally, optogenetic tools which allow for precise, light-triggered control of plant responses are emerging as powerful technologies for real-time manipulation of plant cellular responses. As these technologies continue to develop, the integration of photoreceptor engineering and optogenetics into crop breeding programs could potentially revolutionise how plant researchers tackle challenges of plant productivity. Here we provide an overview on the roles of key photoreceptors in regulating agronomically important traits, the current state of plant photoreceptor engineering, the emerging use of optogenetics and synthetic biology, and the practical considerations of applying these approaches to crop improvement. This review seeks to highlight both opportunities and challenges in harnessing photoreceptor engineering approaches for enhancing plant productivity. In this review, we provide an overview on the roles of key photoreceptors in regulating agronomically important traits, the current state of plant photoreceptor engineering, the emerging use of optogenetics and synthetic biology, and the practical considerations of applying these approaches to crop improvement.

Plants have developed two major strategies to adjust their position in response to gravity: differential cell growth on opposing sides of elongating regions and complex processes in non-elongating stem parts, such as the development of reaction wood. Gravistimulation of flax plants induces gravitropic curvature in non-elongating stem parts, largely associated with modifications in phloem and xylem fibers. To gain insight into the key "triggers" and "forward players" that induce negative gravitropic reactions, transcriptome profiling of phloem fibers and xylem tissues from the pulling and opposite stem sides was conducted 1 and 8 h after gravistimulation. The first observed reaction was the activation of processes associated with RNA synthesis and protein folding in both tissues and stem sides, followed by the activation of kinases and transferases. Transcriptomic data revealed rapid and substantial shifts in chloroplast metabolism across all analyzed tissues, including the temporal activation of the branched-chain amino acid pathway, adjustments to light-harvesting complexes, and jasmonic acid biosynthesis. Notably, auxin transporter genes were activated only in the xylem, while other auxin-related genes showed minimal upregulation 1 h after stem inclination in any analyzed sample. Asymmetric changes between stem sides included the sharp activation of ethylene-related genes in the phloem fibers of the opposite stem side, as well as tertiary cell wall deposition in both the phloem and xylem fibers of the pulling stem side during the later stages of the graviresponse. These results provide valuable insights into the mechanisms underlying plant response to gravity.

Exogenous hormones can regulate bud dormancy release, particularly in cases where inadequate winter chill accumulation due to global warming affects perennial plants. Gibberellin (GA) is recognized as a critical signal for dormancy release in woody perennials. This study explores the influence of GA and its signaling components on the dormancy release in sweet cherry. The external application of GA_4 + 7 significantly promoted the bud break rate and dormancy release. Notably, there was a substantial accumulation of GA₃, GA₄, and GA₇ in the buds, accompanied by a reduced concentration of abscisic acid (ABA) following GA treatment. RNA-Seq identified 8,610 differentially expressed transcripts in GA-treated buds compared to the Mock group. Transcriptome sequencing revealed differential expressions of PavGID1s, the GA receptor GID1, in sweet cherry flower buds after GA treatment. These findings were further verified across different seasons in sweet cherry. In both PavGID1b and PavGID1c, the open reading frame (ORF) is 1,032 bases long and encodes 344 amino acids. Overexpression of PavGID1b and PavGID1c resulted in early flowering and higher plants in Arabidopsis. However, these genes have opposing roles in seed germination in Arabidopsis. Furthermore, PavWRKY31 may regulate the stabilization and release of dormancy by modulating the transcriptional level of PavGID1c. PavGA20ox-2 and PavGID2 may also influence sweet cherry dormancy release by interacting with GID1s and affecting DELLA protein stability. These results provide a theoretical basis for understanding the regulatory effect of gibberellin on the bud dormancy of plants.

Timely seed germination is a crucial process for plant survival and subsequent propagation, which is significantly impacted by high temperatures. ROOT INITIATION DEFECTIVE 1 (RID1), an Arabidopsis DEAH/RHA RNA helicase, has been previously reported to modulate the cellular specification of mature female gametophyte and callus initiation from hypocotyl explants through proper alternative splicing. However, the role of RID1 in the regulation of seed germination remains largely unexplored. Here, we identified that mutations in RID1 delayed seed germination more severely at 28℃ compared to 22℃. Notably, we found that the rid1-1 mutation did not significantly alter genome-wide alternative splicing patterns during seed germination compared to the wild type. Further evidences demonstrated that RID1 regulates seed germination via the abscisic acid (ABA) pathway by physically and genetically interacting with the SKIP-associated transcriptional complex. These results suggest that RID1 regulates seed germination in response to ambient temperature at the transcriptional level rather than through alternative splicing regulation. This study provides novel insights into the mechanisms underlying the regulation of seed germination.