Regulating Plant Development Research Articles

Identification of GiOMT gene family in Glycyrrhiza inflata bat and expression analysis under UV-B stresses

BackgroundO-Methyltransferase (OMTs) is a class of conserved multifunctional enzymes that play important roles in plant developmental regulation, hormone signaling, secondary metabolite synthesis and abiotic stress response. The GiOMT gene family has been identified and analyzed in species such as citrus, alfalfa, Populus and grape, but has not been reported in Glycyrrhiza inflata Bat.ResultsIn this study, we systematically identified and analyzed the GiOMT gene family of G. inflata by bioinformatics, and analyzed their physicochemical properties, conserved motifs, conserved structural domains, gene structures, phylogenetic relationships, chromosomal localization and fragment duplications, and the expression patterns of GiOMT genes in combination with transcriptomic data and qRT-PCR. The results showed that a total of 41 GiOMTs were identified in G. inflata, which were named GiOMT1 ~ GiOMT41 based on their chromosomal locations. Protein characterization showed that 29 GiOMT proteins were hydrophilic and 12 GiOMT proteins were hydrophobic. Subcellular predicted localization revealed that most GiOMT proteins localized in the cytoplasm and chloroplasts. Phylogenetic relationships showed that the OMT genes of three species, G. inflata, Arabidopsis and alfalfa, were distributed in three taxa, while the GiOMT genes were distributed in taxa I and II. Promoters of GiOMT genes contained light responsive element and many hormone responsive elements. The expression levels of GiOMT genes under UV-B stress were varied, indicating that GiOMT gene was in response to abiotic stresses in G. inflata.ConclusionIn this study, we investigated the genome-wide identification, structure, evolution and expression analysis of the GiOMT gene in G. inflata. The basal sequence of GiOMT genes was highly conserved throughout the evolutionary history of G. inflata. Most of the GiOMT genes were highly expressed in roots and were involved in the response to UV-B stress. The GiOMT genes may lead to the accumulation of flavonoids and enhancement of G. inflata quality and drug activity in G. inflata under UV-B radiation.

Ascorbate, as a versatile regulator of plant development: practical implications for enhancing crop productivity, quality, and postharvest storage

Ascorbate, as a versatile regulator of plant development: practical implications for enhancing crop productivity, quality, and postharvest storage

Amide conjugates of the jasmonate precursor cis-OPDA regulate its homeostasis during plant stress responses.

Jasmonates (JAs) are a family of oxylipin phytohormones regulating plant development and growth and mediating 'defense versus growth' responses. The upstream JA biosynthetic precursor cis-(+)-12-oxo-phytodienoic acid (cis-OPDA) acts independently of CORONATIVE INSENSITIVE 1 (COI1)-mediated JA signaling in several stress-induced and developmental processes. However, its perception and metabolism are only partially understood. A few years ago, a low abundant isoleucine analog of the biologically active JA-Ile, OPDA-Ile, was detected years ago in wounded leaves of flowering plants, opening up the possibility that conjugation of cis-OPDA to amino acids might be a relevant mechanism for cis-OPDA regulation. Here, we extended the analysis of amino acid conjugates of cis-OPDA and identified naturally occurring OPDA-Val, OPDA-Phe, OPDA-Ala, OPDA-Glu, and OPDA-Asp accumulating in response to biotic and abiotic stress in Arabidopsis (Arabidopsis thaliana). The OPDA-amino acid conjugates displayed cis-OPDA-related plant responses in a JA-Ile-dependent manner. We also showed that the synthesis and hydrolysis of cis-OPDA amino acid conjugates are mediated by members of the amidosynthetase GRETCHEN HAGEN 3 (GH3) and the amidohydrolase INDOLE-3-ACETYL-LEUCINE RESISTANT 1 (ILR1)/ILR1-like (ILL) families. Thus, OPDA amino acid conjugates function in the catabolism or temporary storage of cis-OPDA in stress responses instead of acting as chemical signals per se.

Role of CLE peptide signaling in root-knot nematode parasitism of plants.

We summarize recent findings that have provided new insights into the mechanisms underlying CLE signaling systems in the regulation of plant development and phytonematode interactions. CLAVATA3/EMBRYO SURROUNDING REGION-RELATED (CLE) peptides are short sequences consisting of 12 or 13 amino acids characterized by hydroxylated proline residues, and their presence has been demonstrated in various plant species and phytonematodes across multiple paralogous genes. Here, we review recently conducted research to understanding the signaling pathway of CLE peptide during plant development and infection caused by phytonematodes. Cell-to-cell communication is important for the coherent functioning of living organisms. CLE peptides combined with their specific transmembrane receptors to induce downstream intracellular signaling pathways shows divergent modes of action in many developmental processes in variable species. Moreover, CLE peptide was also involved in plant disease mechanism caused by various plant parasitic nematodes.

The E3 ubiquitin ligase COP1 and transcription factors HY5 and RHD6 integrate light signaling and root hair development.

Light signaling plays a substantial role in regulating plant development, including the differentiation and elongation of single-celled tissue. However, the identity of the regulatory machine that affects light signaling on root hair cell (RHC) development remains unclear. Here, we investigated how darkness inhibits differentiation and elongation of RHC in Arabidopsis (Arabidopsis thaliana). We found that light promotes the growth and development of RHC. RNA-seq analysis showed that light signaling regulates the differentiation of RHC by promoting the expression of specific genes in the root epidermis associated with cell wall remodeling, JA, auxin, and ethylene signaling pathways. Together, these genes integrate light and phytohormone signals with root hair development. Our investigation also revealed that the core light signal factor ELONGATED HYPOCOTYL 5 (HY5) directly interacts with the key root hair development factor ROOT HAIR DEFECTIVE6 (RHD6), which promotes the transcription of RSL4. However, CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) repressed RHD6 function through the COP1-HY5 complex. Our genetic studies confirm associations between RHD6, HY5, and COP1, indicating that RHD6 largely depends on HY5 for root hair development. Ultimately, our work suggests a central COP1-HY5-RHD6 regulatory module that integrates light signaling and root hair development with several downstream pathways, offering perspectives to decipher single-celled root hair development.

PWOs repress gene transcription by regulating chromatin structures in Arabidopsis.

PWWP-DOMAIN INTERACTOR OF POLYCOMBS (PWO) family proteins play a vital role in regulating plant development. However, the molecular mechanisms of how PWOs regulate chromatin structure is elusive. Our data show that the PWO1 binding sites are enriched with positive modifications but exclusive with H3K27me3. Moreover, PWO1 binds to the H3K27me3-enriched compartment domain (H3K27me3-CD) boundary regions, and functions to maintain the boundary strength. Meanwhile, we found that PWOs and Polycomb repressive complex 2 (PRC2) function parallelly in maintaining H3K27me3-CDs' structure. Loss of either PWOs or PRC2 leads to H3K27me3-CD strength reduction, B to A compartment switching as well as the H3K27me3-CD relocating away from the nuclear periphery. Additionally, PWOs and lamin-like proteins collaborate to regulate multiple chromatin structures to repress gene transcription within H3K27me3-CDs. We conclude that PWOs maintain H3K27me3-CDs' repressive state and regulate their spatial position in the nucleus.

Overexpression of Cassava MeSTP7 Promotes Arabidopsis Seedling Development.

The sugar transporter (STP) gene family is a key regulator of plant development, which is crucial for the efficient transport and utilization of sugars during plant growth and development. In this study, we identified the MeSTP7 gene, which is highly expressed in cassava fibrous roots, early storage roots, and under hormonal treatment, including IAA, MeJA, ABA, and GA3, and abiotic stressors, such as mannitol and NaCl. A strong response was observed with exoqenous IAA. Transfecting MeSTP7 into Arabidopsis promoted early seedling growth, particularly in lateral root development. The content of endogenous hormones (IAA and MeJA) as well as soluble sugars (sucrose, fructose, and glucose) was elevated in transgenic Arabidopsis. Hormone treatments with IAA, MeJA, GA3, and ABA on transgenic Arabidopsis revealed that transgenic Arabidopsis responded positively to added 20 μM IAA. They also exhibited co-induced regulation of lateral root formation by GA3, MeJA, and ABA. qRT-PCR analysis showed that overexpression of MeSTP7 upregulated the expression of IAA14, ARF7, and ARF19 in Arabidopsis. Under IAA treatment, the expression of these genes was similarly upregulated but downregulated under MeJA treatment. These results suggest that MeSTP7 may promote Arabidopsis seedling development by increasing the content of sucrose, glucose, and fructose in roots, which in turn influences IAA-based hormonal signaling.

The loss-of-function of AtNATA2 enhances AtADC2-dependent putrescine biosynthesis and priming, improving growth and salinity tolerance in Arabidopsis.

Putrescine (Put) is a promising small molecule-based biostimulant to enhance plant growth and resilience, though its mode of action remains unclear. This study investigated the Put priming effect on Arabidopsis mutant lines (Atadc1, Atadc2, Atnata1, and Atnata2) under control conditions and salinity to understand its role in regulating plant growth. The Atadc2 mutant, characterized by reduced endogenous Put levels, showed insensitivity to Put priming without growth enhancement, which was linked to significant imbalances in nitrogen metabolism, including a high Gln/Glu ratio. Contrarily, the Atnata2 mutant exhibited significant growth improvement and upregulated AtADC2 expression, particularly under Put priming, highlighting these genes' involvement in regulating plant development. Put priming enhanced plant growth by inducing the accumulation of specific polyamines (free, acetylated, conjugated, or bound form) and improving light-harvesting efficiency, particularly in the Atnata2 line. Our findings suggest that AtNATA2 may negatively regulate Put synthesis and accumulation via AtADC2 in the chloroplast, impacting light harvesting in photosystem II (PSII). Furthermore, the Atadc2 mutant line exhibited upregulated AtADC1 but reduced AcPut levels, pointing to a cross-regulation among these genes. The regulation by AtNATA2 on AtADC2 and AtADC2 on AtADC1 could be crucial for plant growth and overall stress tolerance by interacting with polyamine catabolism, which shapes the plant metabolic profile under different growth conditions. Understanding the regulatory mechanisms involving crosstalk between AtADC and AtNATA genes in polyamine metabolism and the connection with certain SMBBs like Put can lead to more effective agricultural practices, improving plant growth, nitrogen uptake, and resilience under challenging conditions.

Research on the Mechanisms of Phytohormone Signaling in Regulating Root Development.

Phytohormones are organic compounds produced in trace amounts within plants that regulate their physiological processes. Their physiological effects are highly complex and diverse. They influence processes ranging from cell division, elongation, and differentiation to plant germination and rooting. Therefore, phytohormones play a crucial regulatory role in plant growth and development. Recently, various studies have highlighted the role of PHs, such as auxin, cytokinin (CK), and abscisic acid (ABA), and newer classes of PHs, such as brassinosteroid (BR) and peptide hormone, in the plant responses toward environmental stresses. These hormones not only have distinct roles at different stages of plant growth but also interact to promote or inhibit each other, thus effectively regulating plant development. Roots are the primary organs for water and mineral absorption in plants. During seed germination, the radicle breaks through the seed coat and grows downward to form the primary root. This occurs because the root needs to quickly penetrate the soil to absorb water and nutrients, providing essential support for the plant's subsequent growth. Root development is a highly complex and precisely regulated process influenced by various signals. Changes in root architecture can affect the plant's ability to absorb nutrients and water, which in turn impacts crop yield. Thus, studying the regulation of root development is of great significance. Numerous studies have reported on the role of phytohormones, particularly auxins, in root regulation. This paper reviews recent studies on the regulation of root development by various phytohormones, both individually and in combination, providing a reference for researchers in this field and offering perspectives on future research directions for improving crop yields.

WOX1 controls leaf serration development via temporally restricting BZR1 and CUC3 expression in Arabidopsis.

Leaves evolve shape diversity ranging from simple leaves with smooth margin to complicated shape with toothed/serrated, lobed and dissected leaves with leaflets. In the model plant Arabidopsis thaliana with simple leaves producing serrated margin, boundary regulatory factors CUP SHAPED COTYLEDON 2 (CUC2) and CUC3 play important roles in promoting leaf serration initiation and maintenance. Stem cell related WUSCHEL-RELATED HOMEOBOX1 (WOX1) and PRESSED FLOWER/WOX3 are also essential for leaf margin morphogenesis, but the role of WOX1 and PRS as well as the relationships between CUCs and WOXs on tooth development was unclear. In this study, we found that WOX1, but not PRS, prevents overproduction of tooth number and excessive tooth size by limiting CUC3 expression to a moderate level in a temporally regulated manner. We also revealed that BRASSINAZOLE RESISTANT 1 (BZR1), a known regulator for plant development including boundary regions, is involved in WOX1 negative regulation of tooth development by repressing CUC3 expression during the initiation/early stage of tooth development. WOX1 parallelly limits BZR1 and CUC3 expression from the late stage of the first 2 teeth, while restricts CUC3 activity in a BZR1 dependent manner from the initiation/early stage of subsequently developed teeth. This study uncovers a new mechanism for WOX1 in fine-tuning the leaf margin geometry.

Sulfated peptides: key players in plant development, growth, and stress responses.

Peptide hormones regulate plant development, growth, and stress responses. Sulfated peptides represent a class of proteins that undergo posttranslational modification by tyrosylprotein sulfotransferase (TPST), followed by specific enzymatic cleavage to generate mature peptides. This process contributes to the formation of various bioactive peptides, including PSKs (PHYTOSULFOKINEs), PSYs (PLANT PEPTIDE CONTAINING SULFATED TYROSINE), CIFs (CASPARIAN STRIP INTEGRITY FACTOR), and RGFs (ROOT MERISTEM GROWTH FACTOR). In the past three decades, significant progress has been made in understanding the molecular mechanisms of sulfated peptides that regulate plant development, growth, and stress responses. In this review, we explore the sequence properties of precursors, posttranslational modifications, peptide receptors, and signal transduction pathways of the sulfated peptides, analyzing their functions in plants. The cross-talk between PSK/RGF peptides and other phytohormones, such as brassinosteroids, auxin, salicylic acid, abscisic acid, gibberellins, ethylene, and jasmonic acid, is also described. The significance of sulfated peptides in crops and their potential application for enhancing crop productivity are discussed, along with future research directions in the study of sulfated peptides.

Genome-Wide Identification and Expression Analysis of the ALKB Homolog Gene Family in Potato (Solanum tuberosum L.).

N6-methyladenosine (m6A) is an abundant and pervasive post-transcriptional modification in eukaryotic mRNAs. AlkB homolog (ALKBH) proteins play crucial roles in RNA metabolism and translation, participating in m6A methylation modification to regulate plant development. However, no comprehensive investigations have been conducted on ALKBH in potato. Here, 11 StALKBH family genes were identified in potato and renamed according to BLASTP and phylogenetic analyses following the Arabidopsis genome. The characteristics, sequence structures, motif compositions, phylogenetics, chromosomal locations, synteny, and promoter cis-acting element predictions were analyzed, revealing distinct evolutionary relationships between potato and other species (tomato and Arabidopsis). Homologous proteins were classified into seven groups depending on similar conserved domains, which implies that they possess a potentially comparable function. Moreover, the StALKBHs were ubiquitous, and their expression was examined in the various tissues of a whole potato, in which the StALKBH genes, except for StALKBH2, were most highly expressed in the stolon and flower. Multiple hormone and stress-response elements were found to be located in the promoters of the StALKBH genes. Further qRT-PCR results suggest that they may be significantly upregulated in response to phytohormones and abiotic stress (except for cold), and the expression of most of the StALKBH genes exhibited positively modulated trends. Overall, this study is the first to report a genome-wide assessment of the ALKBH family in potato, providing valuable insights into candidate gene selection and facilitating in-depth functional analyses of ALKBH-mediated m6A methylation mechanisms in potato.

Genome-wide Association Studies of Photosynthetic and Agronomic Traits in Cowpea Collection.

Exploring genomic regions linked with drought tolerance and photosynthesis in cowpea could accelerate breeding of climate-resilient cowpea varieties A Genome-wide association study (GWAS) was conducted to identify marker-trait associations for agronomic and photosynthetic traits measured under well-watered and water-stressed conditions. One hundred and twelve cowpea accessions from IITA were phenotyped for agronomic and photosynthetic traits across three locations in two years: Ibadan, Ikenne (2020 and 2021) and Kano (2021 and 2022). The accessions were genotyped using 19,000 DArT-Seq SNP markers from which 9,210 markers were utilized for GWAS analysis using BLINK and mixed linear model (MLM) in GAPIT. Results revealed significant accession × environment interactions for measured traits while ΦPSII, ΦNO and ΦNPQ had significant and consistent correlations with grain yield across conditions. GWAS identified five SNP markers having consistent associations with grain yield under well-watered and water-stressed conditions and three markers associated with ΦNPQ and ΦNO. Gene annotations revealed Vigun04g169000 and Vigun08g168900 genes linked with grain yield and highly expressed under water-stressed conditions have functional roles in regulating plant development and adaptive response to environmental stress. Vigun07g133400, Vigun07g132700 and Vigun07g258000 genes linked with ΦNPQ and ΦNO are involved in activities controlling photoprotection and stress-induced damage in plants. This study identified natural genetic variation in cowpea and correlations between photosynthetic traits and grain yield under real-field drought conditions. The identified SNP markers upon validation would be valuable in marker-assisted selection and useful for cowpea breeders to harness the role of photosynthesis in genetic enhancement of cowpea tolerance to drought.

Chloroplast elongation factors break the growth-immunity trade-off by simultaneously promoting yield and defence.

Chloroplasts regulate plant development and immunity. Here we report that potato chloroplast elongation factors StTuA and StTuB, targeted by Phytophthora infestans RXLR effector Pi22926, positively regulate immunity and growth. Plants expressing Pi22926, or silenced for TuA/B, show increased P. infestans susceptibility and decreased photosynthesis, plant growth and tuber yield. By contrast, StTuA/B overexpression reduces susceptibility, elevates chloroplast-derived reactive oxygen species production and increases photosynthesis and potato tuber yield by enhancing chloroplast protein translation. Another plant target of Pi22926, StMAP3Kβ2, interacts with StTuB, phosphorylating it to promote its translocation into chloroplasts. However, Pi22926 attenuates StTuB association with StMAP3Kβ2 and phosphorylation. This reduces StTuB translocation into chloroplasts, leading to its proteasome-mediated turnover in the cytoplasm. We uncover new mechanisms by which a pathogen effector inhibits immunity by disrupting key chloroplast functions. This work shows that StTuA/B break the growth-immunity trade-off, promoting both disease resistance and yield, revealing the enormous potential of chloroplast biology in crop breeding.

Diversification and conservation of DNA binding specificities of SPL family of transcription factors.

SQUAMOSA Promoter-Binding Protein-Like (SPL) transcription factors play vital roles in plant development and stress responses. In this study, we report a comprehensive DNA Affinity Purification sequencing (DAP-seq) analysis for 14 of the 16 SPL transcription factors in Arabidopsis thaliana, providing valuable insights into their DNA-binding specificities. We performed Gene Ontology (GO) analysis of the target genes to reveal their convergent and diverse biological functions among SPL family proteins. Comparative analysis between the paralogs AtSPL9 and AtSPL15 revealed differences in their binding motifs, suggesting divergent regulatory functions. Additionally, we expanded our investigation to homologs of AtSPL9/15 in Zea mays (ZmSBP8/30) and Triticum aestivum (TaSPL7/13), identifying conserved and unique DNA-binding patterns across species. These findings provide key resources for understanding the molecular mechanisms of SPL transcription factors in regulating plant development and evolution across different species.

R-Methylation in Plants: A Key Regulator of Plant Development and Response to the Environment.

Although arginine methylation (R-methylation) is one of the most important post-translational modifications (PTMs) conserved in eukaryotes, it has not been studied to the same extent as phosphorylation and ubiquitylation. Technical constraints, which are in the process of being resolved, may partly explain this lack of success. Our knowledge of R-methylation has recently evolved considerably, particularly in metazoans, where misregulation of the enzymes that deposit this PTM is implicated in several diseases and cancers. Indeed, the roles of R-methylation have been highlighted through the analyses of the main actors of this pathway: the PRMT writer enzymes, the TUDOR reader proteins, and potential "eraser" enzymes. In contrast, R-methylation has been much less studied in plants. Even so, it has been shown that R-methylation in plants, as in animals, regulates housekeeping processes such as transcription, RNA silencing, splicing, ribosome biogenesis, and DNA damage. R-methylation has recently been highlighted in the regulation of membrane-free organelles in animals, but this role has not yet been demonstrated in plants. The identified R-met targets modulate key biological processes such as flowering, shoot and root development, and responses to abiotic and biotic stresses. Finally, arginine demethylases activity has mostly been identified in vitro, so further studies are needed to unravel the mechanism of arginine demethylation.

N6-methyladenosine transcriptome-wide profiles of maize kernel development.

Maize (Zea mays L.) kernel development is a complex and dynamic process involving cell division and differentiation, into a variety of cell types. Epigenetic modifications, including DNA methylation, play a pivotal role in regulating this process. N6-methyladenosine modification is a universal and dynamic post-transcriptional epigenetic modification that is involved in the regulation of plant development. However, the role of N6-methyladenosine in maize kernel development remains unknown. In this study, we have constructed transcriptome-wide profiles for maize kernels at various stages of early development. Utilizing a combination of MeRIP-seq and RNA-seq analysis, we identified a total of 11,170, 10,973, 11,094, 11,990, 12,203 and 10,893 N6-methyladenosine peaks in maize kernels at 0, 2, 4, 6, 8, and 12 days after pollination, respectively. These N6-methyladenosine modifications were primarily deposited at the 3'-UTRs and were associated with the conserved motif-UGUACA. Additionally, we found that conserved N6-methyladenosine modification are involved in the regulation of genes that are ubiquitously expressed during kernel development. Further analysis revealed that N6-methyladenosine peak intensity was negatively correlated with the mRNA abundance of these ubiquitously expressed genes. Meanwhile, we employed phylogenetic analysis to predict potential regulatory proteins involved in maize kernels development and identified several that participate in the regulation of N6-methyladenosine modifications. Collectively, our results suggest the existence of a novel post-transcriptional epigenetic modification mechanism involved in the regulation of maize kernels development, thereby providing a novel perspective for maize molecular breeding.

A cold-inducible MYB like transcription factor, CsHHO2, positively regulates chilling tolerance of cucumber fruit by enhancing CsGR-RBP3 expression

Plant HRS1 (hypersensitive to low phosphate (Pi)-elicited primary root shortening 1) and its homologs have been primarily characterized in Pi and nitrogen responses. However, their regulatory roles in cold responses remain largely unexplored. Here, we characterized the functional roles of HRS1 homolog 2 (CsHHO2) in regulating cold resistance in harvested cucumber fruit and examined the dependency of the role on glycine-rich RNA-binding protein 3 (CsGR-RBP3) gene expression. Cold treatments strongly induced CsHHO2 expression in cucumber fruit. GUS staining and expression analysis revealed that cold treatment stimulated CsHHO2 expression, at least partially, by enhancing the promoter activity. Subcellular localization results indicated that the green fluorescent protein (GFP)-tagged CsHHO2 proteins were localized to both the nucleus and the cytoplasm (potentially the plasma membrane), with confirmed nuclear localization when co-overexpressed with mCherry. Reducing CsHHO2 expression in cucumber fruit through VIGS significantly compromised the chilling tolerance, while its overexpression in cucumber fruit and Arabidopsis plants enhanced cold tolerance. The results of electrophoretic mobility shift assay (EMSA), yeast one-hybrid (Y1H) assay and dual-luciferase reporter (DLR) assay indicated that CsHHO2 specifically bound to the promoter of CsGR-RBP3, and enhanced its transcription. Transcriptomic analysis indicated that most differentially expressed genes (DEGs) modulated by CsHHO2 and CsGR-RBP3 proteins were identical, and the common DEGs were mainly enriched in several stress defense pathways, such as plant-pathogen interaction, phenylpropanoid biosynthesis, and plant hormone signal transduction. Functional complementation analysis of CsHHO2 and CsGR-RBP3 in cucumber fruit revealed that CsGR-RBP3 expression were indispensable for CsHHO2-modulated cold resistance. These results collectively suggest that CsHHO2, activated by cold signals, positively regulates the chilling tolerance of cucumber fruit by enhancing CsGR-RBP3 expression. Overall, this work suggests CsHHO2 as a key regulator of cold tolerance in cucumber fruit, provides key genetic resources for breeding cold-resistant cucumbers, and sheds novel insight into the roles of HRS1 family members in regulating plant development under environmental stresses.

Molecular dialogue between light and temperature signaling in plants: From perception to thermotolerance.

Light and temperature are the two most variable environmental signals, which significantly regulate plant growth and development. Plants in the natural environment usually encounter warmer temperatures during the day and cooler temperatures at night, suggesting both light and temperature are closely linked signals. Due to global warming, it has become important to understand how light and temperature signaling pathways converge, and regulate plant development. This review outlines diverse mechanisms of light and temperature perception and downstream signaling, with an emphasis on their integration and interconnection. The recent research has highlighted the regulation of thermomorphogenesis by photoreceptors and their downstream light signaling proteins under different light conditions, and circadian clock components at warm temperatures. We have made an attempt to comprehensively describe these studies and demonstrate their connection with plant developmental responses. We have also explained how gene signaling pathways of light and thermomorphogenesis, are interconnected with HSR-mediated thermotolerance, which reveals new avenues to manipulate plants for climate resilience. In addition, the role of sugars as signaling molecules between light and temperature is also highlighted. Thus, we envisage that such detailed knowledge will enhance the understanding of how plants perceive light and temperature cues simultaneously and bring about responses that help in their adaptation.

Promoter role of putrescine for molecular and biochemical processes under drought stress in barley

Drought, which adversely affects plant growth and continuity of life and reduces product yield and quality, is one of the most common abiotic stresses at the globally. One of the polyamines that regulates plant development and reacts to abiotic stressors, including drought stress, is Putrescine (Put). This study compared the physiological and molecular effects of applying exogenous Put (10 µM) to barley (Hordeum vulgare cv. Burakbey) under drought stress (− 6.30 mPa PEG 6000). The 21-day drought stress imposed on the barley plant had a strong negative effect on plant metabolism in all experimental groups. Exogenous Put treatment under drought stress had a reformative effect on the cell cycle (transitions from G0-G1 to S and from S to G2-M), total protein content (almost 100%), endogenous polyamine content, malondialdehyde (MDA) (70%), and ascorbate peroxidase (APX) (62%) levels compared to the drought stress plants. Superoxide dismutase (SOD) (12%) and catalase (CAT) (32%) enzyme levels in the same group increased further after exogenous Put application, forming a response to drought stress. Consequently, it was discovered that the administration of exogenous Put in barley raises endogenous polyamine levels and then improves drought tolerance due to increased antioxidant capability, cell division stimulation, and total protein content.