Plant Growth Regulation最新文献

The MAPK cascade, evolutionarily conserved among eukaryotes, plays a crucial role in regulating plant growth, development, and resistance to both biotic and abiotic stresses. However, the gene function of MAPK cascade in foxtail millet (Setaria italica) is poorly studied. In this study, RNA sequencing revealed that the MAPK cascade is the primary enrichment pathway in foxtail millet under salt treatment. Meanwhile, fourteen genes encoding mitogen-activated protein kinase kinases (SiMKKs) were identified and could be categorized into four subfamilies. Under salt treatment, the expression of 11 SiMKKs was upregulated, with SiMKK6-2 in group A showing the most significant increase. SiMKK1 and SiMKK6-1, the other two members of the same subfamily, were also significantly upregulated under salt stress. Overexpression of these three genes in Arabidopsis thaliana reduced the sensitivity of roots to salt stress. The transgenic plants exhibited an increase in lateral roots. Under salt stress, the decrease in primary root length of transgenic plants was significantly less than that of wild-type plants. These three genes are involved in regulating the development of primary and lateral roots of plants, which can maintain better root development to improve plant tolerance to salt stress.

Populus davidiana × P. bolleana is an economically important tree species for the development of timber plantations, especially in Northern China. Populus davidiana × P. bolleana plays a role in forest production and environment. Nowadays, the effect of atmospheric carbon dioxide (CO₂)-caused climate change is an increasing concern and will affect plant secondary metabolism. In this study, transcriptomic and untargeted metabolome responses of Populus davidiana × P. bolleana to elevated concentrations of CO₂ were studied. Populus davidiana × P. bolleana were grown under three concentration of CO₂ (397 ppm, 550 ppm, 750 ppm) for 30 days. A total of 127,088,734 clean reads were obtained and assembled into 50498 unigenes (118087 transcripts); 50498 unigenes were annotated using different databases (NR, Swiss-Prot, KEGG, GO, eggNOG and Pfam). Additionally, 6416 differentially expressed genes (DEGs) were identified including 3202 up- and 3214 down-regulated genes. “Phenylpropanoid biosynthesis” and “flavonoid biosynthesis” enrich into the Kyoto encyclopedia of genes and genomes (KEGG) pathway. Moreover, 10460 and 9852 metabolites ions were identified using positive (pos) mode and negative (neg) mode, respectively. We conducted correlation analyses of enriched KEGG pathways of DEGs and accumulated metabolites, revealing that phenylpropanoid and flavonoid secondary metabolism pathways were enriched under CO₂ stress. The findings provide new insights of a molecular mechanism responsible for adaption of Populus davidiana × P. bolleana to CO₂ stress.

Graphical abstract

Investigated the effects of elevated CO₂ on Populus davidiana × P. bolleana using transcriptome and metabolome analysis. Results revealed changes in differentially expressed genes (DEGs) associated with phenylpropanoid and flavonoid biosynthesis pathways, suggesting an impact on the production of these metabolites.

The effects of blue-light irradiation on abscisic acid (ABA) signaling, sugar metabolism and translocation, and photoreceptors and gene expressions were investigated to clarify the mechanism by which blue-LED irradiation increases sugar concentrations in grape berries (Vitis labruscana L.). Blue light-emitting diode (LED) irradiation increased the portion of ¹³C-photosynthates in the grapevine clusters that were fed ¹³CO₂; compared to the portion in the cluster in the untreated control. Fructose and glucose concentrations and the expressions of VvSWEET10, VvSUC11, and VvSUS4 in blue LED-irradiated berries were increased. The blue LED-irradiated berries’ sucrose concentrations were significantly lower than the untreated control at 14 days after treatment. We speculated that the blue LED-treated berries’ decreased sucrose was associated with the increased Sugars Will Eventually be Exported Transporter (VvSWEET10), sucrose transporter (VvSUC11), and sucrose synthase (VvSUS4) expressions and promoted the translocation of ¹³C-photosynthates from the leaves that were fed ¹³CO₂. Blue-LED irradiation increased the expressions of SNF1-related protein kinases (VvSnRK2.6) and ABA responding element binding transcription factor (VvABF1), while decreasing the expression of protein phosphateses 2C9 (VvPP2C9) genes, which are related to ABA signaling. Blue-LED irradiation increased the expressions of cryptochrome (VvCRYa) and phototropin (VvPHOT2), which are photoreceptor genes. The application of the pyrabactin resistance-like (PYL)-PP2C ABA receptor interaction antagonist AS6 did not affect endogenous ABA concentrations in the grape berries, but it decreased sucrose concentrations at harvest. The application of ABA did not affect sucrose, glucose, or fructose concentrations or the expressions of VvSnRK2.6 and VvPP2C9. The application of nordihydroguaiaretic acid (NDGA, an inhibitor of 9-cis-epoxycarotenoid dioxygenase activity in ABA biosynthesis) did not affect sugar concentrations at harvest. These results suggest that upregulation of photoreceptor gene expressions and ABA signaling are associated with sugar concentrations in grape berries.

Dormancy is a mechanism for perennial trees to resist unfavourable environmental conditions. However, the molecular mechanisms underlying dormancy in apricots have not been fully characterized. Here, we investigated the content of the abscisic acid (ABA) in floral buds, which exhibited a decreasing trend from paradormancy to ecodormancy stages (D1–D3). Combining mRNA and miRNA analyses, 1458 miRNAs corresponding to 28,501 target genes were identified at three stages. The results of DEGs and DE miRNAs showed that 38 DEGs and 10 DE miRNAs responded to low temperatures and short photoperiods were found involved in maintaining the dormancy, and four genes (PaNCED2, PaCYP707A4.1, PaPYL, and PaABF1) and miR5776-x involved in ABA biosynthesis and signaling pathways. Based on weighted gene co-expression network analysis (WGCNA), PaABF1 was identified as the key factor maintaining the dormancy. The findings provide new molecular mechanisms for further research of regulation of dormancy in apricot.

Gibberellin acid (GA₃) and forchlorfenuron (CPPU) are used for the development and expansion of fruits. However, the fruit size, endogenous hormone content and molecular mechanism of mango (Mangifera indica L.) fruit development in response to GA₃ and CPPU treatment are not clear. In this study, mango trees were sprayed with GA₃ and CPPU at four different doses, and a variety of physiological and biochemical indexs were examined. The transcriptomes of mango fruits at different developmental stages were thoroughly examined via transcriptome high-throughput sequencing technology. The results showed that mango fruit increased significantly after GA₃ and CPPU treatment. The contents of GA₃, cytokinin (CTK), indoleacetic acid (IAA) and jasmonic acid (JA) increased in mango pulp under GA₃ and CPPU treatment; however, abscisic acid (ABA) accumulation decreased. These trends align with those of the GA₃ and CPPU treatments, which promoted mango growth and fruit development. The values of 20.00 ∼ 33.33 mg/L GA₃ and 15 mg/L CPPU are the most appropriate. Transcriptome analysis revealed that many differentially expressed genes (DEGs) involved in plant hormone signal transduction are linked to the development and expansion of mango fruits. Additional investigations revealed a number of genes linked to auxin, gibberellin, and fruit expansion, including eleven expansin (EXP) genes, six xyloglucan endotransglycosylase/hydrolase (XTH) genes, six auxin/indole-3-acetic acid (Aux/IAA) genes, two auxin response factor (ARF) genes, one gibberellin 2-oxidase (GA2ox) gene and one gibberellin 3-oxidase (GA3ox) gene. These results shed light on the key genes involved in mango fruit development in response to GA₃ and CPPU treatments and advance our understanding of the molecular mechanisms underlying these treatments.

The nutritional value of broccoli is largely attributed to its abundant secondary metabolites such as phenolic compounds and glucosinolates (GSLs). However, the dynamic relationship between these compounds, including potential synergistic or antagonistic interactions that influence plant physiology and metabolism, remains unclear. In this study, we aimed to elucidate the intricate interplay between phenolic compounds and GSLs in broccoli plants and their consequent effects on primary metabolism and regulatory mechanisms governing water and nutrient uptake. To investigate this, we externally supplied citric phenolic compounds to broccoli plants, and then measured the levels of GSLs and phenolic compounds, along with assessing physiological parameters such as biomass, gas exchange, and nutrient content. Additionally, the expression of genes related to GSLs and phenolics biosynthesis, as well as genes involved in water transport were measured. Our results revealed a complex interrelation between phenolic compounds and GSLs, with phenolic compounds significantly modulating the response of GSLs and influencing the expression of aquaporin genes. This modulation had notable effects on nutrient regulation mechanisms in broccoli plants. Overall, our findings shed light on the regulatory mechanisms underlying the interaction between phenolic compounds, GSLs and growth, providing insights into their roles in plant physiology and metabolism.

Heterophyllin B (HB) is a small molecule cyclic peptide (CP) compound with important pharmacological activities. This CP is specifically produced in Chinese herb Pseudostellaria heterophylla. However, the production of HB in P. heterophylla is often limited, and fails to meet market demands. Phytohormones play regulatory roles in medicinal plant secondary metabolism. We treated P. heterophylla tuberous roots with various concentrations of methyl jasmonate (MeJA) and observed a higher HB content at 200 μM MeJA treatment. Subsequently, we collected the tuberous roots exposed to 200 μM MeJA for 0, 6, and 12 h (MeJA-0 h, MeJA-6 h, and MeJA-12 h) and subjected them to transcriptome sequencing. A total of 82,363 unigenes were identified and categorized according to publicly available data. KEGG analysis indicated that the differentially expressed genes (DEGs) were significantly associated with metabolic pathways such as plant hormone signaling pathways, phenylpropanoid biosynthesis, and the MAPK signal transduction-plant. Notably, MeJA also significantly promoted the expression of the precursor gene (prePhHB) of HB biosynthesis. Six transcription factors (TFs) were chosen as candidate genes for regulating HB biosynthesis. qRT-PCR further demonstrated that PhNAC1 and PhMYB2 exhibited a similar expression pattern to prePhHB. In summary, the transcriptome of P. heterophylla seedlings treated with MeJA was analyzed, and potential regulatory genes related to HB biosynthesis of P. heterophylla were obtained, establishing a foundation for further investigation into the biosynthesis and regulation of CPs.

Phosphate (P) is a crucial nutrient serving ATP biosynthesis and activating enzymes in important signal transduction pathways. Zinc (Zn) is another important micronutrient that plays a structural role in enzymes and regulatory proteins. P and Zn might work synergistically in plant processes like root development, photosynthesis, and respiration. But P often interacts with other micronutrients such as Manganese (Mn), Iron (Fe), Copper (Cu), and Zinc (Zn), which can influence their absorption and accumulation. Among those interactions, P-Zn interaction is the most discussed as a high amount of P impedes Zn bioavailability and vice-versa. Though the influence of this interaction in plants is reflected only at morphological and physiological levels, it is imperative to consider their cross-talk at three different levels i.e., in soil, during plant uptake, and at the time of translocation to the aerial parts. In common agricultural practices, crop plants are force-fed with P fertilizers to maximize yield which hinders Zn availability. Incessant, indiscriminate, and repetitive application of P and Zn-based fertilizers also affects soil health. This review brings forth and discusses various levels of P-Zn interaction in plants and soil, highlighting the missing links that require further study or validation. The review also summarizes the different approaches that can be taken to mitigate P-Zn negative interaction to achieve better and sustainable crop productivity in the future.

The green peach aphid (GPA) is considered one of the most destructive pests posing a significant threat to the growth and fruit quality of peach trees (Prunus persica). Long non-coding RNAs (lncRNAs) represent an essential group of endogenous RNAs that play gene regulatory roles in plants. In this study, we identified 1776 lncRNAs from healthy and GPA-infested P. persica tissues, employing high-throughput strand-specific RNA sequencing. Our rigorous analysis of differential gene expression yielded 2871 differentially-expressed genes (DEGs), with 1803 genes exhibiting upregulation and 1068 genes exhibiting downregulation in response to the presence of GPA in peach trees. Our findings reveal the potential of lncRNAs to serve as crucial microRNA (miRNA) targets, thereby exerting a significant influence on miRNA activity. We further predicted two differentially expressed lncRNA–DEG pairs (circ16–miR482a and circ116–miR319a) associated with jasmonic acid (JA) pathway. Notably, endogenous JA levels in peach trees were continuously induced, primarily as a resistance mechanism against GPA infestation. Furthermore, spray application of JA significantly curtailed the GPA population.

Drought and heat during flowering critically reduce maize seed set. Current understanding of how these conditions affect pollen release and silk development, which are key determinants of seed set, remains inadequate, particularly under combined water deficit (WD) and high temperature (HT) stresses. This study evaluated the effects of drought and heat on seed set in two maize hybrids, Zhengdan 958 and Demeiya 1, derived from temperate and cool-temperate regions, respectively. These hybrids were exposed to conditions of water deficit, high temperature, and combined water deficit and high temperature (WDHT) within semi-automatic rainout shelters in field ponds, enabling precise simulation of environmental stresses. Relative to controls, seed set in Zhengdan 958 decreased by 32% under WD, 30% under HT, and 41% under combined WDHT conditions. In Demeiya 1, seed set reductions were 26% for WD, 25% for HT, and 34% for WDHT. These reductions were linked to notable decreases in silk fresh weight, pollen weight, and pollen activity. Additionally, the ¹³C content in anthers and the dry matter allocated to tassels decreased by 14.5–53.5% and 3.0–21.0%, respectively. Similarly, the ¹³C content in silks and dry matter allocated to ears decreased by 61.0–91.5% and 14.0–40.0%, respectively. Cross-pollination studies indicated that both hybrids exhibited similar sensitivities to WD and HT; however, silk was more vulnerable under WD and pollen more so under HT in Zhengdan 958, while the reverse was true for Demeiya 1. The combined stresses of WDHT had the most severe effects on both silk and pollen in both hybrids. The observed decreases in seed set under stress conditions were primarily due to limited carbohydrate and dry matter accumulation in reproductive tissues, which impacted silk weight, pollen release, and viability. These findings highlight the critical impact of environmental stresses on the reproductive success of maize, emphasizing the need for strategies to enhance resilience to combined abiotic stresses.