In recent years, the spread of clubroot disease caused by Plasmodiophora brassicae infection has seriously affected the yield and quality of Brassica juncea (L.) Czern.. The cascade of mitogen-activated protein kinases (MAPKs), a highly conserved signaling pathway, plays an important role in plant responses to both biotic and abiotic stress conditions. To mine the MAPK genes related to clubroot disease resistance in B. juncea, we conducted a genome-wide analysis on this vegetable, and we analyzed the phylogenetic evolution and gene structure of the MAPK gene family in mustard. The 66 BjuMAPK genes identified by screening the whole genome sequence of B. juncea were unevenly distributed on 17 chromosomes. At the genomic scale, tandem repeats led to an increase in the number of MAPK genes in B. juncea. It was found that members of the same subfamily had similar gene structures, and there were great differences among different subfamilies. These predicted cis-acting elements were related to plant hormones, stress resistance, and plant growth and development. The expression of BjuMAPK02, BjuMAPK15, BjuMAPK17, and BjuMAPK19 were down-regulated or up-regulated in response to P. brassicae infection. The above results lay a theoretical foundation for further studying the functions of BjuMAPK genes in B. juncea in response to the biotic stress caused by clubroot disease.
Mustard Plant/parasitology* ; Plasmodiophorida/pathogenicity* ; Plant Diseases/genetics* ; Mitogen-Activated Protein Kinases/metabolism* ; Phylogeny ; Disease Resistance/genetics* ; Gene Expression Regulation, Plant ; Genome, Plant ; Plant Proteins/genetics*

Laccases (LACs), belonging to the multicopper oxidase family, are closely associated with various biological functions including lignin synthesis and responses to biotic and abiotic stresses in plants. However, few studies have reported the laccase genes in China rose (Rosa chinensis). Prickles cause difficulties to the management and harvest of R. chinensis and have become a trait concerned in the breeding. To investigate the expression patterns of laccase genes in roses, we cloned a laccase gene from an ancient variety R. chinensis 'Old Blush' and named it RcLAC15. The expression level of RcLAC15 in prickles was significantly higher than those in roots, stems, and leaves. Fifty-eight laccase genes were identified in the genome of R. chinensis, and bioinformatics analysis revealed that RcLAC15 was a homolog of AtLAC15, predicting that RcLAC15 was a stable hydrophilic protein without transmembrane structures. The recombinant expression vector pBI121-proRcLAC15:: GUS was introduced into Arabidopsis, and GUS staining results showed that the RcLAC15 promoter specifically drove GUS gene expression at the edges of Arabidopsis leaves. In summary, RcLAC15 is a gene specifically expressed in the prickles of R. chinensis. This discovery provides a reference for exploring the biological functions of laccase genes in the prickles of R. chinensis.
Laccase/metabolism* ; Rosa/enzymology* ; Cloning, Molecular ; Gene Expression Regulation, Plant ; Plant Proteins/metabolism* ; Arabidopsis/metabolism* ; Plants, Genetically Modified/metabolism*

Sucrose non-fermenting 1-related protein kinase 1 (SnRK1) is one of the highly conserved Ca²⁺ non-dependent serine/threonine protein kinases, playing a crucial role in regulating the stress responses, growth, and development of plants. SnRK1 is a three-subunit complex, and it is involved in responding to the signaling transduction induced by low-energy/low-sugar conditions. SnRK1 responds biotic and abiotic stress conditions (such as salt, drought, low/high temperatures, and diseases) through phosphorylation of key metabolic enzymes and regulatory proteins, regulation of transcription, and interactions with other proteins. Furthermore, SnRK1 is not only involved in hormone signaling pathways mediated by abscisic acid (ABA), jasmonic acid (JA) and salicylic acid (SA), but also regulates plant autophagy by inhibiting the activity of target of rapamycin (TOR). In this review, we summarized the current results of research on the discovery, structure, and classification of plant SnRK1 and its roles in the stress responses, growth, and development of plants. Furthermore, this article proposes the directions of future research. This review provides good genetic resources and a theoretical basis for the genetic improvement and biological breeding for enhancing the stress tolerance of crops.
Stress, Physiological/physiology* ; Protein Serine-Threonine Kinases/metabolism* ; Plant Development/genetics* ; Signal Transduction ; Gene Expression Regulation, Plant ; Plant Proteins/physiology* ; Plants/metabolism* ; Arabidopsis Proteins/physiology* ; Plant Growth Regulators/metabolism*

The plant F-box protein more axillary growth 2 (MAX2) is a key factor in the signal transduction of strigolactones (SLs) and karrinkins (KARs). As the main component of the SKP1-CUL1-FBX (SCF) complex ubiquitin ligase E3, MAX2 is responsible for specifically recognizing the target proteins, suppressor of MAX2 1/SMAX1-like proteins (SMAX1/SMXLs), which would be degraded after ubiquitination. It can thereby regulate plant morphogenesis and stress responses. There exist homologous genes of MAX2 in the important grain and oil crop soybean (Glycine max). However, its role in plant defense responses has not been investigated yet. Here, GmMAX2b, a homologous gene of MAX2, was successfully cloned from stressed soybean. Bioinformatics analysis revealed that there were two MAX2 homologous genes, GmMAX2a and GmMAX2b, with a similarity of 96.2% in soybean. Their F-box regions were highly conserved. The sequence alignment and cluster analysis of plant MAX2 homologous proteins basically reflected the evolutionary relationship of plants and also suggested that soybean MAX2 might be a multifunctional protein. Expression analysis showed that plant pathogen infection and salicylic acid treatment induced the expression of GmMAX2b in soybean, which is consistent with that of MAX2 in Arabidopsis. Ectopic expression of GmMAX2b compensated for the susceptibility of Arabidopsis max2-2 mutant to pathogen, indicating that GmMAX2b positively regulated plant disease resistance. In addition, yeast two hybrid technology was used to explore the potential target proteins of GmMAX2b. The results showed that GmMAX2b interacted with SMXL6 and weakly interacted with SMXL2. In summary, GmMAX2b is a positive regulator in plant defense responses, and its expression is induced by pathogen infection and salicylic acid treatment. GmMAX2b might exert its effect through interaction with SMXL6 and SMXL2. This study expands the theoretical exploration of soybean disease resistant F-box and provides a scientific basis for future soybean disease resistant breeding.
Glycine max/metabolism* ; Disease Resistance/genetics* ; Plant Diseases/immunology* ; Plant Proteins/genetics* ; Cloning, Molecular ; Gene Expression Regulation, Plant ; F-Box Proteins/genetics* ; Arabidopsis/genetics* ; Phylogeny

Flowering and bolting are important agronomic traits in cruciferous crops such as Brassica juncea. Timely flowering can ensure the crop organ yield and quality, as well as seed propagation. The WRKY family plays an important role in regulating plant bolting and flowering, while the function and mechanism of WRKY12 in B. juncea remain unknown. To explore its function and mechanism in bolting and flowering of B. juncea, we cloned and characterized the BjuWRKY12 gene in B. juncea and found that its expression levels were significantly higher in flowers and inflorescences than in leaves. BjuWRKY12 belonged to the Ⅱc subfamily of the WRKY family, and subcellular localization indicated that the protein was located in the nucleus. Ectopic overexpression of BjuWRKY12 in transgenic lines promoted bolting and flowering, leading to significant increases in the expression levels of flowering integrators SOC1 and FUL. Furthermore, yeast one-hybrid and dual luciferase reporter system assays confirmed that BjuWRKY12 directly bound to the promoters of BjuSOC1 and BjuFUL, undergoing protein-DNA interactions. This discovery gives new insights into the regulation network and molecular mechanisms of BjuWRKY12, laying a theoretical foundation for the breeding of high-yield and high-quality varieties of B. juncea.
Mustard Plant/metabolism* ; Flowers/growth & development* ; Plant Proteins/physiology* ; Promoter Regions, Genetic/genetics* ; Gene Expression Regulation, Plant ; Plants, Genetically Modified/genetics* ; Transcription Factors/metabolism* ; MADS Domain Proteins/metabolism*

Stresses induced by the deficiency or excess of trace mineral elements, such as manganese (Mn), represent a common limiting factor for the production of crops like Brassica napus. To identify key genes involved in Mn allocation in B. napus and elucidate the underlying mechanisms, a member of the metal tolerance protein (MTP) family obtained in the previous screening of cDNA library of B. napus under Mn stress was selected as the research subject. Based on the sequence information and phylogenetic analysis, it was named as BnMTP10. It belongs to the Mn-cation diffusion facilitator (CDF) subfamily. Expression of BnMTP10 in yeast significantly improved the tolerance of transformants to excessive Mn and iron (Fe) and reduced the accumulation of Mn and Fe. However, the yeast transformants exhibited no significant changes in tolerance to excess cadmium, boron, aluminum, zinc, or copper. The qRT-PCR results demonstrated that the flowers of B. napus had the highest expression of BnMTP10, followed by roots and leaves. Subcellular localization studies revealed that BnMTP10 was localized in the endoplasmic reticulum (ER). Compared with wild-type plants, transgenic Arabidopsis overexpressing BnMTP10 exhibited enhanced tolerance to excessive Mn stress but showed no significant difference under Fe stress. Correspondingly, under excessive Mn stress, the Mn content in the roots of transgenic Arabidopsis increased significantly. However, under excessive Fe stress, the Fe content in transgenic Arabidopsis did not alter significantly. According to the results, we hypothesize that BnMTP10 may alleviate excessive Mn stress in plants by mediating Mn transport to the ER. This study facilitated our understanding of efficient mineral nutrients, and provided theoretical foundations and gene resources for breeding B. napus.
Brassica napus/genetics* ; Manganese/metabolism* ; Plants, Genetically Modified/genetics* ; Plant Proteins/physiology* ; Arabidopsis/metabolism* ; Gene Expression Regulation, Plant ; Phylogeny ; Cation Transport Proteins/metabolism* ; Stress, Physiological

Improving the nitrogen use efficiency (NUE) of Brassica napus is of significant importance for achieving the national goal of zero growth in chemical fertilizer application and ensuring the green development of the rapeseed industry. This study aims to explore the effects of the nitrate transporter gene BnaNRT1.5s on the nitrogen transport and NUE of B. napus, providing excellent genetic resources for the development of nitrogen-efficient B. napus varieties. The spatiotemporal expression of BnaA05.NRT1.5 as a key nitrogen responsive gene was profiled by qRT-PCR at different growth stages and for different tissue samples of B. napus 'Westar'. Subcellular localization was employed to examine its expression pattern in the cells. Additionally, CRISPR/Cas9 was used to create BnaNRT1.5s knockout lines, which were subjected to hydroponic experiments under high nitrogen (12.0 mmol/L) and low nitrogen (0.3 mmol/L) conditions. After the seedlings were cultivated for 21 days, root and shoot samples were collected for weighing, nitrogen content determination, xylem sap nitrate content assessment, and calculation of total nitrogen and NUE. The B. napus nitrate transporter BnaA05.NRT1.5 was localized to the cell membrane. During the seedling and early bolting stages, BnaA05.NRT1.5 was predominantly expressed in roots, while it was highly expressed in old leaves and mature silique skin during the reproductive stage. Compared with the wild type, the mutant BnaNRT1.5s showed significant increases in the dry weight and total nitrogen of seedlings under both high and low nitrogen conditions. Under low nitrogen conditions, NUE in the roots of BnaNRT1.5s significantly improved. Notably, under both high and low nitrogen conditions, the nitrate content in the shoots of BnaNRT1.5s decreased significantly, while that in the roots increased significantly, resulting in a significantly decreased shoot-to-root nitrate content ratio. BnaNRT1.5s is involved in regulating the transport of nitrate from the roots to the shoots, and its mutation enhances nitrogen absorption and utilization in B. napus seedlings, promoting seedling growth. This study not only provides references for understanding the physiological and molecular mechanisms by which BnaNRT1.5s regulates NUE but also offers valuable genetic resources for improving NUE in B. napus.
Brassica napus/genetics* ; Anion Transport Proteins/metabolism* ; Nitrogen/metabolism* ; Nitrate Transporters ; Plant Proteins/metabolism* ; Nitrates/metabolism* ; Gene Expression Regulation, Plant ; Biological Transport

Geminiviruses cause substantial crop yield losses worldwide. The replication initiator protein (Rep) encoded by geminiviruses is indispensable for geminiviral replication. The Rep protein encoded by beet severe curly top virus (BSCTV, genus Curtovirus, family Geminiviridae) induces VARIANT IN METHYLATION 5 (VIM5) expression in Arabidopsis leaves upon BSCTV infection. VIM5 functions as a ubiquitination-related E3 ligase to promote the proteasomal degradation of methyltransferases, resulting in reduction of methylation levels in the BSCTV C2-3 promoter. However, the specific domains of Rep responsible for VIM5 induction remain poorly characterized. Although Rep proteins from several geminiviruses act as viral suppressors of RNA silencing (VSRs), whether BSCTV Rep also possesses VSR activity remains to be illustrated. In this study, we employed a transient expression system in the 16c-GFP transgenic and the wild-type Nicotiana benthamiana plants to analyze the VSR and the VIM5-inducing activities of different truncated Rep proteins haboring distinct domains. We found that the N-terminal domain (amino acids 1-180) of Rep suppressed GFP silencing in 16c-GFP transgenic N. benthamiana leaves. The minimal N-terminal fragment (amino acids 1-104) induced VIM5 expression upon co-infiltration, while C-terminal truncations lacked VIM5-inducing activity. Our results indicate that the N-terminal domain of Rep encoded by BSCTV mediates the suppression of RNA silencing and induces VIM5 expression. Thus, our findings contribute to a better understanding of interactions between geminiviral Rep and plant hosts.
Geminiviridae/genetics* ; Nicotiana/metabolism* ; Arabidopsis/metabolism* ; RNA Interference ; Viral Proteins/metabolism* ; Arabidopsis Proteins/metabolism* ; Plants, Genetically Modified/metabolism* ; Protein Domains ; Plant Diseases/virology* ; Methyltransferases/metabolism* ; Ubiquitin-Protein Ligases/metabolism* ; DNA Helicases/genetics*

YABBY proteins are important transcription factors that regulate morphogenesis and organ development in plants. In order to study the YABBY of strawberry, bioinformatic technique were used to identify the YABBY gene families in Fragaria vesca (diploid) and Fragaria×ananassa (octoploid), and then analyze the sequence characters, phylogeny and collinearity of the family members. The RNA-seq data and the quantitative reverse transcription-polymerase chain reaction (qRT-PCR) technique were used to assay the expression patterns of the family members. A green fluorescent protein (GFP) was fused with FvYABBYs and transiently expressed in tobacco leaf cells for the subcellular localization. As the results, six FvYABBY genes and 26 FxaYABBY genes were identified from F. vesca and F.×ananassa, respectively. The FvYABBY genes were grouped into five clades, and five family members were orthologous with AtYABBY genes of Arabidopsis. In F. vesca, all of the FvYABBYs were basically not expressed not expressed in root and receptacle, while FvYABBY1, FvYABBY2, FvYABBY5 and FvYABBY6 were highly expressed in leaf, shoot, flower and achene. In F.×ananassa, FxaYABBY1, FxaYABBY2, FxaYABBY5 and FxaYABBY6 were expressed in achene, and all FxaYABBY were poorly or not expressed in receptacle. Additionally, under the abiotic stresses of low temperature, high salt and drought, the expression of FvYABBY1, FvYABBY3, FvYABBY4 and FvYABBY6 were down-regulated, FvYABBY5 was up-regulated, and FvYABBY2 was up-regulated and then down-regulated. In tobacco leaf cells, the subcellular localization of FvYABBY proteins were in the nucleus. These results provides a foundation for the functional researches of YABBY gene in strawberry.
Fragaria/genetics* ; Arabidopsis ; Biological Assay ; Cold Temperature ; Computational Biology

TCP family as plant specific transcription factor, plays an important role in different aspects of plant development. In order to screen TCP family members in tobacco, the homologous sequences of tobacco and Arabidopsis TCP family were identified by genome-wide homologous alignment. The physicochemical properties, phylogenetic relationships and cis-acting elements were analyzed by bioinformatics. The homologous genes of AtTCP3/AtTCP4 were screened, and RT-qPCR was used to detect the changes of gene expression upon 20% PEG6000 treatment. The results show that tobacco contains 63 TCP family members. Their amino acid sequence length ranged from 89 aa to 596 aa, and their protein hydropathicity grand average of hydropathicity (GRAVY) ranged from -1.147 to 0.125. The isoelectric point (pI) ranges from 4.42 to 9.94, the number of introns is 0 to 3, and the subcellular location is all located in the nucleus. The results of conserved domain and phylogenetic relationship analysis showed that the tobacco TCP family can be divided into PCF, CIN and CYC/TB1 subfamilies, and each subfamily has a stable sequence. The results of cis-acting elements in gene promoter region showed that TCP family genes contain low docile acting elements (LTR) and a variety of stress and metabolic regulation related elements (MYB, MYC). Analysis of gene expression patterns showed that AtTCP3/AtTCP4 homologous genes (NtTCP6, NtTCP28, NtTCP30, NtTCP33, NtTCP42, NtTCP57, NtTCP63) accounted for 20% PEG6000 treatment significantly up-regulated/down-regulated expression, and NtTCP30 and NtTCP57 genes were selected as candidate genes in response to drought. The results of this study analyzed the TCP family in the tobacco genome and provided candidate genes for the study of drought-resistance gene function and variety breeding in tobacco.
Nicotiana/genetics* ; Phylogeny ; Plant Breeding ; Amino Acid Sequence ; Arabidopsis ; Polyethylene Glycols