Impaired KIN10 function restores developmental defects in the Arabidopsis trehalose 6-phosphate synthase1 (tps1) mutant

Possible Mechanism of Sucrose and Trehalose-6-Phosphate in Regulating the Secondary Flower on the Strong Upright Spring Shoots of Blueberry Planted in Greenhouse

Secondary flowering is the phenomenon in which a tree blooms twice or more times a year. Along with the development of blueberry (Vaccinium corymbosum L.) fruits in spring, a large number of secondary flowers on the strong upright spring shoots were noticed in blueberries planted in the greenhouse. To reveal the cause and possible regulatory mechanism of the phenomenon, we clarified the phenological characteristics of flower bud differentiation and development on the spring shoots by combining phenological phenotype with anatomical observation. Furthermore, the changes in carbohydrates, trehalose-6-phosphate (Tre6P), and the relationship among the key enzyme regulatory genes for Tre6P metabolism and the key regulatory genes for flower formation during the differentiation process of apical buds and axillary buds were investigated. The results showed that the process of flower bud differentiation and flowering of apical and axillary buds was consistent, accompanied by a large amount of carbohydrate consumption. This process was positively correlated with the expression trends of VcTPS1/2, VcSnRK1, VcFT, VcLFY2, VcSPL43, VcAP1, and VcDAM in general, and negatively correlated with that of VcTPP. In addition, there is a certain difference in the differentiation progress of flower buds between the apical and axillary buds. Compared with axillary buds, apical buds had higher contents of sucrose, fructose, glucose, Tre6P, and higher expression levels of VcTPS2, VcFT, VcSPL43, and VcAP1. Moreover, VcTPS1 and VcTPS2 were more closely related to the physiological substances (sucrose and Tre6P) in axillary bud and apical bud differentiation, respectively. It was suggested that sucrose and trehalose-6-phosphate play a crucial role in promoting flower bud differentiation in strong upright spring shoots, and VcTPS1 and VcTPS2 might play a central role in these activities. Our study provided substantial sight for further study on the mechanism of multiple flowering of blueberries and laid a foundation for the regulation and utilization of the phenomenon of multiple flowering in a growing season of perennial woody plants.

SnRK1/TOR/T6P: three musketeers guarding energy for root growth

Sugars derived from photosynthesis, specifically sucrose, are the primary source of plant energy. Sucrose is produced in leaves and transported to the roots through the phloem, serving as a vital energy source. Environmental conditions can result in higher or lower photosynthesis, promoting anabolism or catabolism, respectively, thereby influencing the sucrose budget available for roots. Plants can adjust their root system to optimize the search for soil resources and to ensure the plant's adaptability to diverse environmental conditions. Recently, emerging research indicates that SNF1-RELATED PROTEIN KINASE 1 (SnRK1), trehalose 6-phosphate (T6P), and TARGET OF RAPAMYCIN (TOR) collectively serve as fundamental regulators of root development, together forming a signaling module to interpret the nutritional status of the plant and translate this to growth adjustments in the below ground parts.

Sucrose homeostasis: Mechanisms and opportunity in crop yield improvement

Sugar homeostasis is a critical feature of biological systems. In humans, raised and dysregulated blood sugar is a serious health issue. In plants, directed changes in sucrose homeostasis and allocation represent opportunities in crop improvement. Plant tissue sucrose varies more than blood glucose and is found at higher concentrations (cytosol and phloem ca. 100 mM v 3.9-6.9 mM for blood glucose). Tissue sucrose varies with developmental stage and environment, but cytosol and phloem exhibit tight sucrose control. Sucrose homeostasis is a consequence of the integration of photosynthesis, synthesis of storage end-products such as starch, transport of sucrose to sinks and sink metabolism. Trehalose 6-phosphate (T6P)-SnRK1 and TOR play central, still emerging roles in regulating and coordinating these processes. Overall, tissue sucrose levels are more strongly related to growth than to photosynthesis. As a key sucrose signal, T6P regulates sucrose levels, transport and metabolic pathways to coordinate source and sink at a whole plant level. Emerging evidence shows that T6P interacts with meristems. With careful targeting, T6P manipulation through exploiting natural variation, chemical intervention and genetic modification is delivering benefits for crop yields. Regulation of cereal grain set, filling and retention may be the most strategically important aspect of sucrose allocation and homeostasis for food security.

A sucrose non-fermenting-1-related protein kinase 1 gene from wheat, TaSnRK1α regulates starch biosynthesis by modulating AGPase activity

Major portion of wheat grain consist of carbohydrate, mainly starch. The proportion of amylose and amylopectin in starch greatly influence the end product quality. Advancement in understanding starch biosynthesis pathway and modulating key genes has enabled the genetic modification of crops resulting in enhanced starch quality. However, the regulation of starch biosynthesis genes still remains unexplored. So, to expand the limited knowledge, here, we characterized a Ser/Thr kinase, SnRK1α in wheat and determined its role in regulating starch biosynthesis. SnRK1 is an evolutionary conserved protein kinase and share homology to yeast SNF1. Yeast complementation assay suggests TaSnRK1α restores growth defect and promotes glycogen accumulation. Domain analysis and complementation assay with truncated domain proteins suggest the importance of ATP-binding and UBA domain in TaSnRK1α activity. Sub-cellular localization identified nuclear and cytoplasmic localization of TaSnRK1α in tobacco leaves. Further, heterologous over-expression (O/E) of TaSnRK1α in Arabidopsis not only led to increase in starch content but also enlarges the starch granules. TaSnRK1α was found to restore starch accumulation in Arabidopsis kin10. Remarkably, TaSnRK1α O/E increases the AGPase activity suggesting the direct regulation of rate limiting enzyme AGPase involved in starch biosynthesis. Furthermore, in vitro and in vivo interaction assay reveal that TaSnRK1α interacts with AGPase large sub-unit. Overall, our findings indicate that TaSnRK1α plays a role in starch biosynthesis by regulating AGPase activity.

Temporal regulation of vegetative phase change in plants

During their vegetative growth, plants reiteratively produce leaves, buds, and internodes at the apical end of the shoot. The identity of these organs changes as the shoot develops. Some traits change gradually, but others change in a coordinated fashion, allowing shoot development to be divided into discrete juvenile and adult phases. The transition between these phases is called vegetative phase change. Historically, vegetative phase change has been studied because it is thought to be associated with an increase in reproductive competence. However, this is not true for all species; indeed, heterochronic variation in the timing of vegetative phase change and flowering has made important contributions to plant evolution. In this review, we describe the molecular mechanism of vegetative phase change, how the timing of this process is controlled by endogenous and environmental factors, and its ecological and evolutionary significance.

Oligosaccharide production and signaling correlate with delayed flowering in an Arabidopsis genotype grown and selected in high [CO2]

Since industrialization began, atmospheric CO2 ([CO2]) has increased from 270 to 415 ppm and is projected to reach 800-1000 ppm this century. Some Arabidopsis thaliana (Arabidopsis) genotypes delayed flowering in elevated [CO2] relative to current [CO2], while others showed no change or accelerations. To predict genotype-specific flowering behaviors, we must understand the mechanisms driving flowering response to rising [CO2]. [CO2] changes alter photosynthesis and carbohydrates in plants. Plants sense carbohydrate levels, and exogenous carbohydrate application influences flowering time and flowering transcript levels. We asked how organismal changes in carbohydrates and transcription correlate with changes in flowering time under elevated [CO2]. We used a genotype (SG) of Arabidopsis that was selected for high fitness at elevated [CO2] (700 ppm). SG delays flowering under elevated [CO2] (700 ppm) relative to current [CO2] (400 ppm). We compared SG to a closely related control genotype (CG) that shows no [CO2]-induced flowering change. We compared metabolomic and transcriptomic profiles in these genotypes at current and elevated [CO2] to assess correlations with flowering in these conditions. While both genotypes altered carbohydrates in response to elevated [CO2], SG had higher levels of sucrose than CG and showed a stronger increase in glucose and fructose in elevated [CO2]. Both genotypes demonstrated transcriptional changes, with CG increasing genes related to fructose 1,6-bisphosphate breakdown, amino acid synthesis, and secondary metabolites; and SG decreasing genes related to starch and sugar metabolism, but increasing genes involved in oligosaccharide production and sugar modifications. Genes associated with flowering regulation within the photoperiod, vernalization, and meristem identity pathways were altered in these genotypes. Elevated [CO2] may alter carbohydrates to influence transcription in both genotypes and delayed flowering in SG. Changes in the oligosaccharide pool may contribute to delayed flowering in SG. This work extends the literature exploring genotypic-specific flowering responses to elevated [CO2].

Genome-Wide Identification of Trehalose-6-phosphate Synthase (TPS) Gene Family Reveals the Potential Role in Carbohydrate Metabolism in Peach

Trehalose-6-phosphate synthase (TPS) is essential for plant growth and development, linking trehalose-6-phosphate (T6P) to carbon metabolism. However, little is known about the TPS gene family in peaches and their potential roles in regulating carbohydrates in peach fruit. In this study, nine TPS genes were identified in the peach genome and named according to the homologous genes in Arabidopsis. Phylogenetic analysis showed that three subfamilies were identified, including TPSI, TPSII-1, and TPSII-2, which were also consistent with gene structure analysis. Considerable cis-elements were enriched in the promoters, including plant hormone-related elements. Tissue-specific analysis showed that these TPS genes were mainly expressed in leaves, stems, and fruit, showing different expression patterns for each gene. In addition, during fruit development, the content of trehalose-6-phosphate (T6P) was positively correlated with the expression of PpTPS7a and negatively with sucrose non-fermenting-1-related kinase 1 (SnRK1) activity. Transient overexpression and silencing of PpTPS7a in peach fruit validated its function in regulating T6P content and SnRK1 activity.

Functions of sucrose and trehalose 6-phosphate in controlling plant development

Plants exhibit enormous plasticity in regulating their architecture to be able to adapt to a constantly changing environment and carry out vital functions such as photosynthesis, anchoring, and nutrient uptake. Phytohormones play a role in regulating these responses, but sugar signalling mechanisms are also crucial. Sucrose is not only an important source of carbon and energy fuelling plant growth, but it also functions as a signalling molecule that influences various developmental processes. Trehalose 6-phosphate (Tre6P), a sucrose-specific signalling metabolite, is emerging as an important regulator in plant metabolism and development. Key players involved in sucrose and Tre6P signalling pathways, including MAX2, SnRK1, bZIP11, and TOR, have been implicated in processes such as flowering, branching, and root growth. We will summarize our current knowledge of how these pathways shape shoot and root architecture and highlight how sucrose and Tre6P signalling are integrated with known signalling networks in shaping plant growth.

An overview of floral regulatory genes in annual and perennial plants

The floral initiation in angiosperms is a complex process influenced by endogenous and exogenous signals. With this approach, we aim to provide a comprehensive review to integrate this complex floral regulatory process and summarize the regulatory genes and their functions in annuals and perennials. Seven primary paths leading to flowering have been discovered in Arabidopsis under several growth condition that include; photoperiod, ambient temperature, vernalization, gibberellins, autonomous, aging and carbohydrates. These pathways involve a series of interlinked signaling pathways that respond to both internal and external signals, such as light, temperature, hormones, and developmental cues, to coordinate the expression of genes that are involved in flower development. Among them, the photoperiodic pathway was the most important and conserved as some of the fundamental loci and mechanisms are shared even by closely related plant species. The activation of floral regulatory genes such as FLC, FT, LFY, and SOC1 that determine floral meristem identity and the transition to the flowering stage result from the merging of these pathways. Recent studies confirmed that alternative splicing, antisense RNA and epigenetic modification play crucial roles by regulating the expression of genes related to blooming. In this review, we documented recent progress in the floral transition time in annuals and perennials, with emphasis on the specific regulatory mechanisms along with the application of various molecular approaches including overexpression studies, RNA interference and Virus-induced flowering. Furthermore, the similarities and differences between annual and perennial flowering will aid significant contributions to the field by elucidating the mechanisms of perennial plant development and floral initiation regulation.

The trehalose 6-phosphate phosphatase family in plants

Trehalose 6-phosphate (Tre6P), the intermediate of trehalose biosynthesis, is an essential signalling metabolite linking plant growth and development to carbon metabolism. While recent work has focused predominantly on the enzymes that produce Tre6P, little is known about the proteins that catalyse its degradation, the trehalose 6-phosphate phosphatases (TPPs). Often occurring in large protein families, TPPs exhibit cell-, tissue- and developmental stage-specific expression patterns, suggesting important regulatory functions in controlling local levels of Tre6P and trehalose as well as Tre6P signalling. Furthermore, growing evidence through gene expression studies and transgenic approaches shows that TPPs play an important role in integrating environmental signals with plant metabolism. This review highlights the large diversity of TPP isoforms in model and crop plants and identifies how modulating Tre6P metabolism in certain cell types, tissues, and at different developmental stages may promote stress tolerance, resilience and increased crop yield.

HEXOKINASE1 and glucose-6-phosphate fuel plant growth and development

As photoautotrophic organisms, plants produce an incredible spectrum of pigments, anti-herbivory compounds, structural materials and energic intermediates. These biosynthetic routes help plants grow, reproduce and mitigate stress. HEXOKINASE1 (HXK1), a metabolic enzyme and glucose sensor, catalyzes the phosphorylation of hexoses, a key introductory step for many of these pathways. However, previous studies have largely focused on the glucose sensing and signaling functions of HXK1, and the importance of the enzyme's catalytic function is only recently being connected to plant development. In this brief Spotlight, we describe the developmental significance of plant HXK1 and its role in plant metabolic pathways, specifically in glucose-6-phosphate production. Furthermore, we describe the emerging connections between metabolism and development and suggest that HXK1 signaling and catalytic activity regulate discrete areas of plant development.

Sailing in complex nutrient signaling networks: Where I am, where to go, and how to go?

To ensure survival and promote growth, sessile plants have developed intricate internal signaling networks tailored in diverse cells and organs with both shared and specialized functions that respond to various internal and external cues. A fascinating question arises: how can a plant cell or organ diagnose the spatial and temporal information it is experiencing to know "where I am," and then is able to make the accurate specific responses to decide "where to go" and "how to go," despite the absence of neuronal systems found in mammals. Drawing inspiration from recent comprehensive investigations into diverse nutrient signaling pathways in plants, this review focuses on the interactive nutrient signaling networks mediated by various nutrient sensors and transducers. We assess and illustrate examples of how cells and organs exhibit specific responses to changing spatial and temporal information within these interactive plant nutrient networks. In addition, we elucidate the underlying mechanisms by which plants employ posttranslational modification codes to integrate different upstream nutrient signals, thereby conferring response specificities to the signaling hub proteins. Furthermore, we discuss recent breakthrough studies that demonstrate the potential of modulating nutrient sensing and signaling as promising strategies to enhance crop yield, even with reduced fertilizer application.

Artificial warming affects sugar signals and flavonoid accumulation to improve female willows' growth faster than males

Increasing global warming is severely affecting tree growth and development. However, research on the sex-specific responses of dioecious trees to warming is scarce. Here, male and female Salix paraplesia were selected for artificial warming (an increase of 4 °C relative to ambient temperature) to investigate the effects on morphological, physiological, biochemical and molecular responses. The results showed that warming significantly promoted the growth of female and male S. paraplesia, but females grew faster than males. Warming affected photosynthesis, chloroplast structures, peroxidase activity, proline, flavonoids, nonstructural carbohydrates (NSCs) and phenolic contents in both sexes. Interestingly, warming increased flavonoid accumulation in female roots and male leaves but inhibited it in female leaves and male roots. The transcriptome and proteome results indicated that differentially expressed genes and proteins were significantly enriched in sucrose and starch metabolism and flavonoid biosynthesis pathways. The integrative analysis of transcriptomic, proteomic, biochemical and physiological data revealed that warming changed the expression of SpAMY, SpBGL, SpEGLC and SpAGPase genes, resulting in the reduction of NSCs and starch and the activation of sugar signaling, particularly SpSnRK1s, in female roots and male leaves. These sugar signals subsequently altered the expression of SpHCTs, SpLAR and SpDFR in the flavonoid biosynthetic pathway, ultimately leading to the differential accumulation of flavonoids in female and male S. paraplesia. Therefore, warming causes sexually differential responses of S. paraplesia, with females performing better than males.

SnRK1 inhibits anthocyanin biosynthesis through both transcriptional regulation and direct phosphorylation and dissociation of the MYB/bHLH/TTG1 MBW complex

Plants have evolved an extensive specialized secondary metabolism. The colorful flavonoid anthocyanins, for example, not only stimulate flower pollination and seed dispersal, but also protect different tissues against high light, UV and oxidative stress. Their biosynthesis is highly regulated by environmental and developmental cues and induced by high sucrose levels. Expression of the biosynthetic enzymes involved is controlled by a transcriptional MBW complex, comprising (R2R3) MYB- and bHLH-type transcription factors and the WD40 repeat protein TTG1. Anthocyanin biosynthesis is not only useful, but also carbon- and energy-intensive and non-vital. Consistently, the SnRK1 protein kinase, a metabolic sensor activated in carbon- and energy-depleting stress conditions, represses anthocyanin biosynthesis. Here we show that Arabidopsis SnRK1 represses MBW complex activity both at the transcriptional and post-translational level. In addition to repressing expression of the key transcription factor MYB75/PAP1, SnRK1 activity triggers MBW complex dissociation, associated with loss of target promoter binding, MYB75 protein degradation and nuclear export of TTG1. We also provide evidence for direct interaction with and phosphorylation of multiple MBW complex proteins. These results indicate that repression of expensive anthocyanin biosynthesis is an important strategy to save energy and redirect carbon flow to more essential processes for survival in metabolic stress conditions.

The strigolactone pathway plays a crucial role in integrating metabolic and nutritional signals in plants

Strigolactones are rhizosphere signals and phytohormones that play crucial roles in plant development. They are also well known for their role in integrating nitrate and phosphate signals to regulate shoot and root development. More recently, sugars and citrate (an intermediate of the tricarboxylic acid cycle) were reported to inhibit the strigolactone response, with dramatic effects on shoot architecture. This Review summarizes the discoveries recently made concerning the mechanisms through which the strigolactone pathway integrates sugar, metabolite and nutrient signals. We highlight here that strigolactones and MAX2-dependent signalling play crucial roles in mediating the impacts of nutritional and metabolic cues on plant development and metabolism. We also discuss and speculate concerning the role of these interactions in plant evolution and adaptation to their environment.

In vivo protein kinase activity of SnRK1 fluctuates in Arabidopsis rosettes during light-dark cycles

Sucrose-nonfermenting 1 (SNF1)-related kinase 1 (SnRK1) is a central hub in carbon and energy signaling in plants, and is orthologous with SNF1 in yeast and the AMP-activated protein kinase (AMPK) in animals. Previous studies of SnRK1 relied on in vitro activity assays or monitoring of putative marker gene expression. Neither approach gives unambiguous information about in vivo SnRK1 activity. We have monitored in vivo SnRK1 activity using Arabidopsis (Arabidopsis thaliana) reporter lines that express a chimeric polypeptide with an SNF1/SnRK1/AMPK-specific phosphorylation site. We investigated responses during an equinoctial diel cycle and after perturbing this cycle. As expected, in vivo SnRK1 activity rose toward the end of the night and rose even further when the night was extended. Unexpectedly, although sugars rose after dawn, SnRK1 activity did not decline until about 12 h into the light period. The sucrose signal metabolite, trehalose 6-phosphate (Tre6P), has been shown to inhibit SnRK1 in vitro. We introduced the SnRK1 reporter into lines that harbored an inducible trehalose-6-phosphate synthase construct. Elevated Tre6P decreased in vivo SnRK1 activity in the light period, but not at the end of the night. Reporter polypeptide phosphorylation was sometimes negatively correlated with Tre6P, but a stronger and more widespread negative correlation was observed with glucose-6-phosphate. We propose that SnRK1 operates within a network that controls carbon utilization and maintains diel sugar homeostasis, that SnRK1 activity is regulated in a context-dependent manner by Tre6P, probably interacting with further inputs including hexose phosphates and the circadian clock, and that SnRK1 signaling is modulated by factors that act downstream of SnRK1.

Genome-Wide Investigation of the NAC Transcription Factor Family in Apocynum venetum Revealed Their Synergistic Roles in Abiotic Stress Response and Trehalose Metabolism

NAC (NAM, ATAF1/2, and CUC2) transcription factors (TFs) are one of the most prominent plant-specific TF families and play essential roles in plant growth, development and adaptation to abiotic stress. Although the NAC gene family has been extensively characterized in many species, systematic analysis is still relatively lacking in Apocynum venetum (A. venetum). In this study, 74 AvNAC proteins were identified from the A. venetum genome and were classified into 16 subgroups. This classification was consistently supported by their gene structures, conserved motifs and subcellular localizations. Nucleotide substitution analysis (Ka/Ks) showed the AvNACs to be under the influence of strong purifying selection, and segmental duplication events were found to play the dominant roles in the AvNAC TF family expansion. Cis-elements analysis demonstrated that the light-, stress-, and phytohormone-responsive elements being dominant in the AvNAC promoters, and potential TFs including Dof, BBR-BPC, ERF and MIKC_MADS were visualized in the TF regulatory network. Among these AvNACs, AvNAC58 and AvNAC69 exhibited significant differential expression in response to drought and salt stresses. The protein interaction prediction further confirmed their potential roles in the trehalose metabolism pathway with respect to drought and salt resistance. This study provides a reference for further understanding the functional characteristics of NAC genes in the stress-response mechanism and development of A. venetum.

Mapping of the plant SnRK1 kinase signalling network reveals a key regulatory role for the class II T6P synthase-like proteins

The central metabolic regulator SnRK1 controls plant growth and survival upon activation by energy depletion, but detailed molecular insight into its regulation and downstream targets is limited. Here we used phosphoproteomics to infer the sucrose-dependent processes targeted upon starvation by kinases as SnRK1, corroborating the relation of SnRK1 with metabolic enzymes and transcriptional regulators, while also pointing to SnRK1 control of intracellular trafficking. Next, we integrated affinity purification, proximity labelling and crosslinking mass spectrometry to map the protein interaction landscape, composition and structure of the SnRK1 heterotrimer, providing insight in its plant-specific regulation. At the intersection of this multi-dimensional interactome, we discovered a strong association of SnRK1 with class II T6P synthase (TPS)-like proteins. Biochemical and cellular assays show that TPS-like proteins function as negative regulators of SnRK1. Next to stable interactions with the TPS-like proteins, similar intricate connections were found with known regulators, suggesting that plants utilize an extended kinase complex to fine-tune SnRK1 activity for optimal responses to metabolic stress.

Comparative Analysis on the Evolution of Flowering Genes in Sugar Pathway in Brassicaceae

Sugar plays an important role in regulating the flowering of plants. However, studies of genes related to flowering regulation by the sugar pathway of Brassicaceae plants are scarce. In this study, we performed a comprehensive comparative genomics analysis of the flowering genes in the sugar pathway from seven members of the Brassicaceae, including: Arabidopsis thaliana, Arabidopsis lyrata, Astelia pumila, Camelina sativa, Brassica napus, Brassica oleracea, and Brassica rapa. We identified 105 flowering genes in the sugar pathway of these plants, and they were categorized into nine groups. Protein domain analysis demonstrated that the IDD8 showed striking structural variations in different Brassicaceae species. Selection pressure analysis revealed that sugar pathway genes related to flowering were subjected to strong purifying selection. Collinearity analysis showed that the identified flowering genes expanded to varying degrees, but SUS4 was absent from the genomes of Astelia pumila, Camelina sativa, Brassica napus, Brassica oleracea, and Brassica rapa. Tissue-specific expression of ApADG indicated functional differentiation. To sum up, genome-wide identification revealed the expansion, contraction, and diversity of flowering genes in the sugar pathway during Brassicaceae evolution. This study lays a foundation for further study on the evolutionary characteristics and potential biological functions of flowering genes in the sugar pathway of Brassicaceae.

Integrated Transcriptome and Targeted Metabolite Analysis Reveal miRNA-mRNA Networks in Low-Light-Induced Lotus Flower Bud Abortion

Most Nelumbo nucifera (lotus) flower buds were aborted during the growing season, notably in low-light environments. How lotus produces so many aborted flower buds is largely unknown. An integrated transcriptome and targeted metabolite analysis was performed to reveal the genetic regulatory networks underlying lotus flower bud abortion. A total of 233 miRNAs and 25,351 genes were identified in lotus flower buds, including 68 novel miRNAs and 1108 novel genes. Further enrichment analysis indicated that sugar signaling plays a potential central role in regulating lotus flower bud abortion. Targeted metabolite analysis showed that trehalose levels declined the most in the aborting flower buds. A potential regulatory network centered on miR156 governs lotus flower bud abortion, involving multiple miRNA-mRNA pairs related to cell integrity, cell proliferation and expansion, and DNA repair. Genetic analysis showed that miRNA156-5p-overexpressing lotus showed aggravated flower bud abortion phenotypes. Trehalose-6-P synthase 1 (TPS1), which is required for trehalose synthase, had a negative regulatory effect on miR156 expression. TPS1-overexpression lotus showed significantly decreased flower bud abortion rates both in normal-light and low-light environments. Our study establishes a possible genetic basis for how lotus produces so many aborted flower buds, facilitating genetic improvement of lotus' shade tolerance.