Nadia Akter, Ummey Kulsum, Mohammad Moniruzzaman, Norito Yasuda, Kazuhito Akama
{"title":"Truncation of the calmodulin binding domain in rice glutamate decarboxylase 4 (OsGAD4) leads to accumulation of γ-aminobutyric acid and confers abiotic stress tolerance in rice seedlings","authors":"Nadia Akter, Ummey Kulsum, Mohammad Moniruzzaman, Norito Yasuda, Kazuhito Akama","doi":"10.1007/s11032-024-01460-1","DOIUrl":"https://doi.org/10.1007/s11032-024-01460-1","url":null,"abstract":"<p>GABA (Gamma-aminobutyric acid) is a non-protein amino acid widely known as major inhibitory neurotransmitter. It is synthesized from glutamate via the enzyme glutamate decarboxylase (GAD). GAD is ubiquitous in all organisms, but only plant GAD has ability to bind Ca<sup>2+</sup>/calmodulin (CaM). This kind of binding suppresses the auto-inhibition of Ca<sup>2+</sup>/calmodulin binding domain (CaMBD) when the active site of GAD is unfolded resulting in stimulated GAD activity. <i>OsGAD4</i> is one of the five <i>GAD</i> genes in rice genome. It was confirmed that <i>OsGAD4</i> has ability to bind to Ca<sup>2+</sup>/CaM. Moreover, it exhibits strongest expression against several stress conditions among the five <i>OsGAD</i> genes. In this study, CRISPR/Cas9-mediated genome editing was performed to trim the coding region of CaMBD from the <i>OsGAD4</i> gene, to remove its autoinhibitory function. DNA sequence analysis of the genome edited rice plants revealed the truncation of CaMBD (216 bp). Genome edited line (#14–1) produced 11.26 mg GABA/100 g grain, which is almost nine-fold in comparison to wild type. Short deletion in the coding region for CaMBD yielded in mutant (#14–6) with lower GABA content than wild type counterpart. Abiotic stresses like salinity, flooding and drought significantly enhanced GABA accumulation in #14–1 at various time points compared to wild-type and #14–6 under the same stress conditions. Moreover, upregulated mRNA expression in vegetative tissues seems correlated with the stress-responsiveness of <i>OsGAD4</i> when exposed to the above-mentioned stresses. Stress tolerance of <i>OsGAD4</i> genome edited lines was evidenced by the higher survival rate indicating the gene may induce tolerance against abiotic stresses in rice. This is the first report on abiotic stress tolerance in rice modulated by endogenous GABA.</p>","PeriodicalId":18769,"journal":{"name":"Molecular Breeding","volume":"46 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140008550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A tetraploid-dominated cytochimera developed from a natural bud mutant of the nonapomictic mandarin variety ‘Orah’","authors":"","doi":"10.1007/s11032-024-01456-x","DOIUrl":"https://doi.org/10.1007/s11032-024-01456-x","url":null,"abstract":"<h3>Abstract</h3> <p>Nonapomictic citrus tetraploids are desirable in citrus breeding for the production of triploid, seedless varieties, and polyploid rootstocks. However, only a few lines have been reported, and they were all generated using chemical methods. A 2x + 4 × cytochimera of the nonapomictic citrus variety ‘Orah’ mandarin, which developed from a bud mutant, was found due to its morphology differing from that of diploid plants and characterised via ploidy analysis combining flow cytometry and chromosome observation. The chimaera was stable, and there were 1.86–1.90 times as tetraploid cells as diploid cells. Anatomical structure observation revealed that the ‘Orah’ chimaera may be a periclinal chimaera with diploid cells in the L1 layer and tetraploid cells in the L2 and L3 layers. The chimaera showed some typical traits of polyploid plants, including thicker shoots, wider and thicker leaves, larger flowers and fruits, and fewer but larger seeds in fruits than in diploid plants. Almost all the seeds of the chimaera were monoembryonic. Most of the self-pollinated progenies of the chimaera were identified as tetraploids, and some triploid, pentaploid, and hexaploid plants were found. As a female, the chimaera produced allotriploids when crossed with Australian finger lime. In addition, 6 plants developed from polyembryonic seeds of the chimaera were identified as sexual tetraploid progenies with low-level recombinant genomes. Therefore, the ‘Orah’ 2x + 4 × chimaera can be used as a female parent to produce hybrid triploid and tetraploid citrus plants with high efficiency. Identification of the chimaera demonstrated that tetraploid citrus plants, especially nonapomictic varieties, can be generated from shoot bud mutants.</p>","PeriodicalId":18769,"journal":{"name":"Molecular Breeding","volume":"2015 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139949339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Accumulation of mutations in the AP2 homoeologs causes suppression of anther extrusion with altered spike and culm development in hexaploid wheat","authors":"Agetha Bigie Nanape, Takao Komatsuda, Katsuyuki Kakeda","doi":"10.1007/s11032-024-01458-9","DOIUrl":"https://doi.org/10.1007/s11032-024-01458-9","url":null,"abstract":"<p>Cleistogamy or closed flowering is a widely used trait in barley (<i>Hordeum vulgare</i>) breeding because it reduces the risk of fungal infection in florets at anthesis. Cleistogamy in barley is caused by a point mutation within the microRNA172 (miR172) target site of the <i>Cly1</i> gene, which encodes the Apetala2 (AP2) transcription factor. Because cleistogamy is not apparent in cultivars of hexaploid wheat (<i>Triticum aestivum</i>), a strategy to develop cleistogamous wheat was proposed by inducing point mutations in all three <i>AP2</i> homoeologs, which are the wheat orthologs of barley <i>Cly1</i>. In this study, we investigated the effects of miR172 target site mutations on wheat cleistogamy using double mutants by combining three previously obtained mutant alleles (<i>AP2-A1</i>, <i>D1</i> and <i>D2</i>) in a near-isogenic background. The <i>AP2-D2</i> allele had the greatest effect on reducing the anther extrusion rate and lodicule size compared with the other two mutant alleles. The double mutant containing the <i>AP2-A1</i> and <i>AP2-D2</i> alleles had a much greater suppression of anther extrusion by reducing the lodicule size than the single <i>AP2-D2</i> mutant, suggesting cumulative effects of the two mutant alleles. In addition, both single and double mutants exhibited compact spikes and shorter plant heights due to reduced rachis and culm internodes in the upper parts. The presence or absence of the wild-type <i>AP2-B</i> homoeolog had no significant effect on phenotype. This study provides insights into the cumulative effects of mutant <i>AP2</i> alleles in suppressing open flowering and provides a basis for further research on the development of complete cleistogamy in hexaploid wheat.</p>","PeriodicalId":18769,"journal":{"name":"Molecular Breeding","volume":"254 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139949230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"PbrCSP1, a pollen tube–specific cold shock domain protein, is essential for the growth and cold resistance of pear pollen tubes","authors":"","doi":"10.1007/s11032-024-01457-w","DOIUrl":"https://doi.org/10.1007/s11032-024-01457-w","url":null,"abstract":"<h3>Abstract</h3> <p>Cold shock domain proteins (CSPs), initially identified in <em>Escherichia coli</em>, have been demonstrated to play a positive role in cold resistance. Previous studies in wheat, rice, and <em>Arabidopsis</em> have indicated the functional conservation of CSPs in cold resistance between bacteria and higher plants. However, the biological functions of PbrCSPs in pear pollen tubes, which represent the fragile reproductive organs highly sensitive to low temperature, remain largely unknown. In this study, a total of 22 CSPs were identified in the seven Rosaceae species, with a focus on characterizing four PbrCSPs in pear (<em>Pyrus bretschneideri</em> Rehder). All four PbrCSPs were structurally conserved and responsive to the abiotic stresses, such as cold, high osmotic, and abscisic acid (ABA) treatments. PbrCSP1, which is specifically expressed in pear pollen tubes, was selected for further research. PbrCSP1 was localized in both the cytoplasm and nucleus. Suppressing the expression of <em>PbrCSP1</em> significantly inhibited the pollen tube growth in vitro. Conversely, overexpression of <em>PbrCSP1</em> promoted the growth of pear pollen tubes under the normal condition and, notably, under the cold environment at 4 °C. These findings highlight an essential role of PbrCSP1 in facilitating the normal growth and enhancing cold resistance in pear pollen tubes.</p>","PeriodicalId":18769,"journal":{"name":"Molecular Breeding","volume":"10 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139919706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Loss of function of OsL1 gene cause early flowering in rice under short-day conditions","authors":"","doi":"10.1007/s11032-024-01444-1","DOIUrl":"https://doi.org/10.1007/s11032-024-01444-1","url":null,"abstract":"<h3>Abstract </h3> <p>Heading date is one of the important agronomic traits that affects rice yield. In this study, we cloned a new rice B3 family gene, <em>OsL1</em>, which regulates rice heading date. Importantly, <em>osl1-1</em> and <em>osl1-2</em>, two different types of mutants of <em>OsL1</em> were created using the gene editing technology CRISPR/Cas9 system and exhibited 4 days earlier heading date than that of the wild type under short-day conditions. Subsequently, the plants overexpressing <em>OsL1</em>, OE-OsL1, showed a 2-day later heading date than the wild type in Changsha and a 5-day later heading date in Lingshui, but there was no significant difference in other yield traits. Moreover, the results of subcellular localization study indicated that OsL1 protein was located in the nucleus and the expression pattern analysis showed that <em>OsL1</em> gene was expressed in rice roots, stems, leaves, and panicles, and the expression level was higher at the root and weak green panicle. In addition, the <em>OsL1</em> gene was mainly expressed at night time under short-light conditions. The transcriptomic analysis indicated that <em>OsL1</em> might be involved in the <em>Hd1-Hd3a</em> pathway function. Together, our results revealed that the cloning and functional analysis of <em>OsL1</em> can provide new strategy for molecular design breeding of rice with suitable fertility period.</p>","PeriodicalId":18769,"journal":{"name":"Molecular Breeding","volume":"31 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139754321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bohong Su, Tianli Ge, Yuhang Zhang, Jianhao Wang, Fan Wang, Tu Feng, Baohui Liu, Fanjiang Kong, Zhihui Sun
{"title":"Genome-wide identification and expression analysis of the WNK kinase gene family in soybean","authors":"Bohong Su, Tianli Ge, Yuhang Zhang, Jianhao Wang, Fan Wang, Tu Feng, Baohui Liu, Fanjiang Kong, Zhihui Sun","doi":"10.1007/s11032-024-01440-5","DOIUrl":"https://doi.org/10.1007/s11032-024-01440-5","url":null,"abstract":"<p>WNK kinases are a unique class of serine/threonine protein kinases that lack a conserved catalytic lysine residue in the kinase domain, hence the name WNK (with no K, i.e., lysine). WNK kinases are involved in various physiological processes in plants, such as circadian rhythm, flowering time, and stress responses. In this study, we identified 26 <i>WNK</i> genes in soybean and analyzed their phylogenetic relationships, gene structures, chromosomal distribution, <i>cis</i>-regulatory elements, expression patterns, and conserved protein motifs. The soybean <i>WNK</i> genes were unevenly distributed on 15 chromosomes and underwent 21 segmental duplication events during evolution. We detected 14 types of <i>cis</i>-regulatory elements in the promoters of the <i>WNK</i> genes, indicating their potential involvement in different signaling pathways. The transcriptome database revealed tissue-specific and salt stress-responsive expression of <i>WNK</i> genes in soybean, the second of which was confirmed by salt treatments and qRT-PCR analysis. We found that most <i>WNK</i> genes were significantly up-regulated by salt stress within 3 h in both roots and leaves, except for <i>WNK5</i>, which showed a distinct expression pattern. Our findings provide valuable insights into the molecular characteristics and evolutionary history of the soybean <i>WNK</i> gene family and lay a foundation for further analysis of <i>WNK</i> gene functions in soybean.</p>","PeriodicalId":18769,"journal":{"name":"Molecular Breeding","volume":"54 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139754386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A novel variation of <i>TaGW2-6B</i> increases grain weight without penalty in grain protein content in wheat (<i>Triticum aestivum</i> L.).","authors":"Chan Bi, Chaoxiong Wei, Jinghui Li, Shaozhe Wen, Huanhuan Zhao, Jiazheng Yu, Xintian Shi, Yuan Zhang, Qiaofeng Liu, Yufeng Zhang, Baoyun Li, Mingshan You","doi":"10.1007/s11032-024-01455-y","DOIUrl":"10.1007/s11032-024-01455-y","url":null,"abstract":"<p><p>Yield and quality are two crucial breeding objects of wheat therein grain weight and grain protein content (GPC) are two key relevant factors correspondingly. Investigations of their genetic mechanisms represent special significance for breeding. In this study, 199 F<sub>2</sub> plants and corresponding F<sub>2:3</sub> families derived from Nongda3753 (ND3753) and its EMS-generated mutant 564 (M564) were used to investigate the genetic basis of larger grain and higher GPC of M564. QTL analysis identified a total of 33 environmentally stable QTLs related to thousand grain weight (TGW), grain area (GA), grain circle (GC), grain length (GL), grain width (GW), and GPC on chromosomes 1B, 2A, 2B, 4D, 6B, and 7D, respectively, among which <i>QGw.cau-6B.1</i>, <i>QTgw.cau-6B.1</i>, <i>QGa.cau-6B.1</i>, and <i>QGc.cau-6B.1</i> shared overlap confidence interval on chromosome 6B. This interval contained the <i>TaGW2</i> gene playing the same role as the QTLs, so <i>TaGW2-6B</i> was cloned and sequenced. Sequence alignment revealed two G/A SNPs between two parents, among which the SNP in the seventh exon led to a premature termination in M564. A KASP marker was developed based on the SNP, and single-marker analysis on biparental populations showed that the mutant allele could significantly increase GW and TGW, but had no effect on GPC. Distribution detection of the mutant allele through KASP marker genotyping and sequence alignment against databases ascertained that no materials harbored this allele within natural populations. This allele was subsequently introduced into three different varieties through molecular marker-assisted backcrossing, and it was revealed that the allele had a significant effect on simultaneously increasing GW, TGW, and even GPC in all of three backgrounds. Summing up the above, it could be concluded that a novel elite allele of <i>TaGW2-6B</i> was artificially created and might play an important role in wheat breeding for high yield and quality.</p><p><strong>Supplementary information: </strong>The online version contains supplementary material available at 10.1007/s11032-024-01455-y.</p>","PeriodicalId":18769,"journal":{"name":"Molecular Breeding","volume":"44 2","pages":"15"},"PeriodicalIF":2.6,"publicationDate":"2024-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10864231/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139741442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Molecular BreedingPub Date : 2024-02-08eCollection Date: 2024-02-01DOI: 10.1007/s11032-024-01454-z
Chengxiu Wu, Jingyun Luo, Yingjie Xiao
{"title":"Multi-omics assists genomic prediction of maize yield with machine learning approaches.","authors":"Chengxiu Wu, Jingyun Luo, Yingjie Xiao","doi":"10.1007/s11032-024-01454-z","DOIUrl":"10.1007/s11032-024-01454-z","url":null,"abstract":"<p><p>With the improvement of high-throughput technologies in recent years, large multi-dimensional plant omics data have been produced, and big-data-driven yield prediction research has received increasing attention. Machine learning offers promising computational and analytical solutions to interpret the biological meaning of large amounts of data in crops. In this study, we utilized multi-omics datasets from 156 maize recombinant inbred lines, containing 2496 single nucleotide polymorphisms (SNPs), 46 image traits (i-traits) from 16 developmental stages obtained through an automatic phenotyping platform, and 133 primary metabolites. Based on benchmark tests with different types of prediction models, some machine learning methods, such as Partial Least Squares (PLS), Random Forest (RF), and Gaussian process with Radial basis function kernel (GaussprRadial), achieved better prediction for maize yield, albeit slight difference for method preferences among i-traits, genomic, and metabolic data. We found that better yield prediction may be caused by various capabilities in ranking and filtering data features, which is found to be linked with biological meaning such as photosynthesis-related or kernel development-related regulations. Finally, by integrating multiple omics data with the RF machine learning approach, we can further improve the prediction accuracy of grain yield from 0.32 to 0.43. Our research provides new ideas for the application of plant omics data and artificial intelligence approaches to facilitate crop genetic improvements.</p><p><strong>Supplementary information: </strong>The online version contains supplementary material available at 10.1007/s11032-024-01454-z.</p>","PeriodicalId":18769,"journal":{"name":"Molecular Breeding","volume":"44 2","pages":"14"},"PeriodicalIF":2.6,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10853138/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139723404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cam Chau Nguyen, Tien Van Vu, Rahul Mahadev Shelake, Nhan Thi Nguyen, Tran Dang Khanh, Woe-Yeon Kim, Jae-Yean Kim
{"title":"Generation of parthenocarpic tomato plants in multiple elite cultivars using the CRISPR/Cas9 system","authors":"Cam Chau Nguyen, Tien Van Vu, Rahul Mahadev Shelake, Nhan Thi Nguyen, Tran Dang Khanh, Woe-Yeon Kim, Jae-Yean Kim","doi":"10.1007/s11032-024-01452-1","DOIUrl":"https://doi.org/10.1007/s11032-024-01452-1","url":null,"abstract":"<p>Tomato (<i>Solanum lycopersicum</i> L.) is one of the most important crops in the world for its fruit production. Advances in cutting-edge techniques have enabled the development of numerous critical traits related to the quality and quantity of tomatoes. Genetic engineering techniques, such as gene transformation and gene editing, have emerged as powerful tools for generating new plant varieties with superior traits. In this study, we induced parthenocarpic traits in a population of elite tomato (ET) lines. At first, the adaptability of ET lines to genetic transformation was evaluated to identify the best-performing lines by transforming the <i>SlANT1</i> gene overexpression cassette and then later used to produce the <i>SlIAA9</i> knockout lines using the CRISPR/Cas9 system. ET5 and ET8 emerged as excellent materials for these techniques and showed higher efficiency. Typical phenotypes of knockout <i>sliaa9</i> were clearly visible in G0 and G1 plants, in which simple leaves and parthenocarpic fruits were observed. The high efficiency of the CRISPR/Cas9 system in developing new tomato varieties with desired traits in a short period was demonstrated by generating T-DNA-free homozygous <i>sliaa9</i> knockout plants in the G1 generation. Additionally, a simple artificial fertilization method was successfully applied to recover seed production from parthenocarpic plants, securing the use of these varieties as breeding materials.</p>","PeriodicalId":18769,"journal":{"name":"Molecular Breeding","volume":"104 ( Pt 2) 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139663047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Strigolactone and abscisic acid synthesis and signaling pathways are enhanced in the wheat oligo-tillering mutant ot1","authors":"Jiaxing Bai, Huijun Guo, Hongchun Xiong, Yongdun Xie, Jiayu Gu, Linshu Zhao, Shirong Zhao, Yuping Ding, Luxiang Liu","doi":"10.1007/s11032-024-01450-3","DOIUrl":"https://doi.org/10.1007/s11032-024-01450-3","url":null,"abstract":"<p>Tiller number greatly contributes to grain yield in wheat. Using ethylmethanesulfonate mutagenesis, we previously discovered the oligo-tillering mutant <i>ot1</i>. The tiller number was significantly lower in <i>ot1</i> than in the corresponding wild type from the early tillering stage until the heading stage. Compared to the wild type, the thousand-grain weight and grain length were increased by 15.41% and 31.44%, respectively, whereas the plant height and spike length were decreased by 26.13% and 37.25%, respectively. Transcriptomic analysis was conducted at the regreening and jointing stages to identify differential expressed genes (DEGs). Functional enrichment analysis with the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) databases showed differential expression of genes associated with ADP binding, transmembrane transport, and transcriptional regulation during tiller development. Differences in tiller number in <i>ot1</i> led to the upregulation of genes in the strigolactone (SL) and abscisic acid (ABA) pathways. Specifically, the SL biosynthesis genes <i>DWARF</i> (<i>D27</i>), <i>D17</i>, <i>D10</i>, and <i>MORE AXILLARY GROWTH 1</i> (<i>MAX1</i>) were upregulated by 3.37- to 8.23-fold; the SL signal transduction genes <i>D14</i> and <i>D53</i> were upregulated by 1.81- and 1.32-fold, respectively; the ABA biosynthesis genes <i>9</i>-<i>CIS</i>-<i>EPOXICAROTENOID DIOXIGENASE 3</i> (<i>NCED3</i>) and <i>NCED5</i> were upregulated by 1.66- and 3.4-fold, respectively; and <i>SNF1-REGULATED PROTEIN KINASE2</i> (<i>SnRK2</i>) and <i>PROTEIN PHOSPHATASE 2C</i> (<i>PP2C</i>) genes were upregulated by 1.30- to 4.79-fold. This suggested that the tiller number reduction in <i>ot1</i> was due to alterations in plant hormone pathways. Genes known to promote tillering growth were upregulated, whereas those known to inhibit tillering growth were downregulated. For example, <i>PIN-FORMED 9</i> (<i>PIN9</i>), which promotes tiller development, was upregulated by 8.23-fold in <i>ot1</i>; <i>Ideal Plant Architecture 1</i> (<i>IPA1</i>), which inhibits tiller development, was downregulated by 1.74-fold. There were no significant differences in the expression levels of <i>TILLER NUMBER 1</i> (<i>TN1</i>) or <i>TEOSINTE BRANCHED 1</i> (<i>TB1</i>), indicating that the tiller reduction in <i>ot1</i> was not controlled by known genes. Our findings provide valuable data for subsequent research into the genetic bases and regulatory mechanisms of wheat tillering.</p>","PeriodicalId":18769,"journal":{"name":"Molecular Breeding","volume":"69 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139663050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}