Adaptive evolution of chloroplast division mechanisms during plant terrestrialization.

Despite extensive research, the origin and evolution of the chloroplast division machinery remain unclear. Here, we employ recently sequenced genomes and transcriptomes of Archaeplastida clades to identify the core components of chloroplast division and reconstruct their evolutionary histories, respectively. Our findings show that complete division ring structures emerged in Charophytes. We find that Glaucophytes experienced strong selection pressure, generating diverse variants adapted to the changing terrestrial environments. By integrating the functions of chloroplast division genes (CDGs) annotated in a workflow developed using large-scale multi-omics data, we further show that dispersed duplications acquire more species-specific functions under stronger selection pressures. Notably, PARC6, a dispersed duplicate CDG, regulates leaf color and plant growth in Solanum lycopersicum, demonstrating neofunctionalization. Our findings provide an integrated perspective on the functional evolution of chloroplast division machinery and highlight the potential of dispersed duplicate genes as the primary source of adaptive evolution of chloroplast division.

Data-independent acquisition-based global phosphoproteomics reveal the diverse roles of casein kinase 1 in plant development.

Casein kinase 1 (CK1) is serine/threonine protein kinase highly conserved among eukaryotes, and regulates multiple developmental and signaling events through phosphorylation of target proteins. Arabidopsis early flowering 1 (EL1)-like (AELs) are plant-specific CK1s with varied functions, but identification and validation of their substrates is a major bottleneck in elucidating their physiological roles. Here, we conducted a quantitative phosphoproteomic analysis in data-independent acquisition mode to systematically identify CK1 substrates. We extracted proteins from seedlings overexpressing individual AEL genes (AEL1/2/3/4-OE) or lacking AEL function (all ael single mutants and two triple mutants) to identify the high-confidence phosphopeptides with significantly altered abundance compared to wild-type Col-0. Among these, we selected 3985 phosphopeptides with higher abundance in AEL-OE lines or lower abundance in ael mutants compared with Col-0 as AEL-upregulated phosphopeptides, and defined 1032 phosphoproteins. Eight CK1s substrate motifs were enriched among AEL-upregulated phosphopeptides and verified, which allowed us to predict additional candidate substrates and functions of CK1s. We functionally characterized a newly identified substrate C3H17, a CCCH-type zinc finger transcription factor, through biochemical and genetic analyses, revealing a role for AEL-promoted C3H17 protein stability and transactivation activity in regulating embryogenesis. As CK1s are highly conserved across eukaryotes, we searched the rice, mouse, and human protein databases using newly identified CK1 substrate motifs, yielding many more candidate substrates than currently known, largely expanding our understanding of the common and distinct functions exerted by CK1s in Arabidopsis and humans, facilitating future mechanistic studies of CK1-mediated phosphorylation in different species.

The Tartary buckwheat bHLH gene ALCATRAZ contributes to silique dehiscence in Arabidopsis thaliana.

Tartary buckwheat is popular because of its rich nutrients. However, the difficulty in shelling restricts food production. The gene ALCATRAZ (AtALC) plays a key role in silique dehiscence in Arabidopsis thaliana. In this study, an atalc mutant was obtained by CRISPR/Cas9, and a FtALC gene homologous to AtALC was complemented into the atalc mutant to verify its function. Phenotypic observations showed that three atalc mutant lines did not dehiscence, while ComFtALC lines recovered the dehiscence phenotype. The contents of lignin, cellulose, hemicellulose, and pectin in the siliques of all the atalc mutant lines were significantly higher than those in the wild-type and ComFtALC lines. Moreover, FtALC was found to regulate the expression of cell wall pathway genes. Finally, the interaction of FtALC with FtSHP and FtIND was verified by yeast two-hybrid, bimolecular fluorescent complimentary (BIFC) and firefly luciferase completion imaging assays (LCIs). Our findings enrich the silique regulatory network and lay the foundation for the cultivation of easily shelled tartary buckwheat varieties.

A cross-species co-functional gene network underlying leaf senescence.

The complex leaf senescence process is governed by various levels of transcriptional and translational regulation. Several features of the leaf senescence process are similar across species, yet the extent to which the molecular mechanisms underlying the process of leaf senescence are conserved remains unclear. Currently used experimental approaches permit the identification of individual pathways that regulate various physiological and biochemical processes; however, the large-scale regulatory network underpinning intricate processes like leaf senescence cannot be built using these methods. Here, we discovered a series of conserved genes involved in leaf senescence in a common horticultural crop (Solanum lycopersicum), a monocot plant (Oryza sativa), and a eudicot plant (Arabidopsis thaliana) through analyses of the evolutionary relationships and expression patterns among genes. Our analyses revealed that the genetic basis of leaf senescence is largely conserved across species. We also created a multi-omics workflow using data from more than 10 000 samples from 85 projects and constructed a leaf senescence-associated co-functional gene network with 2769 conserved, high-confidence functions. Furthermore, we found that the mitochondrial unfolded protein response (UPRmt) is the central biological process underlying leaf senescence. Specifically, UPRmt responds to leaf senescence by maintaining mitostasis through a few cross-species conserved transcription factors (e.g. NAC13) and metabolites (e.g. ornithine). The co-functional network built in our study indicates that UPRmt figures prominently in cross-species conserved mechanisms. Generally, the results of our study provide new insights that will aid future studies of leaf senescence.

Spatiotemporal distribution characteristics of PM2.5 concentration in China from 2000 to 2018 and its impact on population.

PM2.5 is an important indicator reflecting changes in air quality. In recent years, affected by climate change and human activities, the problem of environmental pollution has become more and more prominent. In this study, the PM2.5 data from 2000 to 2018 obtained by satellite remote sensing inversion algorithm were selected to analyze the temporal and spatial distribution of PM2.5 in China. The results show that the areas with higher PM2.5 concentrations were mainly in the North China, the Sichuan Basin, and the Tarim Basin. The areas with a significant increase in PM2.5 were mainly in the Northeast China, while the areas with a significant decrease were mainly in the Sichuan Basin and southeastern Gansu. The change of PM2.5 in southern China was not significantly correlated with the change of population and economy, while PM2.5 in Northeast China increases with the increase of population and economy. In 2000, 2005, 2010, and 2015, the proportion of the population polluted by PM2.5 was 8.65%, 7.2%, 22.99%, and 9.75%, respectively. The year with the highest percentage (37.63%) of population when air quality reached EXCELLENT was 2015. When the PM2.5 spatial cluster number was six, it can better reflect the PM2.5 spatial distribution state. The places with large changes in PM2.5 spatial clustering were mainly in the Northeast China, Sichuan Basin, and Tarim Basin, which were also areas with large changes in PM2.5. This study provides an important reference for atmospheric environmental monitoring and protection.

Influence and prediction of PM2.5 through multiple environmental variables in China.

Fine particulate matter (PM2.5) is an important indicator to measure the degree of air pollution. With the pursuit of sustainable development of China's economy and society, air pollution has been paid more and more attention. The spatial distribution of PM2.5 is affected by multiple factors. In this study, we selected Normalized Difference Vegetation Index (NDVI), precipitation, temperature, wind speed and elevation data to analyze the impact of each variable on PM2.5 in different regions of China. The results show that the high-value areas of PM2.5 were mainly concentrated in the North China Plain, the middle and lower reaches of the Yangtze River Plain, the Sichuan Basin, and the Tarim Basin. PM2.5 showed an upward trend in North China, Northeast China and Northwest China, while in most of South China, especially the Sichuan Basin, PM2.5 showed a downward trend. Therefore, the northern region of China needs to take measures to curb the growth of PM2.5. In Northwest China, wind speed and temperature had a greater impact on PM2.5. In North China, wind speed had a greater impact on PM2.5. In southern China, temperature and NDVI had a greater impact on PM2.5. The deep learning model can better simulate the spatial distribution of PM2.5 based on the selected variables. The clustering effect of single variable is better than multivariate spatial information clustering based on principal component analysis (PCA). It is difficult to explain which variable has the greatest impact on PCA clustering. This study can provide an important reference for PM2.5 prevention and control in different regions of China.

Integrated network analyses identify MYB4R1 neofunctionalization in the UV-B adaptation of Tartary buckwheat.

A hallmark of adaptive evolution is innovation in gene function, which is associated with the development of distinct roles for genes during plant evolution; however, assessing functional innovation over long periods of time is not trivial. Tartary buckwheat (Fagopyrum tataricum) originated in the Himalayan region and has been exposed to intense UV-B radiation for a long time, making it an ideal species for studying novel UV-B response mechanisms in plants. Here, we developed a workflow to obtain a co-functional network of UV-B responses using data from more than 10,000 samples in more than 80 projects with multi-species and multi-omics data. Dissecting the entire network revealed that flavonoid biosynthesis was most significantly related to the UV-B response. Importantly, we found that the regulatory factor MYB4R1, which resides at the core of the network, has undergone neofunctionalization. In vitro and in vivo experiments demonstrated that MYB4R1 regulates flavonoid and anthocyanin accumulation in response to UV-B in buckwheat by binding to L-box motifs in the FtCHS, FtFLS, and FtUFGT promoters. We used deep learning to develop a visual discrimination model of buckwheat flavonoid content based on natural populations exposed to global UV-B radiation. Our study highlights the critical role of gene neofunctionalization in UV-B adaptation.

Tartary buckwheat database (TBD): an integrative platform for gene analysis of and biological information on Tartary buckwheat.

Rice, wheat, corn, and potatoes are four crops that provide a daily source of nutrition for humans, but there are many problems that have been found with these crops. First, they lack amino acids and minerals which are necessary for balanced nutrition, and they also are grown very widely and as monocultures, which increases the risk of the human food system being destroyed by climate change. Thus, by introducing coarse cereals with good characteristics, we can enrich human food resources, realize agricultural diversification, improve dietary structure, and mitigate risks. Tartary buckwheat (Fagopyrum tataricum) is a widely cultivated edible and medicinal crop with unique nutritional and excellent economic value. It contains flavonoids, such as rutin and quercetin, which are not found in cereal crops. Rutin is a major flavonoid that can enhance blood flow and aid in the use of vitamin C and the production of collagen. In addition, such antioxidants have been shown to effectively reduce cholesterol levels, blood clots, and hypertension, particularly for the prevention of inflammatory liver injury (Middleton et al., 2000; Lee et al., 2013; Suzuki et al., 2014; Huang et al., 2016; Nishimura et al., 2016). Meanwhile, Tartary buckwheat can tolerate poor climate and acidic soils containing high amounts of aluminum, which is toxic to other crops (Wang et al., 2015). The self-pollination of Tartary buckwheat has resulted in a decrease in genomic heterozygosity, which is valuable for breeding and a stable production trait (Wang and Campbell, 2007). Therefore, Tartary buckwheat is an important minor crop, which is expected to become the target of many breeding efforts in the future.

A multilayered cross-species analysis of GRAS transcription factors uncovered their functional networks in plant adaptation to the environment.

Introduction: Environmental stress is both a major force of natural selection and a prime factor affecting crop qualities and yields. The impact of the GRAS [gibberellic acid-insensitive (GAI), repressor of GA1-3 mutant (RGA), and scarecrow (SCR)] family on plant development and the potential to resist environmental stress needs much emphasis. Objectives: This study aims to investigate the evolution, expansion, and adaptive mechanisms of GRASs of important representative plants during polyploidization. Methods: We explored the evolutionary characteristics of GRASs in 15 representative plant species by systematic biological analysis of the genome, transcriptome, metabolite, protein complex map and phenotype. Results: The GRAS family was systematically identified from 15 representative plant species of scientific and agricultural importance. The detection of gene duplication types of GRASs in all species showed that the widespread expansion of GRASs in these species was mainly contributed by polyploidization events. Evolutionary analysis reveals that most species experience independent genome-wide duplication (WGD) events and that interspecies GRAS functions may be broadly conserved. Polyploidy-related Chenopodium quinoa GRASs (CqGRASs) and Arabidopsis thaliana GRASs (AtGRASs) formed robust networks with flavonoid pathways by crosstalk with auxin and photosynthetic pathways. Furthermore, Arabidopsis thaliana population transcriptomes and the 1000 Plants (OneKP) project confirmed that GRASs are components of flavonoid biosynthesis, which enables plants to adapt to the environment by promoting flavonoid accumulation. More importantly, the GRASs of important species that may potentially improve important agronomic traits were mapped through TAIR and RARGE-II publicly available phenotypic data. Determining protein interactions and target genes contributes to determining GRAS functions. Conclusion: The results of this study suggest that polyploidy-related GRASs in multiple species may be a target for improving plant growth, development, and environmental adaptation.

Evolutionary research on the expansin protein family during the plant transition to land provides new insights into the development of Tartary buckwheat fruit.

BACKGROUND: Plant transitions to land require robust cell walls for regulatory adaptations and to resist changing environments. Cell walls provide essential plasticity for plant cell division and defense, which are often conferred by the expansin superfamily with cell wall-loosening functions. However, the evolutionary mechanisms of expansin during plant terrestrialization are unclear. RESULTS: Here, we identified 323 expansin proteins in 12 genomes from algae to angiosperms. Phylogenetic evolutionary, structural, motif gain and loss and Ka/Ks analyses indicated that highly conserved expansin proteins were already present in algae and expanded and purified after plant terrestrialization. We found that the expansion of the FtEXPA subfamily was caused by duplication events and that the functions of certain duplicated genes may have differentiated. More importantly, we generated space-time expression profiles and finally identified five differentially expressed FtEXPs in both large and small fruit Tartary buckwheat that may regulate fruit size by responding to indoleacetic acid. CONCLUSIONS: A total of 323 expansin proteins from 12 representative plants were identified in our study during terrestrialization, and the expansin family that originated from algae expanded rapidly after the plants landed. The EXPA subfamily has more members and conservative evolution in angiosperms. FtEXPA1, FtEXPA11, FtEXPA12, FtEXPA19 and FtEXPA24 can respond to indole-3-acetic acid (IAA) signals and regulate fruit development. Our study provides a blueprint for improving the agronomic traits of Tartary buckwheat and a reference for defining the evolutionary history of the expansin family during plant transitions to land.

Comprehensive multiomics analysis reveals key roles of NACs in plant growth and development and its environmental adaption mechanism by regulating metabolite pathways.

Abnormal environmental conditions induce polyploidization and exacerbate vulnerability to agricultural production. Polyploidization is a pivotal event for plant adaption to stress and the expansion of transcription factors. NACs play key roles in plant stress resistance and growth and development, but the adaptive mechanism of NACs during plant polyploidization remain to be explored. Here, we identified and analyzed NACs from 15 species and found that the expansion of NACs was contributed by polyploidization. The regulatory networks were systematically analyzed based on polyomics. NACs might influence plant phenotypes and were correlated with amino acids acting as nitrogen source, indicating that NACs play a vital role in plant development. More importantly, in quinoa and Arabidopsis thaliana, NACs enabled plants to resist stress by regulating flavonoid pathways, and the universality was further confirmed by the Arabidopsis population. Our study provides a cornerstone for future research into improvement of important agronomic traits by transcription factors in a changing global environment.

Cytochrome P450 family: Genome-wide identification provides insights into the rutin synthesis pathway in Tartary buckwheat and the improvement of agricultural product quality.

Flavonoids can not only help plants resist ultraviolet and pathogen attacks, but also show a wide range of therapeutic prospects for human health, including antioxidant, anti-inflammatory and anti-hypertension. Tartary buckwheat, as medicinal and food homologous crop, is rich in flavonoids, among which rutin may prevent liver damage. The one of the major objectives of Tartary buckwheat breeding is to cultivate varieties that have large fruits, high flavonoids and nutrient contents. Members of the cytochrome P450 monooxygenase (CYP) superfamily play a vital role in the synthesis of flavonoids, plant growth and development. Whole-genome analyses of the CYP family have been performed in several plants, but the CYP family has not been characterized in Tartary buckwheat. In this study, 285 FtCYPs were identified from the genome to improve the rutin content and quality of Tartary buckwheat. By exploring the structure, motif composition, tandem and segmental duplication events of FtCYPs, as well as evolutionary relationships with CYPs in other plants, we preliminarily screened potential FtCYPs regulating rutin synthesis, growth and development. The expression levels of the FtCYPs in different organs and fruits at various periods were measured. This study provides a solid foundation for verifying the function of FtCYPs, cultivating high rutin Tartary buckwheat varieties.

Genome-wide investigation of WRKY transcription factors in Tartary buckwheat (Fagopyrum tataricum) and their potential roles in regulating growth and development.

BACKGROUND: The WRKY gene family plays important roles in plant biological functions and has been identified in many plant species. With the publication of the Tartary buckwheat genome, the evolutionary characteristics of the WRKY gene family can be systematically explored and the functions of Fagopyrum tataricum WRKY (FtWRKY) genes in the growth and development of this plant also can be predicted. METHODS: In this study, the FtWRKY genes were identified by the BLASTP method, and HMMER, SMART, Pfam and InterPro were used to determine whether the FtWRKY genes contained conserved domains. The phylogenetic trees including FtWRKY and WRKY genes in other plants were constructed by the neighbor-joining (NJ) and maximum likelihood (ML) methods. The intron and exon structures of the FtWRKY genes were analyzed by the gene structure display server, and the motif compositions were analyzed by MEME. Chromosome location information of FtWRKY genes was obtained with gff files and sequencing files, and visualized by Circos, and the collinear relationship was analyzed by Dual synteny plotter software. The expression levels of 26 FtWRKY genes from different groups in roots, leaves, flowers, stems and fruits at the green fruit, discoloration and initial maturity stage were measured through quantitative real-time polymerase chain reaction (qRT-PCR) analysis. RESULTS: A total of 76 FtWRKY genes identified from the Tartary buckwheat genome were divided into three groups. FtWRKY genes in the same group had similar gene structures and motif compositions. Despite the lack of tandem-duplicated gene pairs, there were 23 pairs of segmental-duplicated gene pairs. The synteny gene pairs of FtWRKY genes and Glycine max WRKY genes were the most. FtWRKY42 was highly expressed in roots and may perform similar functions as its homologous gene AtWRKY75, playing a role in lateral root and hairy root formation. FtWRKY9, FtWRKY42 and FtWRKY60 were highly expressed in fruits and may play an important role in fruit development. CONCLUSION: We have identified several candidate FtWRKY genes that may perform critical functions in the development of Tartary buckwheat root and fruit, which need be verified through further research. Our study provides useful information on WRKY genes in regulating growth and development and establishes a foundation for screening WRKY genes to improve Tartary buckwheat quality.

Basic helix-loop-helix (bHLH) gene family in Tartary buckwheat (Fagopyrum tataricum): Genome-wide identification, phylogeny, evolutionary expansion and expression analyses.

Tartary buckwheat (Fagopyrum tataricum) a kind of edible and medicinal plant, is of great nutritional value. It is difficult to remove the hull of Tartary buckwheat fruit and breeding new easy-dehulled varieties has been one of the major breeding objectives. The bHLH gene family plays a vital role in plant growth and fruit dehiscence. In order to improve Tartary buckwheat breeding, we need to study the bHLH gene family for excavating genes with potential regulation of fruit development and dehiscence. Here, 164 Fagopyrum tataricum bHLH (FtbHLH) genes were identified. Analyses of gene structure and motif composition illustrate that the members of specific FtbHLH subfamily are relatively conserved. Synteny and phylogenetic analyses of bHLH genes in Tartary buckwheat and other plants lay a foundation for further exploring the evolutionary characteristic of the FtbHLH genes (FtbHLHs). qRT-PCR experiments showed that FtbHLHs expression patterns were different in plant organs, indicating that they may perform diverse functions. In addition, some genes that potentially regulate flower and fruit development and easy dehulling were screened out. Overall, this study will be helpful for further analyzing the biological function of FtbHLHs and provides clues for improving the genetic breeding and economic value of the Tartary buckwheat.

Genome-wide investigation of the heat shock transcription factor (Hsf) gene family in Tartary buckwheat (Fagopyrum tataricum).

BACKGROUND: Heat shock transcription factor (Hsfs) is widely found in eukaryotes and prokaryotes. Hsfs can not only help organisms resist high temperature, but also participate in the regulation of plant growth and development (such as involved in the regulation of seed maturity and affects the root length of plants). The Hsf gene was first isolated from yeast and then gradually found in plants and sequenced, such as Arabidopsis thaliana, rice, maize. Tartary buckwheat is a rutin-rich crop, and its nutritional value and medicinal value are receiving more and more attention. However, there are few studies on the Hsf genes in Tartary buckwheat. With the whole genome sequence of Tartary buckwheat, we can effectively study the Hsf gene family in Tartary buckwheat. RESULTS: According to the study, 29 Hsf genes of Tartary buckwheat (FtHsf) were identified and renamed according to location of FtHsf genes on chromosome after removing a redundant gene. Therefore, only 29 FtHsf genes truly had the functional characteristics of the FtHsf family. The 29 FtHsf genes were located on 8 chromosomes of Tartary buckwheat, and we found gene duplication events in the FtHsf gene family, which may promote the expansion of the FtHsf gene family. Then, the motif compositions and the evolutionary relationship of FtHsf proteins and the gene structures, cis-acting elements in the promoter, synteny analysis of FtHsf genes were discussed in detail. What's more, we found that the transcription levels of FtHsf in different tissues and fruit development stages were significantly different by quantitative real-time PCR (qRT-PCR), implied that FtHsf may differ in function. CONCLUSIONS: In this study, only 29 Hsf genes were identified in Tartary buckwheat. Meanwhile, we also classified the FtHsf genes, and studied their structure, evolutionary relationship and the expression pattern. This series of studies has certain reference value for the study of the specific functional characteristics of Tartary buckwheat Hsf genes and to improve the yield and quality of Tartary buckwheat in the future.

MYB Gene Family in Potato (Solanum tuberosum L.): Genome-Wide Identification of Hormone-Responsive Reveals Their Potential Functions in Growth and Development.

As an important nongrain crop, the growth and yield of potato (Solanum tuberosum L.) is often affected by an unfavorable external environment in the process of cultivation. The MYB family is one of the largest and most important gene families, participating in the regulation of plant growth and development and response to abiotic stresses. Several MYB genes in potato that regulate anthocyanin synthesis and participate in abiotic stress responses have been identified. To identify all Solanum tuberosum L. MYB (StMYB) genes involved in hormone or stress responses to potentially regulate potato growth and development, we identified the MYB gene family at the genome-wide level. In this work, 158 StMYB genes were found in the potato genome. According to the amino acid sequence of the MYB domain and gene structure, the StMYB genes were divided into R2R3-MYB and R1R2R3-MYB families, and the R2R3-MYB family was divided into 20 subgroups (SGs). The expression of 21 StMYB genes from different SGs in roots, stems, leaves, flowers, shoots, stolons, young tubers, and mature tubers was determined by quantitative real-time polymerase chain reaction (qRT-PCR). The expression patterns of StMYB genes in potatoes treated with abscisic acid (ABA), indole-3-acetic acid (IAA), gibberellin acid 3 (GA3), NaCl, mannitol, and heat were also measured. We have identified several potential candidate genes that regulate the synthesis of potato flavonoids or participate in hormone or stress responses. This work provides a comprehensive understanding of the MYB family in potato and will lay a foundation for the future investigation of the potential functions of StMYB genes in the growth and development of potato.

Genome-wide identification and expression analysis of the trihelix transcription factor family in tartary buckwheat (Fagopyrum tataricum).

BACKGROUND: In the study, the trihelix family, also referred to as GT factors, is one of the transcription factor families. Trihelix genes play roles in the light response, seed maturation, leaf development, abiotic and biological stress and other biological activities. However, the trihelix family in tartary buckwheat (Fagopyrum tataricum), an important usable medicinal crop, has not yet been thoroughly studied. The genome of tartary buckwheat has recently been reported and provides a theoretical basis for our research on the characteristics and expression of trihelix genes in tartary buckwheat based at the whole level. RESULTS: In the present study, a total of 31 FtTH genes were identified based on the buckwheat genome. They were named from FtTH1 to FtTH31 and grouped into 5 groups (GT-1, GT-2, SH4, GTγ and SIP1). FtTH genes are not evenly distributed on the chromosomes, and we found segmental duplication events of FtTH genes on tartary buckwheat chromosomes. According to the results of gene and motif composition, FtTH located in the same group contained analogous intron/exon organizations and motif organizations. qRT-PCR showed that FtTH family members have multiple expression patterns in stems, roots, leaves, fruits, and flowers and during fruit development. CONCLUSIONS: Through our study, we identified 31 FtTH genes in tartary buckwheat and synthetically further analyzed the evolution and expression pattern of FtTH proteins. The structure and motif organizations of most genes are conserved in each subfamily, suggesting that they may be functionally conserved. The FtTH characteristics of the gene expression patterns indicate functional diversity in the time and space in the tartary buckwheat life process. Based on the discussion and analysis of FtTH gene function, we screened some genes closely related to the growth and development of tartary buckwheat. This will help us to further study the function of FtTH genes through experimental exploration in tartary buckwheat growth and improve the fruit of tartary buckwheat.

Genome-wide identification, expression analysis and functional study of the GRAS gene family in Tartary buckwheat (Fagopyrum tataricum).

BACKGROUND: GRAS are plant-specific transcription factors that play important roles in plant growth and development. Although the GRAS gene family has been studied in many plants, there has been little research on the GRAS genes of Tartary buckwheat (Fagopyrum tataricum), which is an important crop rich in rutin. The recently published whole genome sequence of Tartary buckwheat allows us to study the characteristics and expression patterns of the GRAS gene family in Tartary buckwheat at the genome-wide level. RESULTS: In this study, 47 GRAS genes of Tartary buckwheat were identified and divided into 10 subfamilies: LISCL, HAM, DELLA, SCR, PAT1, SCL4/7, LAS, SHR, SCL3, and DLT. FtGRAS genes were unevenly distributed on 8 chromosomes, and members of the same subfamily contained similar gene structures and motif compositions. Some FtGRAS genes may have been produced by gene duplications; tandem duplication contributed more to the expansion of the GRAS gene family in Tartary buckwheat. Real-time PCR showed that the transcription levels of FtGRAS were significantly different in different tissues and fruit development stages, implying that FtGRAS might have different functions. Furthermore, an increase in fruit weight was induced by exogenous paclobutrazol, and the transcription level of the DELLA subfamily member FtGRAS22 was significantly upregulated during the whole fruit development stage. Therefore, FtGRAS22 may be a potential target for molecular breeding or genetic editing. CONCLUSIONS: Collectively, this systematic analysis lays a foundation for further study of the functional characteristics of GRAS genes and for the improvement of Tartary buckwheat crops.

Genome-wide identification of the SPL gene family in Tartary Buckwheat (Fagopyrum tataricum) and expression analysis during fruit development stages.

BACKGROUND: SPL (SQUAMOSA promoter binding protein-like) is a class of plant-specific transcription factors that play important roles in many growth and developmental processes, including shoot and inflorescence branching, embryonic development, signal transduction, leaf initiation, phase transition, and flower and fruit development. The SPL gene family has been identified and characterized in many species but has not been well studied in tartary buckwheat, which is an important edible and medicinal crop. RESULTS: In this study, 24 Fagopyrum tataricum SPL (FtSPL) genes were identified and renamed according to the chromosomal distribution of the FtSPL genes. According to the amino acid sequence of the SBP domain and gene structure, the SPL genes were divided into eight groups (group I to group VII) by phylogenetic tree analysis. A total of 10 motifs were detected in the tartary buckwheat SPL genes. The expression patterns of 23 SPL genes in different tissues and fruits at different developmental stages (green fruit stage, discoloration stage and initial maturity stage) were determined by quantitative real-time polymerase chain reaction (qRT-PCR). CONCLUSIONS: The tartary buckwheat genome contained 24 SPL genes, and most of the genes were expressed in different tissues. qRT-PCR showed that FtSPLs played important roles in the growth and development of tartary buckwheat, and genes that might regulate flower and fruit development were preliminarily identified. This work provides a comprehensive understanding of the SBP-box gene family in tartary buckwheat and lays a significant foundation for further studies on the functional characteristics of FtSPL genes and improvement of tartary buckwheat crops.

Genome-wide identification, phylogeny, evolutionary expansion and expression analyses of bZIP transcription factor family in tartaty buckwheat.

BACKGROUND: In reported plants, the bZIP family is one of the largest transcription factor families. bZIP genes play roles in the light signal, seed maturation, flower development, cell elongation, seed accumulation protein, abiotic and biological stress and other biological processes. While, no detailed identification and genome-wide analysis of bZIP family genes in Fagopyum talaricum (tartary buckwheat) has previously been published. The recently reported genome sequence of tartary buckwheat provides theoretical basis for us to study and discuss the characteristics and expression of bZIP genes in tartary buckwheat based on the whole genome. RESULTS: In this study, 96 FtbZIP genes named from FtbZIP1 to FtbZIP96 were identified and divided into 11 subfamilies according to their genetic relationship with 70 bZIPs of A. thaliana. FtbZIP genes are not evenly distributed on the chromosomes, and we found tandem and segmental duplication events of FtbZIP genes on 8 tartary buckwheat chromosomes. According to the results of gene and motif composition, FtbZIP located in the same group contained analogous intron/exon organizations and motif composition. By qRT-PCR, we quantified the expression of FtbZIP members in stem, root, leaf, fruit, and flower and during fruit development. Exogenous ABA treatment increased the weight of tartary buckwheat fruit and changed the expressions of FtbZIP genes in group A. CONCLUSIONS: Through our study, we identified 96 FtbZIP genes in tartary buckwheat and synthetically further analyzed the structure composition, evolution analysis and expression pattern of FtbZIP proteins. The expression pattern indicates that FtbZIP is important in the course of plant growth and development of tartary buckwheat. Through comprehensively analyzing fruit weight and FtbZIP genes expression after ABA treatment and endogenous ABA content of tartary buckwheat fruit, ABA may regulate downstream gene expression by regulating the expression of FtPinG0003523300.01 and FtPinG0003196200.01, thus indirectly affecting the fruit development of tartary buckwheat. This will help us to further study the function of FtbZIP genes in the tartary buckwheat growth and improve the fruit of tartary buckwheat.