Histology, physiology, and transcriptomic and metabolomic profiling reveal the developmental dynamics of annual shoots in tree peonies (Paeonia suffruticosa Andr.)

The development of tree peony annual shoots is characterized by“withering”,which is related to whether there are bud points in the leaf axillaries of annual shoots.However,the mechanism of“withering”in tree peony is still unclear.In this study,Paeonia ostii‘Fengdan’and P.suffruticosa‘Luoyanghong’were used to investigate dynamic changes of annual shoots through anatomy,physiology,transcriptome,and metabolome.The results demonstrated that the developmental dynamics of annual shoots of the two cultivars were comparable.The withering degree of P.suffruticosa‘Luoyanghong’was higher than that of P.ostii‘Fengdan’,and their upper internodes of annual flowering shoots had a lower degree of lignin deposition,cellulose,C/N ratio,showing no obvious sclerenchyma,than the bottom ones and the whole internodes of vegetative shoot,which resulted in the“withering”of upper internodes.A total of 36 phytohormone metabolites were detected,of which 33 and 31 were detected in P.ostii‘Fengdan’and P.suffruticosa‘Luoyanghong’,respectively.In addition,302 and 240 differentially expressed genes related to lignin biosynthesis,carbon and nitrogen metabolism,plant hormone signal transduction,and zeatin biosynthesis were screened from the two cultivars.Furtherly,36 structural genes and 40 transcription factors associated with the development of annual shoots were highly co-expressed,and eight hub genes involved in this developmental process were identified.Consequently,this study explained the developmental dynamic on the varied annual shoots through multi-omics,providing a theoretical foundation for germplasm innovation and the mechanized harvesting of tree peony annual shoots.

In situ measurements of winter wheat diurnal changes in photosynthesis and environmental factors reveal new insight into photosynthesis improvement by super-high-yield cultivation

In past 30 years, the wheat yield per unit area of China has increased by 79%. The super-high-yield(SH) cultivation played an important role in improving the wheat photosynthesis and yield. In order to find the ecophysiological mechanism underneath the high photosynthesis of SH cultivation, in situ diurnal changes in the photosynthetic gas exchange and chlorophyll(Chl) a fluorescence of field-grown wheat plants during the grain-filling stage and environmental factors were investigated. During the late grain-filling stage at 24 days after anthesis(DAA), the diurnal changes in net CO_(2) assimilation rate were higher under SH treatment than under high-yield(H) treatment. From 8 to 24 DAA, the actual quantum yield of photosystem II(PSII) electron transport in the light-adapted state(ΦPSII) in the flag leaves at noon under SH treatment were significantly higher than those under H treatment. The leaf temperature, soil temperature and soil moisture were better suited for higher rates of leaf photosynthesis under SH treatment than those under H treatment at noon. Such diurnal changes in environmental factors in wheat fields could be one of the mechanisms for the higher biomass and yield under SH cultivation than those under H cultivation. ΦPSII and CO_(2) exchange rate in wheat flag leaves under SH and H treatments had a linear correlation which could provide new insight to evaluate the wheat photosynthesis performance under different conditions.

GreenPhos,a universal method for in-depth measurement of plant phosphoproteomes with high quantitative reproducibility

Protein phosphorylation regulates a variety of important cellular and physiological processes in plants.In-depth profiling of plant phosphoproteomes has been more technically challenging than that of animal phosphoproteomes.This is largely due to the need to improve protein extraction efficiency from plant cells,which have a dense cell wall,and to minimize sample loss resulting from the stringent sample clean-up steps required for the removal of a large amount of biomolecules interfering with phosphopeptide purification and mass spectrometry analysis.To this end,we developed a method with a streamlined workflow for highly efficient purification of phosphopeptides from tissues of various green organisms including Arabidopsis,rice,tomato,and Chlamydomonas reinhardtii,enabling in-depth identification with high quantitative reproducibility of about 11000 phosphosites,the greatest depth achieved so far with single liquid chromatography-mass spectrometry(LC-MS)runs operated in a data-dependent acquisition(DDA)mode.The mainstay features of the method are the minimal sample loss achieved through elimination of sample clean-up before protease digestion and of desalting before phosphopeptide enrichment and hence the dramatic increases of time-and cost-effectiveness.The method,named GreenPhos,combined with single-shot LC-MS,enabled in-depth quantitative identification of Arabidopsis phosphoproteins,including differentially phosphorylated spliceosomal proteins,at multiple time points during salt stress and a number of kinase substrate motifs.GreenPhos is expected to serve as a universal method for purification of plant phosphopeptides,which,if samples are further fractionated and analyzed by multiple LC-MS runs,could enable measurement of plant phosphoproteomes with an unprecedented depth using a given mass spectrometry technology.

Characteristics of N^(6)-methyladenosine Modification During Sexual Reproduction of Chlamydomonas reinhardtii

The unicellular green alga Chlamydomonas reinhardtii(hereafter Chlamydomonas)possesses both plant and animal attributes,and it is an ideal model organism for studying fundamental processes such as photosynthesis,sexual reproduction,and life cycle.N^(6)-methyladenosine(m^(6)A)is the most prevalent mRNA modification,and it plays important roles during sexual reproduction in animals and plants.However,the pattern and function of m^(6)A modification during the sexual reproduction of Chlamydomonas remain unknown.Here,we performed transcriptome and methylated RNA immunoprecipitation sequencing(MeRIP-seq)analyses on six samples from different stages during sexual reproduction of the Chlamydomonas life cycle.The results show that m^(6)A modification frequently occurs at the main motif of DRAC(D=G/A/U,R=A/G)in Chlamydomonas mRNAs.Moreover,m^(6)A peaks in Chlamydomonas mRNAs are mainly enriched in the 30 untranslated regions(30 UTRs)and negatively correlated with the abundance of transcripts at each stage.In particular,there is a significant negative correlation between the expression levels and the m^(6)A levels of genes involved in the microtubule-associated pathway,indicating that m^(6)A modification influences the sexual reproduction and the life cycle of Chlamydomonas by regulating microtubule-based movement.In summary,our findings are the first to demonstrate the distribution and the functions of m^(6)A modification in Chlamydomonas mRNAs and provide new evolutionary insights into m^(6)A modification in the process of sexual reproduction in other plant organisms.

The Relationship Between Stomatal Movement and Light Intensity Gradient in Three Dendrobium Species Compared with Typical CAM Plants

There is a close relationship between crassulacean acid metabolism and drought tolerance,and a great number of landscape plants which consume less water are necessary to build economic garden.In order to provide the basis for selecting drought-tolerant landscape plants,five species of plants were employed,including Dendrobium chrysotoxum,D.nobile,D.primulinum,Kalanchoblossfeldiana and K.daigremontiana.Exposed to different intensities of light,various samples were collected.The slices were prepared via different techniques.Stomatal movements and stomatal complex structures were observed by scanning electronic microscope and confocal laser scanning microscope.The results indicated that the slices made rapidly from fresh leaves were conductive to inspecting actual stomatal movements and stomatal complex structures as soon as possible.It was found that the stomatal movement of K.daigremontiana,K.blossfeldiana and D.primulinum displayed typical characteristics of crassulacean acid metabolism,while that of D.chrysotoxum and D.nobile did not exhibited obvious characteristics of crassulacean acid metabolism.

Regulation of chloroplast protein degradation

Chloroplasts are unique organelles that not only provide sites for photosynthesis and many metabolic processes,but also are sensitive to various environmental stresses.Chloroplast proteins are encoded by genes from both nuclear and chloroplast genomes.During chloroplast development and responses to stresses,the robust protein quality control systems are essential for regulation of protein homeostasis and the integrity of chloroplast proteome.In this review,we summarize the regulatory mechanisms of chloroplast protein degradation refer to protease system,ubiquitin-proteasome system,and the chloroplast autophagy.These mechanisms symbiotically play a vital role in chloroplast development and photosynthesis under both normal or stress conditions.

Cryo-electron microscopy structure of the intact photosynthetic light-harvesting antenna-reaction center complex from a green sulfur bacterium

The photosynthetic reaction center complex(RCC)of green sulfur bacteria(GSB)consists of the membrane-imbedded RC core and the peripheric energy transmitting proteins called Fenna–Matthews–Olson(FMO).Functionally,FMO transfers the absorbed energy from a huge peripheral light-harvesting antenna named chlorosome to the RC core where charge separation occurs.In vivo,one RC was found to bind two FMOs,however,the intact structure of RCC as well as the energy transfer mechanism within RCC remain to be clarified.Here we report a structure of intact RCC which contains a RC core and two FMO trimers from a thermophilic green sulfur bacterium Chlorobaculum tepidum at 2.9A resolution by cryo-electron microscopy.The second FMO trimer is attached at the cytoplasmic side asymmetrically relative to the first FMO trimer reported previously.We also observed two new subunits(PscE and PscF)and the N-terminal transmembrane domain of a cytochrome-containing subunit(PscC)in the structure.These two novel subunits possibly function to facilitate the binding of FMOs to RC core and to stabilize the whole complex.A new bacteriochlorophyll(numbered as 816)was identified at the interspace between PscF and PscA-1,causing an asymmetrical energy transfer from the two FMO trimers to RC core.Based on the structure,we propose an energy transfer network within this photosynthetic apparatus.

Regulatory dynamics of the higher-plant PSI-LHCI supercomplex during state transitions

State transition is a fundamental light acclimation mechanism of photosynthetic organisms in response to the environmental light conditions.This process rebalances the excitation energy between photosystemI(PSl)and photosystem Il through regulated reversible binding of the light-harvesting complex Il(LHCll)to PSl.However,the structural reorganization of PSI-LHCI,the dynamic binding of LHCll,and the regulatory mechanisms underlying state transitions are less understood in higher plants.In this study,using cryoelectron microscopy we resolved the structures of PSI-LHCI in both state 1(PSI-LHCI-ST1)and state 2(PSILHCI-LHCll-ST2)from Arabidopsis thaliana.Combined genetic and functional analyses revealed novel contacts between Lhcb1 and PsaK that further enhanced the binding of the LHCll trimer to the PSI core with the known interactions between phosphorylated Lhcb2 and the PsaL/PsaH/PsaO subunits.Specifically,PsaO was absent in the PSI-LHCI-ST1 supercomplex but present in the PSI-LHCI-LHCIl-ST2 supercomplex,in which the PsaL/PsaK/PsaA subunits undergo several conformational changes to strengthen the binding of PsaO in ST2.Furthermore,the PSI-LHCI module adopts a more compact configuration with shorter Mg-to-Mg distances between the chlorophylls,which may enhance the energy transfer efficiency from the peripheral antenna to the PSl core in ST2.Collectively,our work provides novel structural and functional insights into the mechanisms of light acclimation during state transitions in higher plants.

The PPR protein PDM1 is involved in the processing of rpoA pre-mRNA in Arabidopsis thaliana

Pentatricopeptide repeat (PPR) proteins,containing tandem repeats of degenerate 35 amino acid motifs,are important for post-transcriptional chloroplast gene expression. In this study,we report the characterization of a pigment-deficient mutant 1 (pdm1) in Arabidopsis,which displays the albino phenotype. PDM1 contains 5 PPR motifs followed by a PLS domain. The levels of plastid-encoded polymerase-dependent chloroplast genes were reduced dramatically,whereas those of nucleus-encoded polymerase-dependent chloroplast genes increased in the mutant. In addition,the pattern of rpoA pre-mRNA was altered and the rpoA transcript was absent in pdm1. Thus,these results suggest that PDM1 is required for processing of rpoA pre-mRNA in Arabidop-sis.

A pair of light signaling factors FHY3 and FAR1 regulates plant immunity by modulating chlorophyll biosynthesis

Light and chloroplast function is known to affect the plant immune response; however, the underlying mechanism remains elusive. We previously demonstrated that two light signaling factors, FAR-RED ELONGATED HYPOCOTYL 3（FHY3）and FAR-RED IMPAIRED RESPONSE 1（FAR1）, regulate chlorophyll biosynthesis and seedling growth via controlling HEMB1 expression in Arabidopsis thaliana. In this study, we reveal that FHY3 and FAR1 are involved in modulating plant immunity. We showed that the fhy3 far1 double null mutant displayed high levels of reactive oxygen species and salicylic acid（SA） and increased resistance to Pseudomonas syringae pathogen infection. Microarray analysis revealed that a large proportion of pathogen-related genes, particularly genes encoding nucleotide-binding and leucine-rich repeat domain resistant proteins, are highly induced in fhy3 far1. Genetic studies indicated that the defects of fhy3 far1 can be largely rescued by reducing SA signaling or blocking SA accumulation, and by overexpression of HEMB1, which encodes a 5-aminolevulinic acid dehydratase in the chlorophyll biosynthetic pathway.Furthermore, we found that transgenic plants with reduced expression of HEMB1 exhibit a phenotype similar to fhy3 far1.Taken together, this study demonstrates an important role of FHY3 and FAR1 in regulating plant immunity, through integrating chlorophyll biosynthesis and the SA signaling pathway.

Arabidopsis FHY3 and FAR1 Regulate Light-Induced myo-Inositol Biosynthesis and Oxidative Stress Responses by Transcriptional Activation of MIPS1

myo-lnositol-l-phosphate synthase （MIPS） catalyzes the limiting step of inositol biosynthesis and has crucial roles in plant growth and development. In response to stress, the transcription of MIPS1 is induced and the biosynthesis of inositol or inositol derivatives is promoted by unknown mechanisms. Here, we found that the light signaling protein FAR-RED ELONGATED HYPOCOTYL3 （FHY3） and its homolog FAR- RED IMPAIRED RESPONSE1 （FAR1） regulate light-induced inositol biosynthesis and oxidative stress re- sponses by activating the transcription of MIPS1. Disruption of FHY3 and FAR1 caused light-induced cell death after dark-light transition, precocious leaf senescence, and increased sensitivity to oxidative stress. Reduction of salicylic acid （SA） accumulation by overexpression of SALICYLIC ACID 3-HYDROXYLASE largely suppressed the cell death phenotype of fhy3 far1 mutant plants, suggesting that FHY3- and FARl-mediated cell death is dependent on SA. Furthermore, comparative analysis of chromatin immuno- precipitation sequencing and microarray results revealed that FHY3 and FAR1 directly target both MIPS1 and MIPS2. The fhy3 far1 mutant plants showed severely decreased MIPS1/2 transcript levels and reduced inositol levels. Conversely, constitutive expression of MIPSl partially rescued the inositol contents, caused reduced transcript levels of SA-biosynthesis genes, and prevented oxidative stress in fhy3 far1. Taken together, our results indicate that the light signaling proteins FHY3 and FAR1 directly bind the promoter of MIPS1 to activate its expression and thereby promote inositol biosynthesis to prevent light-induced oxidative stress and SA-dependent cell death.

The role of light in regulating seed dormancy and germination^FA

Seed dormancy is an adaptive trait in plants. Breaking seed dormancy determines the timing of ger-mination and is, thereby essential for ensuring plant sur-vival and agricultural production. Seed dormancy and the subsequent germination are controlled by both internal cues (mainly hormones) and environmental signals. In the past few years, the roles of plant hormones in regulating seed dormancy and germination have been uncovered. However, we are only beginning to understand how light signaling pathways modulate seed dormancy and inter-action with endogenous hormones. In this review, we summarize current views of the molecular mechanisms by which light controls the induction, maintenance and re-lease of seed dormancy, as well as seed germination, by regulating hormone metabolism and signaling pathways.

mTERF5 Acts as a Transcriptional Pausing Factor to Positively Regulate Transcription of Chloroplast psbEFLJ

RNA polymerase transcriptional pausing represents a major checkpoint in transcription in bacteria and metazoans,but it is unknown whether this phenomenon occurs in plant organelles.Here,we report that transcriptional pausing occurs in chloroplasts.We found that mTERF5 specifically and positively regulates the transcription of chloroplast psbEFLJ in Arabidopsis thaliana that encodes four key subunits of photosystem II.We found that mTERF5 causes the plastid-encoded RNA polymerase(PEP)complex to pause at psbEFLJ by binding to the+30 to+51 region of double-stranded DNA.Moreover,we revealed that mTERF5 interacts with pTAC6,an essential subunit of the PEP complex,although pTAC6 is not involved in the transcriptional pausing at psbEFLJ.We showed that mTERF5 recruits additional pTAC6 to the transcriptionally paused region of psbEFLJ,and the recruited pTAC6 proteins could be assembled into the PEP complex to regulate psbEFLJ transcription.Taken together,our findings shed light on the role of transcriptional pausing in chloroplast transcription in plants.

Deg1 is involved in the degradation of the PsbO oxygen-evolving protein of photosystem Ⅱ in Arabidopsis

Deg1,a thylakoid lumen-localized protease,retains both chaperone and protease activities.The in vivo function of Deg1 has been shown to be involved not only in PSII assembly but also in the degradation of PSII reaction center protein D1.Here we used the transgenic plants with reduced Deg1 to examine whether the lumen-localized proteins are also the substrates of Deg1 in vivo.Our results showed that the transgenic plants accumulated degradation products of the PsbO protein while the levels of full-length PsbO were not affected.The PsbO degradation products could be efficiently degraded by the recombinant Deg1.These results suggest that Deg1 is involved in the degradation of the PsbO degradation fragments,but not in the initial cleavage event itself.

The Phytol Phosphorylation Pathway Is Essential for the Biosynthesis of Phylloquinone, which Is Required for Photosystem I Stability in Arabidopsis

Phytyl-diphosphate, which provides phytyl moieties as a common substrate in both tocopherol and phyllo- quinone biosynthesis, derives from de novo isoprenoid biosynthesis or a salvage pathway via phytol phos- phorylation. However, very little is known about the role and origin of the phytyl moiety for phylloquinone biosynthesis. Since VTE6, a phytyl-phosphate kinase, is a key enzyme for phytol phosphorylation, we char- acterized Arabidopsis vte6 mutants to gain insight into the roles of phytyl moieties in phylloquinone biosyn- thesis and of phylloquinone in photosystem I （PSI） biogenesis. The VTE6 knockout mutants vte6-1 and vte6-2 lacked detectable phylloquinone, whereas the phylloquinone content in the VTE6 knockdown mutant vte6-3 was 90% lower than that in wild-type. In vte6 mutants, PSI function was impaired and accu- mulation of the PSI complex was defective. The PSI core subunits PsaA/B were efficiently synthesized and assembled into the PSI complex in vte6-3. However, the degradation rate of PSI subunits in the assembled PSI complex was more rapid in vte6-3 than in wild-type. In vte6-3, PSI was more susceptible to high-light damage than in wild-type. Our results provide the first genetic evidence that the phytol phosphorylation pathway is essential for phylloquinone biosynthesis, and that phylloquinone is required for PSI complex stability.

Reversible SUMOylation of FHY1 Regulates Phytochrome A Signaling in Arabidopsis

In response to far-red light(FR),FAR-RED ELONGATED HYPOCOTYL 1(FHY1)transports the photoactivated phytochrome A(phyA),the primary FR photoreceptor,into the nucleus,where it initiates FR signaling in plants.Light promotes the 26S proteasome-mediated degradation of FHY1,which desensitizes FR signaling,but the underlying regulatory mechanism remains largely unknown.Here,we show that reversible SUMOylation of FHY1 tightly regulates this process.Lysine K32(K32)and K103 are major SUMOylation sites of FHY1.We found that FR exposure promotes the SUMOylation of FHY1,which accelerates its degradation.Furthermore,we discovered that ARABIDOPSIS SUMO PROTEASE 1(ASP1)interacts with FHY1 in the nucleus under FR and facilitates its deSUMOylation.FHY1 was strongly SUMOylated and its protein level was decreased in the asp1-1 loss-of-function mutant compared with that in the wild type under FR.Consistently,asp1-1 seedlings exhibited a decreased sensitivity to FR,suggesting that ASP1 plays an important role in the maintenance of proper FHY1 levels under FR.Genetic analysis further revealed that ASP1 regulates FR signaling through an FHY1-and phyA-dependent pathway.Interestingly,We found that continuous FR inhibits ASP1 accumulation,perhaps contributing to the desensitization of FR signaling.Taken together,these results indicate that FR-induced SUMOylation and ASP1-dependent deSUMOylation of FHY1 represent a key regulatory mechanism that fine-tunes FR signaling.

Loss of algal Proton Gradient Regulation 5 increases reactive oxygen species scavenging and H2 evolution

Summary We have identified hpm91, a Chlamydomonas mutant lacking Proton Gradient Regulation5 （PGRS） capable of producing hydrogen （H2） for 25 days with more than 3o-fold yield increase compared to wild type. Thus, hpm91 displays a higher capacity of H2 production than a previously characterized pgr5 mutant. Physiological and biochemical characterization of hpm91 reveal that the prolonged H2 production is due to enhanced stability of PSII, which correlates with increased reactive oxygen species （ROS） scavenging capacity during sulfur depriva- tion. This anti-ROS response appears to protect the photosynthetic electron transport chain from photo- oxidative damage and thereby ensures electron supply to the hydrogenase.

Structure of plant photosystem I−light harvesting complex I supercomplex at 2.4Å resolution

Photosystem I(PSI)is one of the two photosystems in photosynthesis,and performs a series of electron transfer reactions leading to the reduction of ferredoxin.In higher plants,PSI is surrounded by four light-harvesting complex I(LHCI)subunits,which harvest and transfer energy efficiently to the PSI core.The crystal structure of PSI-LHCI supercomplex has been analyzed up to 2.6Åresolution,providing much information on the arrangement of proteins and cofactors in this complicated supercomplex.Here we have optimized crystallization conditions,and analyzed the crystal structure of PSI-LHCI at 2.4Åresolution.Our structure showed some shift of the LHCI,especially the Lhca4 subunit,away from the PSI core,suggesting the indirect connection and inefficiency of energy transfer from this Lhca subunit to the PSI core.We identified five new lipids in the structure,most of them are located in the gap region between the Lhca subunits and the PSI core.These lipid molecules may play important roles in binding of the Lhca subunits to the core,as well as in the assembly of the supercomplex.The present results thus provide novel information for the elucidation of the mechanisms for the light-energy harvesting,transfer and assembly of this supercomplex.

Large-scale Proteomic and Phosphoproteomic Analyses of Maize Seedling Leaves During De-etiolation

De-etiolation consists of a series of developmental and physiological changes that a plant undergoes in response to light.During this process light,an important environmental signal,triggers the inhibition of mesocotyl elongation and the production of photosynthetically active chloroplasts,and etiolated leaves transition from the"sink"stage to the"source"stage.De-etiolation has been extensively studied in maize(Zea mays L.).However,little is known about how this transition is regulated.In this study,we described a quantitative proteomic and phosphoproteomic atlas of the de-etiolation process in maize.We identified 16,420 proteins in proteome,among which 14,168 proteins were quantified.In addition,8746 phosphorylation sites within 3110 proteins were identified.From the combined proteomic and phosphoproteomic data,we identified a total of 17,436 proteins.Only 7.0%(998/14,168)of proteins significantly changed in abundance during de-etiolation.In contrast,26.6%of phosphorylated proteins exhibited significant changes in phosphorylation level;these included proteins involved in gene expression and homeostatic pathways and rate-limiting enzymes involved in photosynthetic light and carbon reactions.Based on phosphoproteomic analysis,34.0%(1057/3110)of phosphorylated proteins identified in this study contained more than 2 phosphorylation sites,and 37 proteins contained more than 16 phosphorylation sites,indicating that multi-phosphorylation is ubiquitous during the de-etiolation process.Our results suggest that plants might preferentially regulate the level of posttranslational modifications(PTMs)rather than protein abundance for adapting to changing environments.The study of PTMs could thus better reveal the regulation of de-etiolation.

Cloning, Characterization and Functional Analysis of Two Type 1 Diacylglycerol Acyltransferases (DGAT1s) from Tetraena mongolica

Two cDNAs encoding putative type 1 acyl-CoA： diacylglycerol acyltransferases （DGAT1, EC 2.3.1.20）, were cloned from Tetraena mongolica Maxim., an extreme xerophyte with high oil content in the stems. The 1,488-bp and 1,485-bp of the open reading frame （ORF） of the two cDNAs, designated as TmDGAT1a and TmDGAT1b, were both predicted to encode proteins of 495 and 494 amino acids, respectively. Southern blot analysis revealed that TmDGAT1a and TmDGAT1b both had low copy numbers in the T. mongolica genome. In addition to ubiquitous expression with different intensity in different tissues, including stems, leaves and roots, TmDGAT1a and TmDGAT1b, were found to be strongly induced by high salinity, drought and osmotic stress, resulting in a remarkable increase of triacylglycerol （TAG） accumulation in T. mongolica plantlets. TmDGAT1a and TmDGAT1b activities were confirmed in the yeast H1246 quadruple mutant （DGA1, LRO1, ARE1, ARE2） by restoring DGAT activity of the mutant host to produce TAG. Overexpression of TmDGAT1a and TmDGAT1b in soybean hairy roots as well as in T. mongolica calli both resulted in an increase in oil content （ranging from 37% to 108%）, accompanied by altered fatty acid profiles.