Comprehensive transcriptome and proteome analyses reveal a novel sodium chloride responsive gene network in maize seed tissues during germination

Unravelling the Significance of Seed Proteomics: Insights into Seed Development, Function, and Agricultural Applications

Seeds are essential for plant reproduction, ensuring species survival and dispersal while adapting to diverse environments throughout a plant's life. Proteomics has emerged as a powerful tool for deciphering the complexities of seed growth, germination, and stress responses. Advanced proteomic technologies enable the analysis of protein changes during germination, dormancy, and ageing, enhancing our understanding of seed lifespan and vitality. Recent studies have revealed detailed insights into metabolic processes and storage protein profiles across various plant species. This knowledge is crucial for improving seed storage, conserving quality, and maintaining viability. Additionally, it contributes to sustainable agriculture by identifying stress-responsive proteins and signalling pathways that can mitigate stress and enhance farming practices. This review highlights significant advancements in seed proteomics over the past decade, discussing critical discoveries related to storage proteins, protein interactions, and proteome modifications due to stress. It illustrates how these insights transform seed biology, boosting productivity, food security, and environmentally friendly practices. The review also identifies existing knowledge gaps and provides direction for future research, underscoring the need for continued interdisciplinary collaboration in this dynamic field.

Stabilization of dimeric PYR/PYL/RCAR family members relieves abscisic acid-induced inhibition of seed germination

Abscisic acid (ABA) is the primary preventing factor of seed germination, which is crucial to plant survival and propagation. ABA-induced seed germination inhibition is mainly mediated by the dimeric PYR/PYL/RCAR (PYLs) family members. However, little is known about the relevance between dimeric stability of PYLs and seed germination. Here, we reveal that stabilization of PYL dimer can relieve ABA-induced inhibition of seed germination using chemical genetic approaches. Di-nitrobensulfamide (DBSA), a computationally designed chemical probe, yields around ten-fold improvement in receptor affinity relative to ABA. DBSA reverses ABA-induced inhibition of seed germination mainly through dimeric receptors and recovers the expression of ABA-responsive genes. DBSA maintains PYR1 in dimeric state during protein oligomeric state experiment. X-ray crystallography shows that DBSA targets a pocket in PYL dimer interface and may stabilize PYL dimer by forming hydrogen networks. Our results illustrate the potential of PYL dimer stabilization in preventing ABA-induced seed germination inhibition.

Research Progress on the Mechanism of Salt Tolerance in Maize: A Classic Field That Needs New Efforts

Maize is the most important cereal crop globally. However, in recent years, maize production faced numerous challenges from environmental factors due to the changing climate. Salt stress is among the major environmental factors that negatively impact crop productivity worldwide. To cope with salt stress, plants developed various strategies, such as producing osmolytes, increasing antioxidant enzyme activity, maintaining reactive oxygen species homeostasis, and regulating ion transport. This review provides an overview of the intricate relationships between salt stress and several plant defense mechanisms, including osmolytes, antioxidant enzymes, reactive oxygen species, plant hormones, and ions (Na⁺, K⁺, Cl^-), which are critical for salt tolerance in maize. It addresses the regulatory strategies and key factors involved in salt tolerance, aiming to foster a comprehensive understanding of the salt tolerance regulatory networks in maize. These new insights will also pave the way for further investigations into the significance of these regulations in elucidating how maize coordinates its defense system to resist salt stress.

Comparative analysis of tissue-specific genes in maize based on machine learning models: CNN performs technically best, LightGBM performs biologically soundest

Introduction: With the advancement of RNA-seq technology and machine learning, training large-scale RNA-seq data from databases with machine learning models can generally identify genes with important regulatory roles that were previously missed by standard linear analytic methodologies. Finding tissue-specific genes could improve our comprehension of the relationship between tissues and genes. However, few machine learning models for transcriptome data have been deployed and compared to identify tissue-specific genes, particularly for plants. Methods: In this study, an expression matrix was processed with linear models (Limma), machine learning models (LightGBM), and deep learning models (CNN) with information gain and the SHAP strategy based on 1,548 maize multi-tissue RNA-seq data obtained from a public database to identify tissue-specific genes. In terms of validation, V-measure values were computed based on k-means clustering of the gene sets to evaluate their technical complementarity. Furthermore, GO analysis and literature retrieval were used to validate the functions and research status of these genes. Results: Based on clustering validation, the convolutional neural network outperformed others with higher V-measure values as 0.647, indicating that its gene set could cover as many specific properties of various tissues as possible, whereas LightGBM discovered key transcription factors. The combination of three gene sets produced 78 core tissue-specific genes that had previously been shown in the literature to be biologically significant. Discussion: Different tissue-specific gene sets were identified due to the distinct interpretation strategy for machine learning models and researchers may use multiple methodologies and strategies for tissue-specific gene sets based on their goals, types of data, and computational resources. This study provided comparative insight for large-scale data mining of transcriptome datasets, shedding light on resolving high dimensions and bias difficulties in bioinformatics data processing.

Alternative splicing in ABA signaling during seed germination

Seed germination is an essential step in a plant's life cycle. It is controlled by complex physiological, biochemical, and molecular mechanisms and external factors. Alternative splicing (AS) is a co-transcriptional mechanism that regulates gene expression and produces multiple mRNA variants from a single gene to modulate transcriptome diversity. However, little is known about the effect of AS on the function of generated protein isoforms. The latest reports indicate that alternative splicing (AS), the relevant mechanism controlling gene expression, plays a significant role in abscisic acid (ABA) signaling. In this review, we present the current state of the art about the identified AS regulators and the ABA-related changes in AS during seed germination. We show how they are connected with the ABA signaling and the seed germination process. We also discuss changes in the structure of the generated AS isoforms and their impact on the functionality of the generated proteins. Also, we point out that the advances in sequencing technology allow for a better explanation of the role of AS in gene regulation by more accurate detection of AS events and identification of full-length splicing isoforms.

Transcriptome and DNA Methylome Analysis of Two Contrasting Rice Genotypes under Salt Stress during Germination

With climate change and labor shortages, direct-seeding rice cultivation is becoming popular worldwide, especially in Asia. Salinity stress negatively affects rice seed germination in the direct-seeding process, and the cultivation of suitable direct-seeding rice varieties under salinity stress is necessary. However, little is known about the underlying mechanism of salt responses during seed germination under salt stress. To investigate the salt tolerance mechanism at the seed germination stage, two contrasting rice genotypes differing in salt tolerance, namely, FL478 (salt-tolerant) and IR29 (salt-sensitive), were used in this study. We observed, that compared to IR29, FL478 appeared to be more tolerant to salt stress with a higher germination rate. GD1 (germination defective 1), which was involved in seed germination by regulating alpha-amylase, was upregulated significantly in the salt-sensitive IR29 strain under salt stress during germination. Transcriptomic data showed that salt-responsive genes tended to be up/downregulated in IR29 but not in FL478. Furthermore, we investigated the epigenetic changes in FL478 and IR29 during germination under saline treatment using whole genome bisulfite DNA sequencing (BS-seq) technology. BS-seq data showed that the global CHH methylation level increased dramatically under salinity stress in both strains, and the hyper CHH differentially methylated regions (DMRs) were predominantly located within the transposable elements regions. Compared with FL478, differentially expressed genes with DMRs in IR29 were mainly related to gene ontology terms such as response to water deprivation, response to salt stress, seed germination, and response to hydrogen peroxide pathways. These results may provide valuable insights into the genetic and epigenetic basis of salt tolerance at the seed germination stage, which is important for direct-seeding rice breeding.

Comparative transcriptome analysis of the effects of friction and exogenous gibberellin on germination in Abrus cantoniensis

The seeds of Abrus cantoniensis (A. cantonensis) have dormancy characteristics with very low germination under natural conditions. In general, its seed dormancy could be broken by friction or soaking with exogenous gibberellins (GA₃). To date, the molecular mechanism underlying the effects of GA₃ and friction on its seed germination is unclear. In this study, we tested the effects of different treatments, including soaking in sterile water (G1), friction (G2), soaking in GA₃ (G3), combined treatment of friction, and GA₃ (G4)) on seed germination. Then, we have investigated the seed transcriptome profiles corresponding to the different treatments by RNA sequencing. The results showed that seed germination was significantly increased by combined treatment with friction and GA₃. RNA-Seq analysis generated 84.80 gigabases (Gb) of sequences. 82,996 out of 121,776 unigenes were annotated. Comparative transcriptome analysis observed that 1,130, 1,097, and 708 unigenes were deferentially expressed in G1 vs. G2, G1 vs. G3, and G1 vs. G4 groups, respectively. Additionally, 20 putatively candidate genes related to seed germination, including CYP78A5, Bg7s, GA-20-ox, rd22, MYB4, LEA, CHS, and STH-2, and other potential candidates with abundant expression were identified. Our findings provide first insights into gene expression profiles and physiological response for friction combined with GA₃ on A. cantoniensis seed germination.

Crop Proteomics under Abiotic Stress: From Data to Insights

Food security is a major challenge in the present world due to erratic weather and climatic changes. Environmental stress negatively affects plant growth and development which leads to reduced crop yields. Technological advancements have caused remarkable improvements in crop-breeding programs. Proteins have an indispensable role in developing stress resilience and tolerance in crops. Genomic and biotechnological advancements have made the process of crop improvement more accurate and targeted. Proteomic studies provide the information required for such targeted approaches. The crosstalk among cellular components is being analyzed by subcellular proteomics. Additionally, the functional diversity of proteins is being unraveled by post-translational modifications during abiotic stress. The exploration of precise cellular responses and the networking among different cellular organelles help in the prediction of signaling pathways and protein-protein interactions. High-throughput mass-spectrometry-based protein studies are now possible due to incremental advancements in mass-spectrometry techniques, sample protocols, and bioinformatic tools as well as the increasing availability of plant genome sequence information for multiple species. In this review, the key role of proteomic analysis in identifying the abiotic-stress-responsive mechanisms in various crops was summarized. The development and availability of advanced computational tools were discussed in detail. The highly variable protein responses among different crops have provided a wide avenue for molecular-marker-assisted genetic buildup studies to develop smart, high-yielding, and stress-tolerant varieties to cope with food-security challenges.

Natural variation and domestication selection of ZmSULTR3;4 is associated with maize lateral root length in response to salt stress

Soil salinity is a major constraint that restricts crop productivity worldwide. Lateral roots (LRs) are important for water and nutrient acquisition, therefore understanding the genetic basis of natural variation in lateral root length (LRL) is of great agronomic relevance to improve salt tolerance in cultivated germplasms. Here, using a genome-wide association study, we showed that the genetic variation in ZmSULTR3;4, which encodes a plasma membrane-localized sulfate transporter, is associated with natural variation in maize LRL under salt stress. The transcript of ZmSULTR3;4 was found preferentially in the epidermal and vascular tissues of root and increased by salt stress, supporting its essential role in the LR formation under salt stress. Further candidate gene association analysis showed that DNA polymorphisms in the promoter region differentiate the expression of ZmSULTR3;4 among maize inbred lines that may contribute to the natural variation of LRL under salt stress. Nucleotide diversity and neutrality tests revealed that ZmSULTR3;4 has undergone selection during maize domestication and improvement. Overall, our results revealed a regulatory role of ZmSULTR3;4 in salt regulated LR growth and uncovered favorable alleles of ZmSULTR3;4, providing an important selection target for breeding salt-tolerant maize cultivar.

Multiple forms of vitamin B6 regulate salt tolerance by balancing ROS and abscisic acid levels in maize root

Salt stress causes osmotic stress, ion toxicity and oxidative stress, inducing the accumulation of abscisic acid (ABA) and excessive reactive oxygen species (ROS) production, which further damage cell structure and inhibit the development of roots in plants. Previous study showed that vitamin B6 (VB6) plays a role in plant responses to salt stress, however, the regulatory relationship between ROS, VB6 and ABA under salt stress remains unclear yet in plants. In our study, we found that salt stress-induced ABA accumulation requires ROS production, in addition, salt stress also promoted VB6 (including pyridoxamine (PM), pyridoxal (PL), pyridoxine (PN), and pyridoxal 5'-phosphate (PLP)) accumulation, which involved in ROS scavenging and ABA biosynthesis. Furthermore, VB6-deficient maize mutant small kernel2 (smk2) heterozygous is more susceptible to salt stress, and which failed to scavenge excessive ROS effectively or induce ABA accumulation in maize root under salt stress, interestingly, which can be restored by exogenous PN and PLP, respectively. According to these results, we proposed that PN and PLP play an essential role in balancing ROS and ABA levels under salt stress, respectively, it laid a foundation for VB6 to be better applied in crop salt resistance than ABA.

Salt stress proteins in plants: An overview

Salinity stress is considered the most devastating abiotic stress for crop productivity. Accumulating different types of soluble proteins has evolved as a vital strategy that plays a central regulatory role in the growth and development of plants subjected to salt stress. In the last two decades, efforts have been undertaken to critically examine the genome structure and functions of the transcriptome in plants subjected to salinity stress. Although genomics and transcriptomics studies indicate physiological and biochemical alterations in plants, it do not reflect changes in the amount and type of proteins corresponding to gene expression at the transcriptome level. In addition, proteins are a more reliable determinant of salt tolerance than simple gene expression as they play major roles in shaping physiological traits in salt-tolerant phenotypes. However, little information is available on salt stress-responsive proteins and their possible modes of action in conferring salinity stress tolerance. In addition, a complete proteome profile under normal or stress conditions has not been established yet for any model plant species. Similarly, a complete set of low abundant and key stress regulatory proteins in plants has not been identified. Furthermore, insufficient information on post-translational modifications in salt stress regulatory proteins is available. Therefore, in recent past, studies focused on exploring changes in protein expression under salt stress, which will complement genomic, transcriptomic, and physiological studies in understanding mechanism of salt tolerance in plants. This review focused on recent studies on proteome profiling in plants subjected to salinity stress, and provide synthesis of updated literature about how salinity regulates various salt stress proteins involved in the plant salt tolerance mechanism. This review also highlights the recent reports on regulation of salt stress proteins using transgenic approaches with enhanced salt stress tolerance in crops.

In Situ Observation of Abscisic Acid Distribution in Major Crop Species by Immunofluorescence Labeling

Immunofluorescent approach uses fluorophore-conjugated antibodies to target molecules of interest for the observation of their distribution and microenvironment at cellular or tissue level. In connection with modern fluorescence microscopy, immunofluorescence has high sensitivity and specificity, resulting in a wide range of applications in animal studies. However, the protocols of immunofluorescence are seldom reported. To this end, we describe an optimized protocol for the detection of plant hormone abscisic acid (ABA) in monocot crop species, including maize and rice. By using immunofluorescence technique provided from this protocol, investigation of ABA distribution will continue to deeper our insights in crop developments and stress responses.

Phylogeny and conservation of plant U2A/U2A', a core splicing component in U2 spliceosomal complex

This study systematically identifies 112 U2A genes from 80 plant species by combinatory bioinformatics analysis, which is important for understanding their phylogenetic history, expression profiles and for predicting specific functions. In eukaryotes, a pre-mRNA can generate multiple transcripts by removing certain introns and joining corresponding exons, thus greatly expanding the transcriptome and proteome diversity. The spliceosome is a mega-Dalton ribonucleoprotein (RNP) complex that is essential for the process of splicing. In spliceosome components, the U2 small nuclear ribonucleoprotein (U2 snRNP) forms the pre-spliceosome by association with the branch site. An essential component that promotes U2 snRNP assembly, named U2A, has been extensively identified in humans, yeast and nematodes. However, studies examining U2A genes in plants are scarce. In this study, we performed a comprehensive analysis and identified a total of 112 U2A genes from 80 plant species representing dicots, monocots, mosses and algae. Comparisons of the gene structures, protein domains, and expression patterns of 112 U2A genes indicated that the conserved functions were likely retained by plant U2A genes and important for responses to internal and external stimuli. In addition, analysis of alternative transcripts and splice sites of U2A genes indicated that the fifth intron contained a conserved alternative splicing event that might be important for its molecular function. Our work provides a general understanding of this splicing factor family in terms of genes and proteins, and it will serve as a fundamental resource that will contribute to further mechanistic characterization in plants.

Alteration of proteome in germinating seedlings of piegonpea (Cajanus cajan) after salt stress

Pigeonpea (Cajanus cajan) is an important crop in semi-arid regions and a significant source of dietary proteins in India. The plant is sensitive to salinity stress, which adversely affects its productivity. Based on the dosage-dependent influence of salinity stress on the growth and ion contents in the young seedlings of pigeonpea, a comparative proteome analysis of control and salt stressed (150 mM NaCl) plants was conducted using 7 days-old seedlings. Among various amino acids, serine, aspartate and asparagine were the amino acids that showed increment in the root, whereas serine, aspartate and phenylalanine showed an upward trend in shoots under salt stress. Furthermore, a label-free and gel-free comparative Q-Tof, Liquid Chromatography-Mass spectrometry (LC-MS) revealed total of 118 differentially abundant proteins in roots and shoots with and without salt stress conditions. Proteins related to DNA-binding with one finger (Dof) transcription factor family and glycine betaine (GB) biosynthesis were differentially expressed in the shoot and root of the salinity-stressed seedlings. Exogenous application of choline on GB accumulation under salt stress showed the increase of GB pathway in C. cajan. Gene expression analysis for differentially abundant proteins revealed the higher induction of ethanolamine kinase (CcEthKin), choline-phosphate cytidylyltransferase 1-like (CcChoPh), serine hydroxymethyltransferase (CcSHMT) and Dof protein (CcDof29). The results indicate the importance of, choline precursor, serine biosynthetic pathways and glycine betaine synthesis in salinity stress tolerance. The glycine betaine protects plant from cellular damages and acts as osmoticum under stress condition. Protein interaction network (PIN) analysis demonstrated that 61% of the differentially expressed proteins exhibited positive interactions and 10% of them formed the center of the PIN. Further, The PIN analysis also highlighted the potential roles of the cytochrome c oxidases in sensing and signaling cascades governing salinity stress responses in pigeonpea.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s12298-021-01116-w.

ZmMPK5 phosphorylates ZmNAC49 to enhance oxidative stress tolerance in maize

Mitogen-activated protein kinase (MPK) is a critical regulator of the antioxidant defence system in response to various stimuli. However, how MPK directly and exactly regulates antioxidant enzyme activities is still unclear. Here, we demonstrated that a NAC transcription factor ZmNAC49 mediated the regulation of antioxidant enzyme activities by ZmMPK5. ZmNAC49 expression is induced by oxidative stress. ZmNAC49 enhances oxidative stress tolerance in maize, and it also reduces superoxide anion generation and increases superoxide dismutase (SOD) activity. A detailed study showed that ZmMPK5 directly interacts with and phosphorylates ZmNAC49 in vitro and in vivo. ZmMPK5 directly phosphorylates Thr-26 in NAC subdomain A of ZmNAC49. Mutation at Thr-26 of ZmNAC49 does not affect the interaction with ZmMPK5 and its subcellular localisation. Further analysis found that ZmNAC49 activates the ZmSOD3 expression by directly binding to its promoter. ZmMPK5-mediated ZmNAC49 phosphorylation improves its ability to bind to the ZmSOD3 promoter. Thr-26 of ZmNAC49 is essential for its transcriptional activity. In addition, ZmSOD3 enhances oxidative stress tolerance in maize. Our results show that phosphorylation of Thr-26 in ZmNAC49 by ZmMPK5 increased its DNA-binding activity to the ZmSOD3 promoter, enhanced SOD activity and thereby improved oxidative stress tolerance in maize.

Transcriptome analysis and functional identification of GmMYB46 in soybean seedlings under salt stress

Salinity is one of the major abiotic stress that limits crop growth and productivity. We investigated the transcriptomes of salt-treated soybean seedlings versus a control using RNA-seq to better understand the molecular mechanisms of the soybean (Glycine max L.) response to salt stress. Transcriptome analysis revealed 1,235 differentially expressed genes (DEGs) under salt stress. Several important pathways and key candidate genes were identified by KEGG enrichment. A total of 116 differentially expressed transcription factors (TFs) were identified, and 17 TFs were found to belong to MYB families. Phylogenetic analysis revealed that these TFs may be involved in salt stress adaptation. Further analysis revealed that GmMYB46 was up-regulated by salt and mannitol and was localized in the nucleus. The salt tolerance of transgenic Arabidopsis overexpressing GmMYB46 was significantly enhanced compared to wild-type (WT). GmMYB46 activates the expression of salt stress response genes (P5CS1, SOD, POD, NCED3) in Arabidopsis under salt stress, indicating that the GmMYB46 protein mediates the salt stress response through complex regulatory mechanisms. This study provides information with which to better understand the molecular mechanism of salt tolerance in soybeans and to genetically improve the crop.

Comparative Proteomic Analysis of Tolerant and Sensitive Varieties Reveals That Phenylpropanoid Biosynthesis Contributes to Salt Tolerance in Mulberry

Mulberry, an important woody tree, has strong tolerance to environmental stresses, including salinity, drought, and heavy metal stress. However, the current research on mulberry resistance focuses mainly on the selection of resistant resources and the determination of physiological indicators. In order to clarify the molecular mechanism of salt tolerance in mulberry, the physiological changes and proteomic profiles were comprehensively analyzed in salt-tolerant (Jisang3) and salt-sensitive (Guisangyou12) mulberry varieties. After salt treatment, the malondialdehyde (MDA) content and proline content were significantly increased compared to control, and the MDA and proline content in G12 was significantly lower than in Jisang3 under salt stress. The calcium content was significantly reduced in the salt-sensitive mulberry varieties Guisangyou12 (G12), while sodium content was significantly increased in both mulberry varieties. Although the Jisang3 is salt-tolerant, salt stress caused more reductions of photosynthetic rate in Jisang3 than Guisangyou12. Using tandem mass tags (TMT)-based proteomics, the changes of mulberry proteome levels were analyzed in salt-tolerant and salt-sensitive mulberry varieties under salt stress. Combined with GO and KEGG databases, the differentially expressed proteins were significantly enriched in the GO terms of amino acid transport and metabolism and posttranslational modification, protein turnover up-classified in Guisangyou12 while down-classified in Jisang3. Through the comparison of proteomic level, we identified the phenylpropanoid biosynthesis may play an important role in salt tolerance of mulberry. We clarified the molecular mechanism of mulberry salt tolerance, which is of great significance for the selection of excellent candidate genes for saline-alkali soil management and mulberry stress resistance genetic engineering.

BRASSINOSTEROID-SIGNALING KINASE 1 phosphorylating CALCIUM/CALMODULIN-DEPENDENT PROTEIN KINASE functions in drought tolerance in maize

Drought stress seriously limits crop productivity. Although studies have been carried out, it is still largely unknown how plants respond to drought stress. Here we find that drought treatment can enhance the phosphorylation activity of brassinosteroid-signaling kinase 1 (ZmBSK1) in maize (Zea mays). Our genetic studies reveal that ZmBSK1 positively affects drought tolerance in maize plants. ZmBSK1 localizes in plasma membrane, interacts with calcium/calmodulin (Ca²⁺ /CaM)-dependent protein kinase (ZmCCaMK), and phosphorylates ZmCCaMK. Ser-67 is a crucial phosphorylation site of ZmCCaMK by ZmBSK1. Drought stress enhances not only the interaction between ZmBSK1 and ZmCCaMK but also the phosphorylation of Ser-67 in ZmCCaMK by ZmBSK1. Furthermore, Ser-67 phosphorylation in ZmCCaMK regulates its Ca²⁺ /CaM binding, autophosphorylation and transphosphorylation activity, and positively affects its function in drought tolerance in maize. Our results reveal an important role for ZmBSK1 in drought tolerance and suggest a direct regulatory mode of ZmBSK1 phosphorylating ZmCCaMK.

Structural dynamics and determinants of abscisic acid-receptor binding preference in different aggregation states

In the 21st century, drought has been the main cause of shortages in world grain production and has created problems with food security. Abscisic acid (ABA) is a key plant hormone involved in the response to abiotic stress, especially drought. The pyrabactin resistance (PYR)/PYR1-like (PYL)/regulatory component of abscisic acid receptor (RCAR) family of proteins (simplified as PYLs) is a well-known ABA receptor family, which can be divided into dimeric and monomeric forms. PYLs can recognize ABA and activate downstream plant drought-resistance signals. However, the difference between monomeric and dimeric receptors in the mechanism of the response to ABA is unclear. Here, we reveal that monomeric receptors have a competitive advantage over dimeric receptors for binding to ABA, driven by the energy penalty resulting from dimer dissociation. ABA also plays different roles with the monomer and the dimer: in the monomer, it acts as a 'conformational stabilizer' for stabilizing the closed gate, whereas for the dimer, it serves as an 'allosteric promoter' for promoting gate closure, which leads to dissociation of the two subunits. This work illustrates how receptor oligomerization could modulate hormonal responses and provides a new concept for novel engineered plants based on ABA binding of monomers.

Venn diagrams in bioinformatics

Venn diagrams are widely used tools for graphical depiction of the unions, intersections and distinctions among multiple datasets, and a large number of programs have been developed to generate Venn diagrams for applications in various research areas. However, a comprehensive review comparing these tools has not been previously performed. In this review, we collect Venn diagram generators (i.e. tools for visualizing the relationships of input lists within a Venn diagram) and Venn diagram application tools (i.e. tools for analyzing the relationships between biological data and visualizing them in a Venn diagram) to compare their functional capacity as follows: ability to generate high-quality diagrams; maximum datasets handled by each program; input data formats; output diagram styles and image output formats. We also evaluate the picture beautification parameters of the Venn diagram generators in terms of the graphical layout and briefly describe the functional characteristics of the most popular Venn diagram application tools. Finally, we discuss the challenges in improving Venn diagram application tools and provide a perspective on Venn diagram applications in bioinformatics. Our aim is to assist users in selecting suitable tools for analyzing and visualizing user-defined datasets.