Advances in abscisic acid biosynthesis / 生物工程学报

Abscisic acid, a plant hormone that inhibits growth, is a key factor in balancing plant endogenous hormones and regulating growth and metabolism. Abscisic acid can improve the drought resistance and salt tolerance of crops, reduce fruit browning, reduce the incidence rate of malaria and stimulate insulin secretion, so it has a broad application potential in agriculture and medicine. Compared with traditional plant extraction and chemical synthesis, abscisic acid synthesis by microorganisms is an economic and sustainable route. At present, a lot of progress has been made in the synthesis of abscisic acid by natural microorganisms such as Botrytis cinerea and Cercospora rosea, while the research on the synthesis of abscisic acid by engineered microorganisms is rarely reported. Saccharomyces cerevisiae, Yarrowia lipolytica and Escherichia coli are common hosts for heterologous synthesis of natural products due to their advantages of clear genetic background, easy operation and friendliness for industrial production. Therefore, the heterologous synthesis of abscisic acid by microorganisms is a more promising production method. The author reviews the research on the heterologous synthesis of abscisic acid by microorganisms from five aspects: selection of chassis cells, screening and expression enhancement of key enzymes, regulation of cofactors, enhancement of precursor supply and promotion of abscisic acid efflux. Finally, the future development direction of this field is prospected.

Stomatal behaviour and endogenous phytohormones promotes intrinsic water use efficiency differently in cotton under drought

The coordination between phytohormones regulation, stomatal behaviour (stomatal index and opening/closing) and gas exchange are potent determinants of plant survival under drought stress. However, we found a knowledge gap in the mechanism regulating the fine-tuning of these features during drought. In order to address this we evaluated gas exchange, stomatal behaviour and endogenous phytohormones content in two cotton varieties (LRA-5166 and NBRI-67) differing in drought sensitivity during water deficit conditions. Variety specific differences were recorded in net photosynthesis rate (A), transpiration rate (E) and stomatal conductance (gs) with significantly less decrease in drought tolerant LRA-5166 than drought sensitive NBRI-67. The abscisic acid (ABA) accumulation was significantly increased in LRA-5166 while reduced in NBRI-67 under water deficit, which was accompanied by relatively less reduced 6-benzylaminopurine (6-BAP) level in LRA-5166 than NBRI-67.Thus, improved ABA/6-BAP ratio was observed in both the varieties of cotton. Critically, LRA- 5166 has reduced stomatal index, aperture size and significantly higher A and intrinsic water use efficiency (WUEi), thus higher drought tolerance than NBRI-67. Furthermore, we found that endogenous ABA predominantly maintains the stomatal behaviour and regulates its physiology either by antagonizing 6-BAP or alone to coordinate with water deficit signals. Overall, our findings describe a new insight as to how drought modulates endogenous ABA and 6-BAP homeostasis in cotton leaf and the mechanism of stomatal regulation by ABA and 6-BAP in cotton.

Phytohormone abscisic acid boosts pentobarbital-induced sleep through activation of GABA-A, PPARß and PPARγ receptor signaling / O fito-hormônio ácido abscísico estimula o sono induzido por fenobarbital por meio de ativação da sinalização de receptores GABA-A, PPARß e PPARγ

ABSTRACT Background: Sleep disorders induce anxiety and forgetfulness and change habits. The chemical hypnotic drugs currently used have serious side effects and, therefore, people are drawn towards using natural compounds such as plant-based healing agents. Abscisic acid (ABA) is produced in a variety of mammalian tissues and it is involved in many neurophysiological functions. Objective: To investigate the possible effect of ABA on pentobarbital-induced sleep and its possible signaling through GABA-A and PPAR (γ and β) receptors, in male Wistar rats. Methods: The possible effect of ABA (5 and 10 µg/rat, intracerebroventricularly) on sleep onset latency time and duration was evaluated in a V-maze model of sleep. Pentobarbital sodium (40 mg/kg, intraperitoneally) was injected to induce sleep 30 min after administration of ABA. PPARβ (GSK0660, 80 nM/rat), PPARγ (GW9662, 3 nM/rat) or GABA-A receptor (bicuculline, 6 µg/rat) antagonists were given 15 min before ABA injection. Diazepam (2 mg/kg, intraperitoneally) was used as a positive control group. Results: ABA at 5 µg significantly boosted the pentobarbital-induced subhypnotic effects and promoted induction of sleep onset in a manner comparable to diazepam treatment. Furthermore, pretreatment with bicuculline significantly abolished the ABA effects on sleep parameters, while the amplifying effects of ABA on the induction of sleep onset was not significantly affected by PPARβ or PPARγ antagonists. The sleep prolonging effect of ABA was significantly prevented by both PPAR antagonists. Conclusions: The data showed that ABA boosts pentobarbital-induced sleep and that GABA-A, PPARβ and PPARγ receptors are, at least in part, involved in ABA signaling.

RESUMO Introdução: Os distúrbios do sono induzem a ansiedade e esquecimento e mudam hábitos. Os medicamentos hipnóticos químicos utilizados atualmente têm efeitos colaterais graves e, portanto, as pessoas são atraídas para o uso de compostos naturais, como agentes de cura à base de plantas. O ácido abscísico (ABA) é produzido em uma variedade de tecidos de mamíferos e está envolvido em muitas funções neurofisiológicas. Objetivo: Investigar o possível efeito do ABA no sono induzido por pentobarbital e sua possível sinalização por meio dos receptores GABA-A e PPAR (γ e β), em ratos Wistar machos. Métodos: O possível efeito do ABA (5 e 10 µg/rato, intracerebroventricularmente) no tempo de latência e duração do início do sono foi avaliado em um modelo de labirinto em V de sono. Pentobarbital sódico (40 mg/kg, intraperitonealmente) foi injetado para induzir o sono 30 minutos após a administração de ABA. PPARβ (GSK0660, 80 nM/rato), PPARγ (GW9662, 3 nM/rato) ou antagonistas do receptor GABA-A (bicuculina, 6 µg/rato) foram administrados 15 minutos antes da injeção de ABA. Diazepam (2 mg/kg, intraperitonealmente) foi utilizado como grupo de controle positivo. Resultados: ABA a 5 µg aumentou significativamente os efeitos sub-hipnóticos induzidos por pentobarbital e promoveu a indução do início do sono de forma comparável ao tratamento com diazepam. Além disso, o pré-tratamento com bicuculina aboliu significativamente os efeitos do ABA nos parâmetros do sono, ao passo que os efeitos amplificadores do ABA na indução do início do sono não foram significativamente afetados pelos antagonistas do PPARβ ou PPARγ. O efeito de prolongamento do sono do ABA foi significativamente prevenido por ambos os antagonistas do PPAR. Conclusões: Os dados mostraram que o ABA estimula o sono induzido por pentobarbital e que os receptores GABA-A, PPARβ e PPARγ estão, pelo menos em parte, envolvidos na sinalização ABA.

Ginsenosides in

Ginsenosides are a series of glycosylated triterpenoids which belong to protopanaxadiol (PPD)-, protopanaxatriol (PPT)-, ocotillol (OCT)- and oleanane (OA)-type saponins known as active compounds of

The CYP707A Gene Family in Strawberry (Fragaria × ananassa)

Abstract Abscisic acid (ABA) is a plant hormone that plays several roles in plant development. The de novo synthesis and the reversible inactivation of ABA have been largely described in the literature; however, the degradation of ABA, promoted by the enzymes Abscisic Acid 8'-Hydroxylase, encoded by the CYP707A gene family, is still poorly elucidated. Strawberry (Fragaria x ananassa) has been used as a model to study the ABA-dependent maturation process of non-climacteric fruits, and the ABA-dependent response to abiotic stress. However, the CYP707A genes from this species have not been fully described and characterized. In this perspective, FaCYP707A sequences were identified from strawberry fruit transcriptome and several structural and comparative genomic analyzes were performed. Moreover, the expression of the FaCYP707A sequences identified was investigated in fruits under salt stress and ABA application. Four putative FaCYP707A were identified and the structural analysis confirmed the identity of three of them. The phylogenetic analysis allowed to determine their homologous in other plant species and to predict their evolutionary history; and the expression profile of the FaCYP707As demonstrated that FaCYP707A3 seems to be involved in the response against salt stress in an ABA-dependent manner. Moreover, the interaction network analysis pointed out proteins involved in the ABA metabolism, heavy metal homeostasis and detoxification, and cell wall dissemble. This study characterized for the first time the CYP707A gene family in F. ananassa; this information will guide future studies in order to develop biofortified fruits and stress tolerant plants.

Spinal protein kinase A and phosphorylated extracellular signal-regulated kinase signaling are involved in the antinociceptive effect of phytohormone abscisic acid in rats / A proteína quinase A da medula espinhal e a sinalização da quinase fosforilada regulada por sinal extracelular estão envolvidas no efeito antinociceptivo do ácido fito-hormônio abscísico em ratos

Abstract Objective: The phytohormone abscisic acid (ABA) as a signaling molecule exists in various types of organisms from early multicellular to animal cells and tissues. It has been demonstrated that ABA has an antinociceptive effect in rodents. The present study was designed to assess the possible role of PKA and phosphorylated ERK (p-ERK) on the antinociceptive effects of intrathecal (i.t.) ABA in male Wistar rats. Methods: The animals were cannulated intrathecally and divided into different experimental groups (n=6‒7): Control (no surgery), vehicle (received ABA vehicle), ABA-treated groups (received ABA in doses of 10 or 20 µg/rat), ABA plus H.89 (PKA inhibitor)-treated group which received the inhibitor 15 min prior to the ABA injection. Tail-flick and hot-plate tests were used as acute nociceptive stimulators to assess ABA analgesic effects. p-ERK was evaluated in the dorsal portion of the spinal cord using immunoblotting. Results: Data showed that a microinjection of ABA (10 and 20 µg/rat, i.t.) significantly increased the nociceptive threshold in tail flick and hot plate tests. The application of PKA inhibitor (H.89, 100 nM/rat) significantly inhibited ABA-induced analgesic effects. Expression of p-ERK was significantly decreased in ABA-injected animals, which were not observed in the ABA+H.89-treated group. Conclusions: Overall, i.t. administration of ABA (10 µg/rat) induced analgesia and p-ERK down-expression likely by involving the PKA-dependent mechanism.

Resumo Objetivo: O ácido fito-hormônio abscísico (ABA) existe como molécula sinalizadora em vários tipos de organismos, de multicelulares a células e tecidos animais. Foi demonstrado que o ABA tem efeito antinociceptivo em roedores. O presente estudo foi desenhado para avaliar o possível papel da PKA e da ERK fosforilada (p-ERK) nos efeitos antinociceptivos do ABA intratecal (i.t.) em ratos Wistar machos. Métodos: Os animais foram canulados por via i.t. e divididos em diferentes grupos experimentais (n=6‒7): controle (sem cirurgia), veículo (veículo ABA recebido), grupos tratados com ABA (recebeu ABA em doses de 10 ou 20 µg/rato), grupo tratado com ABA mais H.89 (inibidor de PKA) que recebeu o inibidor 15 minutos antes da injeção de ABA. Os testes de movimento da cauda e placa quente foram utilizados como estimuladores nociceptivos agudos para avaliar os efeitos analgésicos da ABA. A p-ERK foi avaliada na porção dorsal da medula espinhal por imunotransferência. Resultados: A microinjeção de ABA (10 e 20 µg/rato, i.t.) aumentou significativamente o limiar nociceptivo nos testes de movimento da cauda e placa quente. A aplicação de inibidor de PKA (H.89, 100 nM/rato) inibiu significativamente os efeitos analgésicos induzidos por ABA. A expressão de p-ERK diminuiu significativamente em animais injetados com ABA que não foram observados no grupo tratado com ABA+H.89. Conclusões: No geral, a administração i.t. de ABA (10 µg/rato) induziu a analgesia e expressão negativa de p-ERK provavelmente envolvendo mecanismo dependente de PKA.

Drying temperature affects rice seed vigor via gibberellin, abscisic acid, and antioxidant enzyme metabolism / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Seed vigor is a key factor affecting seed quality. The mechanical drying process exerts a significant influence on rice seed vigor. The initial moisture content (IMC) and drying temperature are considered the main factors affecting rice seed vigor through mechanical drying. This study aimed to determine the optimum drying temperature for rice seeds according to the IMC, and elucidate the mechanisms mediating the effects of drying temperature and IMC on seed vigor. Rice seeds with three different IMCs (20%, 25%, and 30%) were dried to the target moisture content (14%) at four different drying temperatures. The results showed that the drying temperature and IMC had significant effects on the drying performance and vigor of the rice seeds. The upper limits of drying temperature for rice seeds with 20%, 25%, and 30% IMCs were 45, 42, and 38 °C, respectively. The drying rate and seed temperature increased significantly with increasing drying temperature. The drying temperature, drying rate, and seed temperature showed extremely significant negative correlations with germination energy (GE), germination rate, germination index (GI), and vigor index (VI). A high IMC and drying temperature probably induced a massive accumulation of hydrogen peroxide (H2O2) and superoxide anions in the seeds, enhanced superoxide dismutase (SOD) and catalase (CAT) activity, and increased the abscisic acid (ABA) content. In the early stage of seed germination, the IMC and drying temperature regulated seed germination through the metabolism of H2O2, gibberellin acid (GA), ABA, and α-amylase. These results indicate that the metabolism of reactive oxygen species (ROS), antioxidant enzymes, GA, ABA, and α-amylase might be involved in the mediation of the effects of drying temperature on seed vigor. The results of this study provide a theoretical basis and technical guidance for the mechanical drying of rice seeds.

Effect of inoculation time of arbuscular mycorrhizal fungi on endogenous hormone content in Paris polyphylla var. yunnanensis seedlings / 中草药

Objective: To study the effect of the inoculation time of arbuscular mycorrhizal (AM) fungi on endogenous hormone content in Paris polyphylla var. yunnanensis seedlings. Methods: The indoor pot test was applied. The seeds, one-year-old seedlings, and two-year-old seedlings of P. polyphylla var. yunnanensis were inoculated by different mixed AM fungi and cultivated in the sterilized soil matrix respectively. The contents of endogenous hormone zeatin riboside (ZR), gibberellin (GA), indole acetic acid (IAA) and abscisic acid (ABA) were determined by HPLC. Results: The results showed that the endogenous hormone (ZR, GA, IAA and ABA) contents in rhizome and fibrous roots of P. polyphylla var. yunnanensis from different regions or different time inoculated by mixed AM fungi were various. As a whole, the contents of endogenous hormone ZR and GA increased obviously in the rhizome and fibrous roots of the wild and cultivated P. polyphylla var. yunnanensis compared with the control group (CK), while the content of ABA reduced. The IAA/ABA value, GA/ABA value and ZR/ABA value increased obviously in the rhizome and fibrous roots of P. polyphylla var. yunnanensis. Conclusion: The one-year-old of P. polyphylla var. yunnanensis inoculated with S2 and S6 mixed AM fungi showed the best comprehensive effect for promoting growth of the rhizome and fibrous roots of P. polyphylla var. yunnanensis seedlings.

Genome-wide identification of abscisic acid (ABA) receptor pyrabactin resistance 1-like protein (PYL) family members and expression analysis of PYL genes in response to different concentrations of ABA stress in Glycyrrhiza uralensis / 中国天然药物

As abscisic acid (ABA) receptor, the pyrabactin resistance 1-like (PYR/PYL) protein (named PYL for simplicity) plays an important part to unveil the signal transduction of ABA and its regulatory mechanisms. Glycyrrhiza uralensis, a drought-tolerant medicinal plant, is a good model for the mechanism analysis of ABA response and active compound biosynthesis. However, knowledge about PYL family in G. uralensis remains largely unknown. Here, 10 PYLs were identified in G. uralensis genome. Characterization analysis indicated that PYLs in G. uralensis (GuPYLs) are relatively conserved. Phylogenetic analysis showed that GuPYL1-3 belongs to subfamily I, GuPYL4-6 and GuPYL10 belong to subfamily II and GuPYL7-9 belongs to subfamily III. In addition, transcriptome data presented various expression levels of GuPYLs under different exogenous ABA stresses. The expression pattern of GuPYLs was verified by Quantitative real-time polymerase chain reaction (qRT-PCR). The study proved that GuPYL4, GuPYL5, GuPYL8 and GuPYL9 genes are significantly up-regulated by ABA stress and the response process is dynamic. This study paves the way for elucidating the regulation mechanism of ABA signal to secondary metabolites and improving the cultivation and quality of G. uralensis using agricultural strategies.

Genome-wide characterization of the abscisic acid-, stress- and ripening-induced (ASR) gene family in wheat (Triticum aestivum L)

BACKGROUND: Abscisic acid-, stress-, and ripening-induced (ASR) genes are a class of plant specific transcription factors (TFs), which play important roles in plant development, growth and abiotic stress responses. The wheat ASRs have not been described in genome-wide yet. METHODS: We predicted the transmembrane regions and subcellular localization using the TMHMM server, and Plant-mPLoc server and CELLO v2.5, respectively. Then the phylogeny tree was built by MEGA7. The exon-intron structures, conserved motifs and TFs binding sites were analyzed by GSDS, MEME program and PlantRegMap, respectively. RESULTS: In wheat, 33ASR genes were identified through a genome-wide survey and classified into six groups. Phylogenetic analyses revealed that the TaASR proteins in the same group tightly clustered together, compared with those from other species. Duplication analysis indicated that the TaASR gene family has expanded mainly through tandem and segmental duplication events. Similar gene structures and conserved protein motifs of TaASRs in wheat were identified in the same groups. ASR genes contained various TF binding cites associated with the stress responses in the promoter region. Gene expression was generally associated with the expected group-specific expression pattern in five tissues, including grain, leaf, root, spike and stem, indicating the broad conservation of ASR genes function during wheat evolution. The qRT-PCR analysis revealed that several ASRs were up-regulated in response to NaCl and PEG stress. CONCLUSION: We identified ASR genes in wheat and found that gene duplication events are the main driving force for ASR gene evolution in wheat. The expression of wheat ASR genes was modulated in responses to multiple abiotic stresses, including drought/osmotic and salt stress. The results provided important information for further identifications of the functions of wheat ASR genes and candidate genes for high abiotic stress tolerant wheat breeding.

Effects of methyle jasmonate on active components, anti-oxidant enzyme activities and endogenous hormone content in Blumea balsamifera / 中草药

Objective To study the regulation among the content of L-borneol and four endogenous hormones and the activity of three anti-oxidant enzymes in Blumea balsamifera leaves located at different leaf positions and the concentration of inducer and the sampling time. Methods Methyle Jasmonate (MeJA) of 0.01 mmol/L, 0.10 mmol/L, 1.00 mmol/L, and 10.00 mmol/L was chosen for exogenous inducer in this experiment. The leaves of B. balsamifera located at different leaf positions (tender leaves, mature leaves, aged leaves) were experimental materials. The active content of L-borneol, the content of four endogenous hormones of auxin (IAA), abscisic acid (ABA), gibberellic acid (GA3), and zeatin (ZT), and the activity of three antioxidant enzymes of peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD) were detection indexes. Results The results showed that the effect of 1.00 mmol/L MeJA on the accumulation of L-borneol was good. The changes of anti-oxidant enzymes induced by different concentrations of MeJA were complex. For the content of POD, except that the B. balsamifera leaves treated with 10.00 mmol/L MeJA were lower than that in the control, POD were significantly higher than those of the control (P < 0.05) at 72 h in other conditions. Under the induction of 10.00 mmol/L MeJA, the CAT content of the B. balsamifera leaves at three leaf positions was highest at 24 h, and the activity of CAT was decreased rapidly over time. Under the MeJA treatments of other concentrations, the activities of CAT in young leaves and old leaves were significantly lower than those in the control at 72 h, but higher than those in the control at 72 h except for the treatment of 0.1 mmol/L MeJA in mature leaves. The content of SOD in the three leaf positions was lower than the control except that the B. balsamifera leaves treated with 1 mmol/L MeJA was significantly higher than that of the control after 48 h. The rest of the concentration of superoxide dismutase were lower than the control. Low concentration of MeJA (≤ 0.10 mmol/L) could promote the accumulation of IAA, GA3, and ZT in leaves of B. balsamifera, whereas the high concentration of MeJA (≥ 10.00 mmol/L) could promote the accumulation of ABA. Conclusion Under the induction of exogenous MeJA (1.00 mmol/L), B. balsamifera can promote the accumulation of active ingredients, providing a theoretical basis for its cultivation and production.

Molecular cloning and characterisation of scavenger receptor class B in pearl oyster Pinctada fuctada martensii

Background: Molluscs can accumulate carotenoids in their body tissues by predominantly feeding on aquatic plant sources. Carotenoid transport and absorption are determined by the regulation of various proteins such as Scavenger receptor class B(SR-BI). We report the identification and characterisation of pearl oyster Pinctada fuctada martensii SR-BI (PmSR-BI). The correlation between total carotenoid content (TCC) and gene expression was also estimated. Results: The full-length cDNA of PmSR-BI was 1828 bp, including an open-reading frame encoding of 1518 bp with a pI value of 5.83. PmSR-BI protein contains a hydrophobic CD36 domain and four centrally clustered cysteine residues for the arrangement of disulphide bridges. The deduced amino acid sequence had an identity of 30% to 60% with the SR-B of other organisms. Reverse transcription polymerase chain reaction analysis showed that mRNA transcripts were expressed in multiple tissues of adult pearl oyster. A higher expression of PmSR-BI gene was observed in the hepatopancreas than in the adductor muscle, gill and mantle. The TCC and gene expression of PmSR-BI were significantly correlated (P b 0.05), with a correlation coefficient of 0.978. Conclusions: The results suggested that PmSR-BI is involved in the absorption of carotenoids in the pearl oyster P. fuctada martensii.

Study on the Effects of Exogenous Abscisic Acid on Salt-alkali Tolerance of Scrophularia ningpoensis Seed-lings / 中国药房

OBJECTIVE:To study the effects of exogenous abscisic acid(ABA)on salt-alkali tolerance of Scrophularia ning-poensis seedlings,and to provide theoretic evidence for cultivating S. ningpoensis in salt-alkali soil. METHODS:50 S. ningpoensis seedlings were divided into control group,salt-alkali group(75 mmol/L),salt-alkali(75 mmol/L)+ABA low-concentration,medi-um-concentration and high-concentration groups(10,50,100 μmol/L),with 10 plants in each group. 20 days after transplanting, the plants were sprayed with drugs every 4 days. Growth indexes of the plants(length of stem,fresh weight,dry weight,survival rate),physiological indexes [the contents of chlorophyll,soluble sugar (SS),soluble protein (SP) and free proline (Pro)],the contents of MDA and H2O2,the activities of antioxidase [the activities of SOD,POD,CAT,GR] and the contents of Na+ and K+in stem and root were determined in each group 2 weeks later. RESULTS:Compared with control group,stem height and survival rate of S. ningpoensis seedlings,SP,the contents of Na+ and K+ in the stem,the contents of Na+,CAT and GR in the roots were all decreased significantly in salt-alkali group;while chlorophyll,Pro,MDA and H2O2 contents,the content of K+ in the roots and the activities of SOD and POD were all increased significantly(P<0.05 or P<0.01). Compared with salt-alkali group,stem height of S. ningpoensis seedlings,fresh weight and chlorophyll content were increased significantly in salt-alkali+ABA medium-concentra-tion group,while MDA and the content of Na+ in the stem were decreased significantly;dry weight,the contents of SS and SP, the activities of SOD and CAT were increased significantly in salt-alkali+ABA low-concentration and medium-concentration groups, while the SS content was increased in salt-alkali+ABA high-concentration group;stem height and dry weight were decreased signifi-cantly in salt-alkali+ABA high-concentration group;Pro content of salt-alkali+ABA low-concentration and high-concentration groups were decreased significantly;H2O2,Na+ content in the roots were decreased significantly in salt-alkali+ABA low-concentra-tion,medium-concentration and high-concentration groups;while GR activity,K+ content in the stem and roots were increased sig-nificantly;POD activity were decreased significantly in salt-alkali+ABA medium-concentration and high-concentration groups. CON-CLUSIONS:The addition of a certain concentration of exogenous ABA can effectively increase salt-alkali tolerance of S. ningpoen-sis seedlings and strengthen the ability of the plant adapting to salt-alkali environment.

Expression analysis of bZIP transcription factor encoding genes in response to water deficit stress in rice.

In plants, basic region/leucine zipper motif (bZIP) transcription factors regulate several developmental processes and activate genes in response to biotic and abiotic stresses. Role of stress responsive bZIP transcription factors was studied in paddy in relation to different stages of development and water deficit stress (WDS) in a drought tolerant cultivar N22 and susceptible IR 64. Further, relative water content (RWC), membrane stability index (MSI) and abscisic acid (ABA) content were measured as indices of WDS at different stages of development and levels of stress. Expression of stress responsive bZIP transcription factors was directly correlated to developmental stage and WDS and indirectly to RWC, MSI and ABA content.

Germination and dessication of Hancornia speciosa Gomes seeds / Germinação e secagem de sementes de Hancornia speciosa Gomes

The aim of this work was describe the germination and evaluate the desiccation and reduction in desiccation sensitivity of Hancornia speciosa Gomes seeds. Initially, we evaluated the germination characteristics and morphophysiological aspects of seedlings. The seeds in the first experiment were subjected to fast desiccation (activated silica gel) and slow desiccation (laboratory conditions) until the water content reached 40%, 30%, 20%, and 15% ± 2%. To reduce the desiccation sensitivity, in the second experiment, the seeds were soaked in polyethylene glycol (PEG) at potentials of -0.1 and - 0.3 MPa for 120 h, with or without abscisic acid (ABA) (10-4µM), and subsequently subjected to fast desiccation until a water content of 15% was reached, based on the results from the first experiment. The seed vigor in both experiments was evaluated by the primary root protrusion tests, percentage of normal seedlings, germination speed index, length and mass (shoot, underground, and total). Seedlings of H. speciosa feature a stem-like xylopodium structure. The seeds were tolerant to water reduction up to 15% by fast desiccation and 30% by slow desiccation. Moreover, priming was not efficient in reducing the desiccation sensitivity of H. speciosa seeds.

Objetivou-se neste trabalho descrever a germinação e avaliar a secagem e a redução da sensibilidade à dessecação em sementes de Hancornia speciosa Gomes. Inicialmente, foi realizada a descrição das características de germinação e aspectos morfofisiológicos das plântulas. Para primeiro experimento, as sementes foram submetidas à secagem rápida (sílica gel ativada) e à secagem lenta (condições de ambiente de laboratório) até atingirem os teores de água de 40, 30, 20 e 15 ± 2%. Na tentativa da redução da sensibilidade à dessecação em um segundo experimento, as sementes foram embebidas em polietileno glicol (PEG) nos potenciais de -0,1 e -0,3 MPa por 120 horas associados ou não ao ácido abscísico (ABA) (10-4M) e posteriormente submetidas a secagem rápida no teor de água de 15%, de acordo com os resultados do primeiro experimento. O potencial fisiológico das sementes, em ambos os experimentos, foi avaliado por meio dos testes de protrusão da raiz primária, porcentagem de plântulas normais, índice de velocidade de germinação, comprimento e massa seca de plântulas (parte aérea, sistema subterrâneo e total). As plântulas de H. speciosa apresentam xilopódio de estrutura caulinar. As sementes toleram a redução do teor de água até 15% na secagem rápida e de 30% para secagem lenta. O condicionamento osmótico não foi eficiente para reduzir a sensibilidade à dessecação de sementes de H. speciosa.

Cloning and expression analysis of WRKY5 gene in Dendrobium officinale / 中草药

Objective: In order to isolate and analysize the bioinformatics and expression pattern of DoWRKY5 gene from Dendrobium officinale. Methods: A WRKY gene was first obtained by transcriptome sequencing and reverse transcription-polymerase chain reaction (RT-PCR) from D. officinale and analyzed by bioinformatics tools. The tissue expression pattern and the low temperature stress, abscisic acid (ABA) stress, and sucrose stress responses were analyzed by qRT-PCR. Results: The cDNA sequence of DoWRKY5 gene was isolated, which was 1 336 bp in length, with an open reading frame (ORF) of 834 bp and an encoded polypeptide of 277 amino acid. The amino acid sequence contained a conserved WRKY domains and a zinc finger structures (C2H2), belonging to Group II of WRKY family. Expression analysis by qRT-PCR showed that DoWRKY5 was expressed in the roots, stems, and leaves of D. officinale, and the most abundant in leaves. The amount of DoWRKY5 expression were significantly increased under low temperature of 4℃ and different time. Moreover, the expression of DoWRKY5 could be induced by ABA and source. Conclusion: DoWRKY5 may be an important transcription factor to response cold stress and other abiotic stresses in D. officinale, which provides a foundation for further study of cold tolerance mechanism and cold-resistant breeding of D. officinale.

Research on chemical constituents from Re-Du-Ning Injection (III) / 中草药

Objective: To study the antiviral constituents from the active fraction of Re-Du-Ning (RDN) Injection. Methods: In this study, the active fraction of RDN Injection was screened by the mice model loaded with restraint stress infected with influenza virus. The chemical constituents were isolated by chromatography on silica gel, ODS, Sephadex LH-20 & Toyopearl HW-40 columns, and reverse phase MPLC & HPLC repeatedly. Their structures were identified by spectral data and physicochemical property. Results: The 95% ethanol eluate of RDN Injection on the macroporous adsorption resin column was proved to be the antivirus active fraction of RDN Injection. Fourteen compounds were isolated and identified as (2E,6S)-8-[α-L-arabinopyranosyl-(1″-6')-β-D-glucopyranosyloxy]- 2,6-dimethylct-2-eno-1,2″-lactone (1), lyoniresinol (2), 5'-methoxyisolariciresinol (3), ent-isolariciresinol (4), (7R,8R)-4,7,9,9'- tetrahydroxy-3,3'-dimethoxy-8-O-4'-neolignan (5), (7S,8R)-4,7,9,9'-tetrahydroxy-3,3'-dimethoxy-8-O-4'-neolignan (6), ceplignan (7), 5'-methoxyceplignan (8), (-)-dihydrodehydrodiconiferyl alcohol (9), (7S,8R)-3,3',5-trimethoxy-4',7-epoxy-8,5'-neolignan-4,9,9'-triol (10), (2-cis, 4-trans)-abscisic acid (11), (2-trans, 4-trans)-abscisic acid (12), (1S,3R,4R,5S,7R,9R)-decane-6-carboxylic acid (13), and (1S,3R,4S,5S,7R,9R)-decane-6-carboxylic acid (14); Among them, compound 1 exhibited the antivirus activity against Dengue virus. Conclusion: Compound 8 is a new compound and the other isolated compounds are reported from RDN Injection for the first time, and compound 1 shows the anti-virus activity against Dengue virus.

Cloning and bioinformatics analysis of abscisic acid 8'-hydroxylase from Pseudostellariae Radix / 中国中药杂志

Abscisic acid 8'-hydroxylase was one of key enzymes genes in the metabolism of abscisic acid (ABA). Seven menbers of abscisic acid 8'-hydroxylase were identified from Pseudostellaria heterophylla transcriptome sequencing results by using sequence homology. The expression profiles of these genes were analyzed by transcriptome data. The coding sequence of ABA8ox1 was cloned and analyzed by informational technology. The full-length cDNA of ABA8ox1 was 1 401 bp,with 480 encoded amino acids. The predicated isoelectric point (pI) and relative molecular mass (MW) were 8.55 and 53 kDa,respectively. Transmembrane structure analysis showed that there were 21 amino acids in-side and 445 amino acids out-side. High level of transcripts can detect in bark of root and fibrous root. Multi-alignment and phylogenetic analysis both show that ABA8ox1 had a high similarity with the CYP707As from other plants,especially with AtCYP707A1 and AtCYP707A3 in Arabidopsis thaliana. These results lay a foundation for molecular mechanism of tuberous root expanding and response to adversity stress.

Chemical constituents from roots of Kadsura longipedunculata / 中草药

Objective: To study the chemical constituents from the roots of Kadsura longipedunculata. Methods: The constituents were isolated and purified by various chromatographic methods, and the structures were elucidated by spectroscopic analysis. Results: Sixteen compounds were isolated from the roots of K. longipedunculata and the structures were identified as pinobatol (1), leptolepisol B (2), 7S,8R-erythro-4,7,9,9'-tetrahydroxy-3,3'-dimethoxy-8-O-4'-neolignan (3), 2,3-bis-(α-hydroxy-4-hydroxy-3-methoxybenzyl)-butane-1,4-diol (4), (7'S,8R,8'S)-4,4',9-trihydroxy-3,3',5-trimethoxy-9'-O-β-D-xylopyranosyl-2,7'-cyclo-lignan (5), aviculin (6), ent-isolariciresinol (7), lawsorosemarinol (8), (+)-anwulignan (9), isolariciresinol-2α-O-β-D-xyloside (10), procyanidin B3 (11), prodelphinidin B3 (12), (-)-gallocatechin (13), (+)-catechin (14), abscisic acid-β-D-glucopyranosyl ester (15), and (-)-oleuropeic acid 8-O-β-D-glucopyranoside (16). Conclusion: Compounds 1-8, 11-13, 15, and 16 are isolated from the plants of Kadsura Kaempf. ex Juss. for the first time.

Molecular cloning and expression analysis of a late embryogenesis abundant protein gene (SmLEA2) from Salvia miltiorrhiza / 中草药

Objective: To clone and characterize a late embryogenesis abundant protein SmLEA2 with its promoter region from Salvia miltiorrhiza, and to predict its probable function. Methods: SmLEA2 was cloned by PCR and RT-PCR from genomic DNA and cDNA. Protein structure and phylogenetic relationships were carried out by bioinformatic analysis. Gene expression in different organs and different development periods was detected by qPCR. Gene expression was also detected under different treatments. Results: By analyzing the cDNA library for S. miltiorrhiza with BLAST program, one of these sequences showed a high homology with late embryogenesis abundant (LEA) protein and was named as SmLEA2 (GenBank: HQ676610). We obtained 1 961 bp gene sequences of SmLEA2, which contained an intron and a single opening reading frame (ORF) of 960 bp encoding 319 amino acid peptides. Bioinformatic analysis showed that the putative SmLEA2 protein was a hydrophilic protein without signal peptides and transmembrane domains. The SmLEA2 protein was predicted with a molecular weight of 35 340 and a theoretical isoelectric point of 4.77. SmLEA2 was expressed in the roots, stems, and leaves of S. miltiorrhiza, and the most abundant in the stems. With the development of the flowers and seeds, its expression increased gradually. Expression of SmLEA2 could be induced by methyl jasmonate (MeJA) and abscisic acid (ABA). Conclusion: Thus, we speculate that SmLEA2 may be involved in seed development and plant defenses.