Leaf spots caused by Curvularia lunata infection pose a significant threat to global maize production. Although resistance gene breeding faces challenges due to pathogen evolution, the plant microbiome has emerged as a key modulator of disease resistance. However, the mechanisms via which plant genes regulate phyllosphere metabolites to recruit beneficial microbes remain poorly understood. Here, we combined gene mapping, metabolomics, microbiome analyses, cytological analysis, and in vitro and in vivo experiments to investigate the disease resistance mechanism of ZmHPATR1. We first identified that the loss-of-function mutation in ZmHPATR1 significantly increased the levels of fumaric acid, folic acid, and tetrahydrofolic acid in the leaves, leading to the enrichment of the genus Sphingomonas. We further demonstrated that the extracellular polysaccharide, welan gum, biosynthesized by Sphingomonas, effectively inhibited C. lunata growth and disrupted its cell structure. These results enable us to comprehensively understand the complicated mechanisms of plant resistance to disease through a four-level regulatory network that links plant genes, metabolites, microbes, and pathogens. Our findings provide new strategies for targeted microbiome-based disease-resistant breeding and the development of novel biopesticides for maize.
Cadmium (Cd) in agricultural soils readily accumulates in crop grains and shoots, posing serious risks to food and feed safety, especially in maize (Zea mays L.). Natural resistance-associated macrophage proteins (NRAMPs) constitute a key family of metal transporters; however, their role in Cd uptake in maize remains unclear. In this study, the maize gene ZmNRAMPL5 mediated Cd uptake when expressed in yeast. ZmNRAMPL5 knockout mutants, which exhibited no differences from wild type under normal conditions but showed reduced Cd accumulation, alleviated toxicity, increased tolerance under Cd stress. Pot experiments under simulated light and moderate Cd-contaminated soils further showed that knockout lines maintained silage biomass and exhibited over 60% and 80% increases in grain yield per ear compared with wild type, respectively. Moreover, Cd concentrations in stems, leaves, and grains of knockout lines were significantly reduced and remained well below China’s national safety thresholds. Thus, ZmNRAMPL5 might be used in developing Cd-tolerant, low-Cd maize germplasm for grain and feed production in Cd-contaminated farmlands.
The precise enhancement of nutritional quality in silage maize is a core strategy for increasing livestock production efficiency. Through evolutionary analysis of multiple plant species, we identified two functionally synergistic upstream open reading frames (uORF1 and uORF2) within the 5' untranslated region of the gene encoding GDP-L-galactose phosphorylase (GGP). By leveraging a natural translation-enhancing haplotype of uORF1 (Hap2) and performing CRISPR/Cas9-mediated targeted mutagenesis of the highly conserved uORF2, we successfully engineered an elite dual-uORFs variant. This variant significantly increased vitamin C (Vc) content and concurrently improved key silage quality traits, including crude protein and phosphorus levels, without inducing growth penalties. Transcriptomic profiling further elucidated the molecular mechanisms by which the dual-uORFs variation coordinately regulates Vc biosynthesis and the improvement of silage quality. Our findings deepen the understanding of the conventional paradigm of single-uORF regulation and provide a novel strategy and superior germplasm resources for the precision breeding of high-Vc, high-quality silage maize.
5-Aminolevulinic acid (ALA) is widely applied in agriculture, animal husbandry, medicine, and often manufactured in Escherichia coli for overexpressing ALA synthase (ALAS) from α-proteobacteria. For enhancing extracellular ALA production, several approaches have been exploited. Here, we developed and identified a new combination strategy to increase ALA production in E. coli, including selection of the negatively-charged peptide tag as a C-terminal fusion partner for increasing soluble production of the ALAS codon variant from Rhodobacter sphaeroides, mutation of certain residues to increase the ALAS variant activity, optimization of the signal sequences to facilitate ALA secretion, down-regulation of the hemB to inhibit ALA transformation in one plasmid expression system, and supply of 4 mM dithiothreitol to the culture to increase cells tolerant to the oxidative stress. Under the specified cultural conditions, ALA yield was up to 3.2 g/L in flash flasks. Compared with the added cadmium-induced stress, simultaneous supply of purified ALA improved maize seedlings growth, decreased contents of malondialdehyde and hydrogen peroxide, and increased peroxidase activity, contents of chlorophylls and proline.
Previously, we identified the human annexin A1 as a purification tag for column-free purification with gentler calcium-responsive precipitation. In this work, we used the annexin A1 tagged green fluorescent protein constructs for detecting extracellular production in Escherichia coli, Bacillus subtilis, and Pichia pastoris, and identified that the leaderless fusion protein was transported extracellularly in E. coli with supply of additives including Triton X-100. The coexpressed enzymes, culture compositions, and induction conditions in E. coli extracellular expression systems were optimized. With coexpression of phospholipase C from Bacillus cereus and addition of 0.2 % Triton X-100 after induction for 60 h at 28 °C, the annexin A1 tagged green fluorescent protein and 5-aminolevulinate dehydratase from E. coli were overexpressed and purified from lysogeny broth by precipitation with 20 mM Ca2+ and redissolution with 25 mM EDTA with the acceptable protein purities and recoveries. The silica binding peptide was fused to the annexin A1 tagged fluorescent protein fusion for successive affinity precipitation and purification. With incubation of the specific protease, the released tag-free protein displayed higher purity via on-resin cleavage than that through cleavage of the free fusion protein. The tandem tag is applicable for two-step purification of small or large amounts of other fusion proteins in the culture and recovery of tag-free proteins at low cost.
Drought stress often affects crop growth and even causes crop death, while aquaporins can maintain osmotic balance by transporting water across membranes, so it is important to study how to improve drought tolerance of crops by using aquaporins. In this work, we characterize a set of subfamily members named NIPs belonging to the family of aquaporins in Lotus japonicus, grouping 14 family members based on the sequence similarity in the aromatic/arginine (Ar/R) region. Among these members, LjNIP1;5 is one of the genes with the highest expression in roots which is induced by the AM fungus. In Lotus japonicus, LjNIP1;5 is highly expressed in symbiotic roots, and its promoter can be induced by drought stress and AM fungus. Root colonization analysis reveals that ljnip1:5 mutant exhibits lower mycorrhizal colonization than the wild type, with increasing the proportion of large arbuscule, and fewer arbuscule produced by symbiosis under drought stress. In the LjNIP1;5OE plant, we detected a strong antioxidant capacity compared to the control, and LjNIP1;5OE showed higher stem length under drought stress. Taken together, the current results facilitate our comprehensive understanding of the plant adaptive to drought stress with the coordination of the specific fungi.
The growth and development of maize (Zea mays L.) are significantly impeded by prolonged exposure to high temperatures. Heat stress transcription factors (HSFs) play crucial roles in enabling plants to detect and respond to elevated temperatures. However, the genetic mechanisms underlying the responses of HSFs to heat stress in maize remain unclear. Thus, we aimed to investigate the role of ZmHSFA2B in regulating heat tolerance in maize. Here, we report that ZmHSFA2B has two splicing variants, ZmHSFA2B-I and ZmHSFA2B-II. ZmHSFA2B-I encodes full-length ZmHSFA2B (ZmHSFA2B-I), whereas ZmHSFA2B-II encodes a truncated ZmHSFA2B (ZmHSFA2B-II). Overexpression of ZmHSFA2B-I improved heat tolerance in maize and Arabidopsis thaliana, but it also resulted in growth retardation as a side effect. RNA-sequencing and CUT&Tag analyses identified ZmMBR1 as a putative target of ZmHSFA2B-I. Overexpression of ZmMBR1 also enhanced heat tolerance in Arabidopsis. ZmHSFA2B-II was primarily synthesized in response to heat stress and competitively interacted with ZmHSFA2B-I. This interaction consequently reduced the DNA-binding activities of ZmHSFA2B-I homodimers to the promoter of ZmMBR1. Subsequent investigations indicate that ZmHSFA2B-II limits the transactivation and tempers the function of ZmHSFA2B-I, thereby reducing the adverse effects of excessive ZmHSFA2B-I accumulation. Based on these observations, we propose that the alternative splicing of ZmHSFA2B generates a self-regulatory loop that fine-tunes heat stress response in maize.
Diaminopropionate ammonia-lyase transforms D and L isomers of 2,3-diaminopropionate to pyruvate and ammonia. It catalyzes D- and l-serine less effectively. L-2,3-diaminopropionate is a precursor in the biosynthesis of oxalyl diaminopropionate as a neurotoxin in certain legume species. In this work, we cyclized the diaminopropionate ammonia-lyase from Salmonella typhimurium in vitro using the redox-responsive split intein, and identified that backbone cyclization afforded the enzyme with the improved activity, thermal stability and resistance to the exopeptidase proteolysis, different from effects of the incorporated sequence recognized by tobacco vein mottling virus protease at C-terminus. Using analyses of three fluorescent dyes including 8-anilino-1-naphthalenesulfonic acid, N-phenyl-1-naphthylamine, and thioflavin T, the same amounts of the cyclic protein displayed less fluorescence than those of the linear protein upon the heat treatment. The cyclic enzyme displayed the enhanced activity in Escherichia coli cells using the designed novel reporter. In this system, d-serine was added to the culture and transported into the cytoplasm. It was transformed by pre-overexpression of the diaminopropionate ammonia-lyase, and untransformed d-serine was oxidized by the coproduced human d-amino acid oxidase to generate hydrogen peroxide. This oxidant is monitored by the HyPer indicator. The current results presented that the cyclized enzyme could be applied as a better candidate to block the neurotoxin biosynthesis in certain plant species.
Objective: We compared the MeltPro assay to whole-genome sequencing (WGS) to investigate the molecular characterization of second-line injectable drug (SLID) resistance in multidrug-resistant tuberculosis (MDR-TB) isolates in Chongqing, China. Methods: A total of 122 MDR-TB patient isolates were collected between March 2019 and June 2020 from Chongqing Municipality, China. Conventional drug-susceptibility testing was performed using the proportion method, followed to generate minimum inhibitory concentrations (MICs) of SLIDs determined by microplate alamarblue assay. All strains were subjected to both MeltPro and WGS assays. Results: Among 122 MDR-TB isolates, 30 (24.6%), 22 (18.0%), and 14 (11.5%) were resistant to kanamycin (KM), amikacin (AM), and capreomycin (CM), respectively. Of the 31 SLID-resistant isolates, 24 (77.4%, 24/31) isolates harbored mutations in the rrs gene, with the most prevalent mutations in rrs A1401G (22/24, 91.7%). Mutation in rrs A1401G was associated with high levels of resistance to KM (MIC, >= 40 mu g/mL) and AM (MIC, >= 64 mu g/mL), but disparities in CM-resistance levels. Using phenotypic drug-susceptibility testing as gold standard, we found that the overall sensitivity of MeltPro and WGS was 87.1% and 90.32% and specificity 100% and 97.8%, respectively. Seven isolates had discordant results between phenotypic and genotypic resistance of SLIDs. Conclusion: MeltPro is a promising diagnostic tool for accurate identification of SLID-resistant MTB isolates with mutations in the rrs and eis genes. There was a disparity between MeltPro with WGS results in the proportion of heterogeneous drug-resistant bacteria with rrs mutation and limited probes. Resistance mechanisms other than genetic mutations will affect the consistency of MeltPro and WGS with phenotypic drug-susceptibility results.
Flavin mononucleotide-binding proteins or domains emit cyan-green fluorescence under aerobic and anaerobic conditions, but relatively low fluorescence and less thermostability limit their application as reporters. In this work, we incorporated the codon-optimized fluorescent protein from Chlamydomonas reinhardtii with two different linkers independently into the redox-responsive split intein construct, overexpressed the precursors in hyperoxic Escherichia coli SHuffle T7 strain, and cyclized the target proteins in vitro in the presence of the reducing agent. Compared with the purified linear protein, the cyclic protein with the short linker displayed enhanced fluorescence. In contrast, cyclized protein with incorporation of the long linker including the myc-tag and human rhinovirus 3C protease cleavable sequence emitted slightly increased fluorescence compared with the protein linearized with the protease cleavage. The cyclic protein with the short linker also exhibited increased thermal stability and exopeptidase resistance. Moreover, induction of the target proteins in an oxygen-deficient culture rendered fluorescent E. coli BL21 (DE3) cells brighter than those overexpressing the linear construct. Thus, the cyclic reporter can hopefully be used in certain thermophilic anaerobes.
BACKGROUND:Several fusion tags for separation handle have been developed, but the fused tag for simply and cheaply separating the target protein is still lacking.RESULTS:Separation conditions for the human annexin A1 (hanA1) tagged emerald green fluorescent protein (EmGFP) in Escherichia coli were optimized via precipitation with calcium chloride (CaCl2) and resolubilization with ethylenediamine tetraacetic acid disodium salt (EDTA-Na2). The HanA1-EmGFP absorbing with other three affinity matrix was detected, only it was strongly bound to heparin Sepharose. The separation efficiency of the HanA1-EmGFP was comparable with purification efficiency of the His6-tagged HanA1-EmGFP via metal ion affinity chromatography. Three fluorescent proteins for the EmGFP, mCherry red fluorescent protein and flavin-binding cyan-green fluorescent protein LOV from Chlamydomonas reinhardtii were used for naked-eye detection of the separation and purification processes, and two colored proteins including a red protein for a Vitreoscilla hemoglobin (Vhb), and a brown protein for maize sirohydrochlorin ferrochelatase (mSF) were used for visualizing the separation process. The added EDTA-Na2 disrupted the Fe-S cluster in the mSF, but it showed little impact on heme in Vhb.CONCLUSIONS:The selected five colored proteins were efficient for detecting the applicability of the highly selective hanA1 for fusion separation and purification handle. The fused hanA1 tag will be potentially used for simple and cheap affinity separation of the target proteins in industry and diagnosis.
To expand the reported redox-dependent intein system application, in this work, we used the split intein variant with highly trans-splicing efficiency and minimal extein dependence to cyclize the green fluorescent protein variant reporter in vitro. The CPG residues were introduced adjacent to the intein's catalytic cysteine for reversible formation of a disulfide bond to retard the trans-splicing reaction under the oxidative environment. The cyclized reporter protein in Escherichia coli cells was easily prepared by organic extraction and identified by the exopeptidase digestion. The amounts of extracted cyclized protein reporter in BL21 (DE3) cells were higher than those in hyperoxic SHuffle T7 coexpression system for facilitating the disulfide bond formation. The double His6-tagged precursor was purified for in vitro cyclization of the protein for 3 h. Compared with the purified linear counterpart, the cyclic reporter showed about twofold increase in fluorescence intensity, exhibited thermal and hydrolytic stability, and displayed better folding efficiency in BL21 (DE3) cells at the elevated temperature. Taken together, the developed redox-dependent intein system will be used for producing other cyclic disulfide free proteins. The cyclic reporter is a potential candidate applied in certain thermophilic aerobes.
Several fusion tags have been developed for non-chromatographic fusion protein purification. Previously, we iden-tified that human annexin A1 as a novel N-terminal purification tag was used for purifying the fusion proteins produced in Escherichia coli through precipitation in 10 mM Ca2D buffer, and redissolution of the precipitate in 15 mM EDTA buffer. In this work, we selected four metal-dependent enzymes including E. coli 5-aminolevulinate dehydratase, yeast 3-hydroxyanthranilate 3,4-dioxygenase, maize serine racemase and copper amine oxidase for investigating the annexin A1 tag applicability. Fusion of the His6-tag or the enzyme changed the behavior of precipitation-redissolution. The relatively high recovery yields of three tagged enzymes with the improved purities were obtained through two rounds of purification, whereas low recovery yield of the annexin A1 tagged maize amine oxidase was prepared. The added EDTA displayed different abilities to redissolve the fusion proteins precipitates in two precipitation-redissolution cycles. It inactivated three enzymes and obviously inhibited the activity of the fused maize serine racemase. Based on current findings, we believe that four enzymes could be applied for evaluating applicability of the proteins or peptides as affinity tags for chromatographic purification in a calcium dependent manner.(c) 2023, The Society for Biotechnology, Japan. All rights reserved.
Maize (Zea mays) is an important cereal crop worldwide. However, its yield and quality are adversely affected by salt stress resulting from soil hypersalinity. Exploring the regulatory mechanisms of stress responses is of vital importance to increase maize seed production. In the present study, we screened ethyl methanesulfonate-induced maize mutants and identified a salt-tolerant mutant. A single base was mutated in ZmWRKY20, leading to the formation of a truncated protein variant. A detailed phenotypic analysis revealed that this mutant had significantly higher resistance to wilting and lower reactive oxygen species levels than the inbred line B73. ZmWRKY20 showed transcriptional activity in yeast and specifically bound W-boxes according to the results of our yeast one-hybrid, electrophoretic mobility shift, and dual-luciferase assays. Overexpression of ZmWRKY20 decreased salt tolerance in maize. Transcriptome profiling revealed that ZmWRKY20 overexpression extensively reprogrammed genes involved in regulating defense and oxidation-reduction responses. The results substantiate that ZmWRKY20 is directly targeted to the basic leucine zipper (bZIP) motif in the transcription factor ZmbZIP111. It was also verified that ZmWRKY20 interacts with ZmWRKY115 and both proteins act jointly to enhance ZmbZIP111 repression. The results indicate that the ZmWRKY20 and ZmWRKY115 transcription factors interact in the nucleus, leading to repression of ZmbZIP111 expression by directly binding its promoter, and increase the sensitivity of maize seedlings to salt stress. The current study improves our understanding of the complicated responses of maize to salt stress.
The naturally occurring and mutated promoters inserted into expression plasmids or Escherichia coli chromosome are essential for recombinant protein production and metabolic engineering. Analyzing their activities and screening the promoter libraries require the simple and easy-to-use reporter. Here, we developed a novel and efficient approach to detect the promoter activity, based on E. coli cell growth inhibited by overexpression of bacteriophage ΦX174 gene E product (LyE), but recovered by pre-overexpression of Bacillus subtilis MraY (BsMraY). Under the conditional LyE construct expression in the absence or the presence of the BsMraY, activities of promoters including the reported PT7/lac, Ptac, PBAD, Prha, PhucR, PprpB, Pcum, the wild type and engineered Ptet for leaky and induced expression, the PthrC for auto-induction, and the Pms for constitutive expression were assayed. In one-plasmid coexpression system, the PBAD promoter activity detected using the reporter gene was related to the insertion site. The constructed LyE toxic effects were correlated with toxin expression levels, as determined by the split green fluorescent protein reconstitution. Microscopic analysis showed that cells lysis occurred by the LyE induced with arabinose. Taken together, the toxin reporter construct is a convenient and cost-effective tool to examine the promoter activity in E. coli.
Abstract Backgrounds Rapid separation methods with fusion of the affinity tags have been developed. However, the affinity tag for simply and cheaply separating the fused target protein is still lacking. Results Separation conditions for the human annexin A1 (hanA1) tagged emerald green fluorescent protein (EmGFP) in Escherichia coli cytoplasm were optimized via precipitation with CaCl2 and re-solubilization with EDTA-Na2. Combination of the affinity precipitation with each of three affinity purification approaches increased the hanA1-EmGFP purity, and on-resin cleavage facilitated release of tag-free EmGFP. With addition of Triton X-100 to the culture, the fused EmGFP, red fluorescent protein mCherry, or the FMN-dependent fluorescent protein LOV, was also prepared with increasing CaCl2concentrations after it was secreted to the culture from E. coli, whereas the hanA1-EmGFP fused to the amyQ signal sequence was insolubly produced in Bacillus subtilis cells, and the hanA1-EmGFP fused to the α signal peptide produced in Pichia pastoris was unable to be secreted to the culture. The affinity separation was visualized by use of three fluorescent proteins including the EmGFP, mCherry and LOV, and two colored proteins including a bacterial hemoglobin, and maize sirohydrochlorin ferrochelatase (mSF) showing brown containing the [2Fe–2S] cluster. The added EDTA-Na2disrupted the mSF structure, and inhibited activities of the selected four metal-dependent enzymes, but showed little impact on two specific proteases for cleaving the fusion proteins. After affinity precipitation, the tagged lysine decarboxylase was prepared as cross-linked enzyme aggregates. Conclusion The hanA1 tag is ideal for simple, rapid and cost-effective separation of the target proteins via intracellular and extracellular production in E. coli. This tag is also used for further affinity purification of the selected proteins and enzymes potentially applied in industry and diagnosis.
The basic leucine zipper (bZIP) is an important transcription factor required for fungal development, nutrient utilization, biosynthesis of secondary metabolites, and defense against various stresses. Aspergillus flavus is a major producer of aflatoxin and an opportunistic fungus on a wide range of hosts. However, little is known about the role of most bZIP genes in A. flavus. In this study, we developed a high-throughput gene knockout method based on an Agrobacterium-mediated transformation system. Gene knockout construction by yeast recombinational cloning and screening of the null mutants by double fluorescence provides an efficient way to construct gene-deleted mutants for this multinucleate fungus. We deleted 15 bZIP genes in A. flavus. Twelve of these genes were identified and characterized in this strain for the first time. The phenotypic analysis of these mutants showed that the 15 bZIP genes play a diverse role in mycelial growth (eight genes), conidiation (13 genes), aflatoxin biosynthesis (10 genes), oxidative stress response (11 genes), cell wall stress (five genes), osmotic stress (three genes), acid and alkali stress (four genes), and virulence to kernels (nine genes). Impressively, all 15 genes were involved in the development of sclerotia, and the respective deletion mutants of five of them did not produce sclerotia. Moreover, MetR was involved in this biological process. In addition, HapX and MetR play important roles in the adaptation to excessive iron and sulfur metabolism, respectively. These studies provide comprehensive insights into the role of bZIP transcription factors in this aflatoxigenic fungus of global significance.
Tobacco etch virus protease (TEVp) is a useful tool for removing fusion tags, but wild-type TEVp is less stable under oxidized redox state. In this work, we introduced and combined C19S, C110S and C130S into TEVp variants containing T17S, L56V, N68D, I77V and S135G to improve protein solubility, and S219V to inhibit self-proteolysis. The solubility and cleavage activity of the constructed variants in Escherichia coli strains including BL21(DE3), BL21(DE3)pLys, Rossetta(DE3) and Origami(DE3) under the same induction conditions were analyzed and compared. The desirable soluble amounts, activity, and oxidative stability were identified to be reluctantly favored in the TEVp. Unlike C19S, C110S and C130S hardly impacted on decreasing protein solubility in the BL21(DE3), but they contributed to improved tolerance to the oxidative redox state in vivo and in vitro. After two fusion proteins were cleaved by purified TEVp protein containing double mutations under the oxidized redox state, the refolded disulfide-rich bovine enterokinase catalytic domain or maize peroxidase with enhanced yields were released from the regenerated amorphous cellulose via affinity absorption of the cellulose-binding module as the affinity tag.
Tobacco etch virus protease (TEVp) is a powerful enzymatic reagent for removing fusion tag. In this work, we constructed nine TEVp variants with introducing one to three mutations of C19S, C110S and C130S into the soluble TEVp variant, TEVp 5M . Using the C-terminal green fluorescent protein (GFP) variant reporter, all constructs showed different solubility levels among four E. coli strains. The TEVp 5M containing the C110S and/or C130S mutations in the hyperoxic strain showed the enhanced the cleavage activity. Addition of dithiothreitol to the cultural medium increased the activity of certain constructs produced in the BL21(DE3), contrary to the added hydrogen peroxide, due to cytoplasmic redox change measured by the redox sensitive GFP construct. The more cysteine residues in the purified TEVp 5M were modified specifically than those in the other variants. All purified constructs showed similar specific activities in the presence of 5 mM dithiothreitol. In the buffer containing the compounds to aid disulfide bond formation of the refolded protein, the double mutant TEVp 5M C110S/C130S exhibited the highest cleavage efficiency. This variant was efficient for removing the fusion tag after refolding of cellulose-binding module tagged disulfide-rich proteins including bovine enteropeptidase and maize peroxidase absorbed on the regenerated amorphous cellulose.
Summary Maize leaf angle (LA) is a complex quantitative trait that is controlled by developmental signals, hormones, and environmental factors. However, the connection between histone methylation and LAs in maize remains unclear. Here, we reported that SET domain protein 128 ( SDG128 ) is involved in leaf inclination in maize. Knockdown of SDG128 using an RNA interference approach resulted in an expanded architecture, less large vascular bundles, more small vascular bundles, and larger spacing of large vascular bundles in the auricles. SDG128 interacts with ZmGID2 both in vitro and in vivo . Knockdown of ZmGID2 also showed a larger LA with less large vascular bundles and larger spacing of vascular bundles. In addition, the transcription level of cell wall expansion family genes ZmEXPA1 , ZmEXPB2 , and GRMZM2G005887 ; transcriptional factor genes Lg1 , ZmTAC1 , and ZmCLA4 ; and auxin pathway genes ZmYUCCA7 , ZmYUCCA8 , and Zm ARF22 was reduced in SDG128 and ZmGID2 knockdown plants. SDG128 directly targets ZmEXPA1 , ZmEXPB2 , LG1 , and ZmTAC1 and is required for H3K4me3 deposition at these genes. Together, the results of the present study suggest that SDG128 and ZmGID2 are involved in the maize leaf inclination.