Eggplant is an important horticultural crop and one of the most widely grown vegetables in the Solanaceae family. Eggplant fruit-related agronomic traits are complex quantitative traits with low efficiency and long cycle time for traditional breeding selection. With the rapid development of high-throughput sequencing technology and bioinformatics tools, genome-wide association study (GWAS) has shown great application potential in analyzing the genetic rules of complex agronomic traits related to eggplant fruits. This paper first reviews the progress of genome-wide association analysis in eggplant fruit shape, fruit color and other fruit-related agronomic traits. Subsequently, aiming at the problem of missing heritability, which is common in the genetic studies of eggplant quantitative traits, this paper puts forward the development strategies of eggplant GWAS in the future based on the hot spots of application of four GWAS strategies in the research of agronomics traits related to eggplant fruits. Lastly, the application of GWAS strategy in the field of eggplant molecular breeding is expected to provide a theoretical basis and reference for the future use of GWAS to analyze the genetic basis of various eggplant fruit-related traits and to select fruit materials that meet consumer needs.
Solanum melongena/genetics* ; Fruit/genetics* ; Genome-Wide Association Study ; Plant Breeding ; Agriculture ; Vegetables

In this study, the chloroplast genome of Camellia insularis Orel & Curry was sequenced using high-throughput sequencing technology. The results showed that the chloroplast genome of C. insularis was 156 882 bp in length with a typical tetrad structure, encoding 132 genes, including 88 protein-coding genes, 36 tRNA genes, and 8 rRNA genes. Codon preference analysis revealed that the highest number of codons coded for leucine, with a high A/U preference in the third codon position. Additionally, 67 simple sequence repeats (SSR) loci were identified, with a preference for A and T bases. The inverted repeat (IR) boundary regions of the chloroplast genome of C. insularis were relatively conserved, except for a few variable regions. Phylogenetic analysis indicated that C. insularis was most closely related to C. fascicularis. Yellow camellia is a valuable material for genetic engineering breeding. This study provides fundamental genetic information on chloroplast engineering and offers valuable resources for conducting in-depth research on the evolution, species identification, and genomic breeding of yellow Camellia.
Genome, Chloroplast/genetics* ; Phylogeny ; Plant Breeding ; Camellia/genetics* ; Chloroplasts/genetics*

Auto-inhibited Ca²⁺-ATPase (ACA) is one of the Ca²⁺-ATPase subfamilies that plays an important role in maintaining Ca²⁺ concentration balance in plant cells. To explore the function and gene expression pattern of the RcACA gene family in castor, bioinformatics analysis was used to identify the members of the RcACA gene family in castor. The basic physical and chemical properties, subcellular location, protein secondary and tertiary structure, conserved domain, conserved motif, gene structure, chromosome location and collinear relationship, as well as the evolutionary characteristics and promoter cis-acting elements were predicted and analyzed. The expression pattern of the RcACA gene under abiotic stress was analyzed by expression (fragments per kilobase of exon model per million mapped fragments, FPKM) in castor transcriptome data. The results showed that 8 RcACA gene family members were identified in castor, acidic proteins located in the plasma membrane. In the secondary structure of all proteins, the α-helix and random coil is more; the RcACA genes were clustered into three categories, and the design of the genes in the same category was similar to the conserved motif. Both of them had four typical domains, RcACA3-RcACA8 had a Ca²⁺-ATPase N-terminal autoinhibitory domain. The RcACA gene is mostly located on the long arm of the chromosome and has 2 pairs of collinear relationships. There are more light response elements but fewer hormone-induced elements located upstream of the RcACA coding region. Interspecific clustering showed that the evolution of ACA genes among species was conservative. Tissue expression pattern analysis showed that RcACA genes showed apparent tissue expression specificity, and most of the genes showed the highest expression level in male flowers. Expression analysis under abiotic stress showed that RcACA2-RcACA8 were up-regulated under high salt and drought stress, and RcACA1 was up-regulated at 0-24 h under low-temperature stress, indicating that RcACA genes positively responded to abiotic stresses. The above results provide a theoretical basis for exploring the role of the RcACA gene in castor growth, development and stress response.
Genome, Plant ; Stress, Physiological/genetics* ; Transcriptome ; Promoter Regions, Genetic ; Phylogeny ; Plant Proteins/metabolism* ; Gene Expression Regulation, Plant

Dracaena marginata is a widely cultivated horticultural plant in the world, which has high ornamental and medicinal value. In this study, the whole genome of leaves from D. marginata was sequenced by Illumina HiSeq 4000 platform. The chloroplast genome were assembled for functional annotation, sequence characteristics and phylogenetic analysis. The results showed that the chloroplast genome of D. marginata composed of four regions with a size of 154 926 bp, which was the smallest chloroplast genome reported for Dracaena species to date. A total of 132 genes were identified, including 86 coding genes, 38 tRNA genes and 8 rRNA genes. Codon bias analysis found that the codon usage bias was weak and there was a bias for using A/U base endings. 46 simple sequence repeat and 54 repeats loci were detected in the chloroplast genome, with the maximum detection rate in the large single copy region and inverted repeat region, respectively. The inverted repeats boundaries of D. marginata and Dracaena were highly conserved, whereas gene location differences occurred. Phylogenetic analysis revealed that D. serrulata and D. cinnabari form a monophyletic clade, which was the closest relationship and conformed to the morphological classification characteristics. The analysis of the chloroplast genome of D. marginata provides important data basis for species identification, genetic diversity and chloroplast genome engineering of Dracaena.
Phylogeny ; Dracaena ; Genome, Chloroplast/genetics* ; Base Sequence ; Genes, Plant

Na⁺/H⁺ antiporter (NHX) gene subfamily plays an important role in plant response to salt stress. In this study, we identified the NHX gene family members of Chinese cabbage and analyzed the expression patterns of BrNHXs gene in response to abiotic stresses such as high temperature, low temperature, drought and salt stress. The results showed that there were 9 members of the NHX gene family in Chinese cabbage, which were distributed on 6 chromosomes respectively. The number of amino acids was 513-1 154 aa, the relative molecular weight was 56 804.22-127 856.66 kDa, the isoelectric point was 5.35-7.68. Members of BrNHX gene family mainly existed in vacuoles, the gene structure is complete, and the number of exons is 11-22. The secondary structures of the proteins encoded by the NHX gene family in Chinese cabbage had alpha helix, beta turn and random coil, and the alpha helix occurred more frequently. Quantitative real-time PCR (qRT-PCR) analysis showed that the gene family members had different responses to high temperature, low temperature, drought and salt stress, and their expression levels differed significantly in different time periods. BrNHX02 and BrNHX09 had the most significant responses to these four stresses, and their expression levels were significantly up-regulated at 72 h after treatments, which could be used as candidate genes to further verify their functions.
Genome, Plant ; Multigene Family ; Stress, Physiological/genetics* ; Brassica/metabolism* ; Gene Expression Regulation, Plant ; Phylogeny ; Plant Proteins/metabolism*

OBJECTIVE: AP2/ERF (APETALA2/ethylene-responsive factor) superfamily is one of the largest gene families in plants and has been reported to participate in various biological processes, such as the regulation of biosynthesis of active lignan. However, few studies have investigated the genome-wide role of the AP2/ERF superfamily in Isatis indigotica. This study establishes a complete picture of the AP2/ERF superfamily in I. indigotica and contributes valuable information for further functional characterization of IiAP2/ERF genes and supports further metabolic engineering. METHODS: To identify the IiAP2/ERF superfamily genes, the AP2/ERF sequences from Arabidopsis thaliana and Brassica rapa were used as query sequences in the basic local alignment search tool. Bioinformatic analyses were conducted to investigate the protein structure, motif composition, chromosome location, phylogenetic relationship, and interaction network of the IiAP2/ERF superfamily genes. The accuracy of omics data was verified by quantitative polymerase chain reaction and heatmap analyses. RESULTS: One hundred and twenty-six putative IiAP2/ERF genes in total were identified from the I. indigotica genome database in this study. By sequence alignment and phylogenetic analysis, the IiAP2/ERF genes were classified into 5 groups including AP2, ERF, DREB (dehydration-responsive element-binding factor), Soloist and RAV (related to abscisic acid insensitive 3/viviparous 1) subfamilies. Among which, 122 members were unevenly distributed across seven chromosomes. Sequence alignment showed that I. indigotica and A. thaliana had 30 pairs of orthologous genes, and we constructed their interaction network. The comprehensive analysis of gene expression pattern in different tissues suggested that these genes may play a significant role in organ growth and development of I. indigotica. Members that may regulate lignan biosynthesis in roots were also preliminarily identified. Ribonucleic acid sequencing analysis revealed that the expression of 76 IiAP2/ERF genes were up- or down-regulated under salt or drought treatment, among which, 33 IiAP2/ERF genes were regulated by both stresses. CONCLUSION This study undertook a genome-wide characterization of the AP2/ERF superfamily in I. indigotica, providing valuable information for further functional characterization of IiAP2/ERF genes and discovery of genetic targets for metabolic engineering.
Abscisic Acid ; Isatis/genetics* ; Multigene Family ; Phylogeny ; Homeodomain Proteins/genetics* ; Genome, Plant

The CRISPR/Cas9 based prime editing (PE) technique enables all 12 types of base substitutions and precise small DNA deletions or insertions without generating DNA double-strand breaks. Prime editing has been successfully applied in plants and plays important roles in plant precision breeding. Although plant prime editing (PPE) can substantially expand the scope and capabilities of precise genome editing in plants, its editing efficiency still needs to be further improved. Here, we review the development of PPE technique, and introduce structural composition, advantages and limitations of PPE. Strategies to improve the PPE editing efficiency, including the T_m-directed PBS length design, the RT template length, the dual-pegRNA strategy, the PlantPegDesigner website, and the strategies for optimizing the target proteins of PPE, were highlighted. Finally, the prospects of future development and application of PPE were discussed.
CRISPR-Cas Systems/genetics* ; DNA ; Gene Editing ; Genome, Plant/genetics* ; Plant Breeding ; Plants/genetics*

Ligustri Lucidi Fructus, the sun-dried mature fruit of Ligustrum lucidum, is cool, plain, sweet, and bitter, which can be used as both food and medicine, with the effects of improving vision, blacking hair, and tonifying liver and kidney. It takes effect slowly. However, little is known about the genetic information of the medicinal plant and it is still a challenge to distinguish Ligustrum species. In this study, the complete chloroplast genome of L. lucidum was obtained by genome skimming and then compared with that of five other Ligustrum species, which had been reported. This study aims to evaluate the interspecific variation of chloroplast genome within the genus and develop molecular markers for species identification of the genus. The result showed that the chloroplast genome of L. lucidum was 162 162 bp with a circular quadripartite structure of two single-copy regions separated by a pair of inverted repeats. The Ligustrum chloroplast genomes were conserved with small interspecific difference. Comparative analysis of six Ligustrum chloroplast genomes revealed three variable regions(rbcL-accD, ycf1a, and ycf1b), and ycf1a and ycf1b can be used as the species-specific DNA barcode for Ligustrum. Phylogeny analysis provided the best resolution of Ligustrum and supported that L. lucidum was sister to L. gracile. This study clarified the genetic diversity of L. lucidum from provenance, which can serve as a reference for further analysis of pharmacological differences and breeding of excellent varieties with stable drug effects.
Fruit ; Genome, Chloroplast ; Ligustrum/genetics* ; Phylogeny ; Plant Breeding

Plants with alien genomic components (alien chromosomes / chromosomal fragments / genes) are important materials for genomic research and crop improvement. To date, four strategies based on trait observation, chromosome analysis, specific proteins, and DNA sequences have been developed for the identification of alien genomic components. Among them, DNA sequence-based molecular markers are mainly used to identify alien genomic components. This review summarized several molecular markers for identification of alien genomic components in wheat, cabbage and other important crops. We also compared the characteristics of nine common molecular markers, such as simple sequence repeat (SSR), insertion-deletion (InDel) and single nucleotide polymorphism (SNP). In general, the accuracy of using a combination of different identification methods is higher than using a single identification method. We analyzed the application of different combination of identification methods, and provided the best combination for wheat, brassica and other crops. High-throughput detection can be easily achieved by using the new generation molecular markers such as InDel and SNP, which can be used to determine the precise localization of alien introgression genes. To increase the identification efficiency, other new identification methods, such as microarray comparative genomic hybridization (array-CGH) and suppression subtractive hybridization (SSH), may also be included.
Chromosomes, Plant ; Comparative Genomic Hybridization ; Genome, Plant/genetics* ; Genomics ; Triticum/genetics*

The dynamic activity of transposable elements (TEs) contributes to the vast diversity of genome size and architecture among plants. Here, we examined the genomic distribution and transposition activity of long terminal repeat retrotransposons (LTR-RTs) in Arabidopsis thaliana (Ath) and three of its relatives, Arabidopsis lyrata (Aly), Eutrema salsugineum (Esa), and Schrenkiella parvula (Spa), in Brassicaceae. Our analyses revealed the distinct evolutionary dynamics of Gypsyretrotransposons, which reflects the different patterns of genome size changes of the four species over the past million years. The rate of Gypsy transposition in Aly is approximately five times more rapid than that of Ath and Esa, suggesting an expanding Aly genome. Gypsy insertions in Esa are strictly confined to pericentromeric heterochromatin and associated with dramatic centromere expansion. In contrast, Gypsy insertions in Spa have been largely suppressed over the last million years, likely as a result of a combination of an inherent molecular mechanism of preferential DNA removal and purifying selection at Gypsy elements. Additionally, species-specific clades of Gypsy elements shaped the distinct genome architectures of Aly and Esa.
Brassicaceae/genetics* ; Evolution, Molecular ; Genome Size ; Genome, Plant ; Genomics ; Phylogeny ; Retroelements ; Species Specificity