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Purple-grained wheat (Triticum aestivum L.) is an important germplasm source in crop breeding. Anthocyanin biosynthesis in the pericarps of purple-grained wheat is largely light-dependent; however, the regulatory mechanisms underlying light-induced anthocyanin accumulation in the wheat pericarp remain unknown. Here we determined that anthocyanins rapidly accumulate in the pericarps of the purple-grained wheat cultivar Heixiaomai 76 (H76) at 16 days after pollination under light treatment. Using transcriptome sequencing, differential gene expression analysis, and phylogenetic analysis, we identified two key genes involved in light signaling in wheat: ELONGATED HYPOCOTYL 5-7A (TaHY5-7A) and B-BOX-3B (TaBBX-3B). TaHY5-7A and TaBBX-3B were highly expressed in purple-grained wheat pericarps. The heterologous expression of TaHY5-7A partially restored the phenotype of the Arabidopsis (Arabidopsis thaliana) hy5 mutant, resulting in increased anthocyanin accumulation and a shortened hypocotyl. The heterologous expression of TaBBX-3B in wild-type Arabidopsis had similar effects. TaHY5-7A and TaBBX-3B were nucleus-localized, consistent with a function in transcription regulation. However, TaHY5-7A, which lacks a transactivation domain, was not sufficient to activate the expression of PURPLE PERICARP-MYB 1 (TaPpm1), the key anthocyanin biosynthesis regulator in purple pericarps of wheat. TaHY5-7A physically interacted with TaBBX-3B in yeast two-hybrid and bimolecular fluorescence complementation assays. Additionally, TaHY5-7A, together with TaBBX-3B, greatly enhanced the promoter activity of TaPpm1 in a dual luciferase assay. Overall, our results suggest that TaHY5-7A and TaBBX-3B collaboratively activate TaPpm1 expression to promote light-induced anthocyanin biosynthesis in purple-pericarp wheat. [ABSTRACT FROM AUTHOR]

Main conclusion: OsFAR1 encodes a fatty acyl-CoA reductase involved in biosynthesis of primary alcohols and plays an important role in drought stress response in rice. Cuticular waxes cover the outermost surface of terrestrial plants and contribute to inhibiting nonstomatal water loss and improving plant drought resistance. Primary alcohols are the most abundant components in the leaf cuticular waxes of rice (Oryza sativa), but the biosynthesis and regulation of primary alcohol remain largely unknown in rice. Here, we identified and characterized an OsFAR1 gene belonging to the fatty acyl-CoA reductases (FARs) via a homology-based approach in rice. OsFAR1 was activated by abiotic stresses and abscisic acid, resulting in increased production of primary alcohol in rice. Heterologous expression of OsFAR1 enhanced the amounts of C22:0 and C24:0 primary alcohols in yeast (Saccharomyces cerevisiae) and C24:0 to C32:0 primary alcohols in Arabidopsis. Similarly, OsFAR1 overexpression significantly increased the content of C24:0 to C30:0 primary alcohols on rice leaves. Finally, OsFAR1 overexpression lines exhibited reduced cuticle permeability and enhanced drought tolerance in rice and Arabidopsis. Taken together, our results demonstrate that OsFAR1 is involved in rice primary alcohol biosynthesis and plays an important role in responding to drought and other environmental stresses. [ABSTRACT FROM AUTHOR]

Fritillaria is a perennial herb with medicinal properties. There are 158 Fritillaria species worldwide, 33 of which have reported therapeutic efficacy. Alkaloids are the principal constituents in Fritillaria. Fritillaria species growing at 2700–4000 m are the sources of extract namely Chuan Beimu (the Pharmacopoeia of the People's Republic of China, 2020 Edition), with low biomass, mainly containing more 5α-cevanine isosteroidal alkaloids with cis-configuration. In contrast, species growing below 1500 m are usually taller than 50 cm, and they mainly contain more trans-configuration isosteroidal alkaloids. There are two schemes of the biosynthetic pathways of steroidal alkaloids with different frameworks and catalytic reactions and combined high-throughput omics data. Based on the distributed elevations, Fritillaria species were divided into three major categories, which met classification features based on phylogenetic analysis or morphological features. Artificial or in vitro cultivations are effective strategies for balancing economical requirements and ecological protection. Fritillaria species growing at lower altitudes can be cultivated by bulb reproduction, but species growing at higher altitudes still rely mainly on gathering a large number of wild resources. Integration of asexual tissue culture and bulb reproduction with sexual artificial or imitated wild cultivation may create a very promising and effective way to maintain sustainable industrial development of Fritillaria. [ABSTRACT FROM AUTHOR]

Anthocyanins cause purple, brown or red colors in various tissues of rice plants, but the specific determinant factors and regulatory systems for anthocyanin biosynthesis in almost all tissues remain largely unknown. In the present study, we mapped and isolated two complementary genes, OsC1 encoding a R2R3-MYB transcriptional factor and OsDFR encoding a dihydroflavonol 4-reductase, which are responsible for the purple coloration of apiculi and stigmas in indica cultivar Xieqingzao by the map-based cloning strategy. We also identified two tissue-specific pigmentation genes, OsPa for apiculi and OsPs for stigmas, by phylogenetic analysis of all anthocyanin biosynthesis-associated bHLH transcriptional factors in maize and rice, CRISPR/Cas9 knockout and transcriptional expression analysis. The OsC1, OsPa and OsPs proteins are all localized in the nucleus while the OsDFR protein is localized in the nucleus and cytoplasm, and the OsC1 and OsDFR genes are preferentially strongly expressed in both purple-colored tissues while the OsPa and OsPs genes are preferentially strongly expressed in apiculi and stigmas, respectively. OsC1 specifically interacts with OsPa or OsPs to activate OsDFR and other anthocyanin biosynthesis genes, resulting in purple-colored apiculi or stigmas. OsC1 itself does not produce color but can produce brown apiculi when functioning together with OsPa. Loss of function of OsDFR alone leads to brown apiculi and straw-white stigmas. Genotyping and phenotyping of a panel of 176 rice accessions revealed diverse genotypic combinations of OsC1, OsDFR, OsPa and OsPs that enable accurate prediction of their apiculus and stigma pigmentation phenotypes, thus validating the general applicability of the OsC1-OsDFR-OsPa and OsC1-OsDFR-OsPs models to natural populations. Our findings disclosed the biological functions of OsC1, OsPa and OsPs, and shed light on the specific regulatory systems of anthocyanin biosynthesis in apiculi and stigmas, a further step in understanding the regulatory network of anthocyanin biosynthesis in rice. [ABSTRACT FROM AUTHOR]

Cuticular waxes are the covering of the outer layer of the plant, consist of hydrocarbon appears like whitish film or bloom in plant organs. They play a vital role like a safeguard from different stress condition in the plant. Since environmental factors are active regulators of cuticular wax biosynthesis, composition, quantity, and deposition, it is evident that cuticular wax is associated with plant stress responses. The diversity of cuticular wax compositions is a proof of the wealth of genes associated in plant wax production. Moreover, a number of wax genes were distinguished in plant/crops at abiotic stress conditions but, regulation of control of those wax genes has not been studied very well in major crop plants at abiotic conditions. A very few transcriptions factors were identified to regulate the expression level of wax genes of cuticular wax biosynthesis at abiotic stress condition. However, further study is needed to identify more candidate transcriptional regulation factors to cuticular wax production in different crop plants in diverse abiotic environments. Therefore, regulation of cuticular wax production under diverse abiotic stresses and the role of transcription factors into the plant cuticular wax accumulation will be helpful to engineer crop plants and improve transgenic crops for stress tolerance. In this review, we focused on a new perspective on transcriptional factors to regulate functional genes of cuticular wax biosynthesis in plants at abiotic stresses. [ABSTRACT FROM AUTHOR]

Summary: Alkylresorcinols are bioactive compounds produced in diverse plant species, with chemical structures combining an aliphatic hydrocarbon chain and an aromatic ring with characteristic hydroxyl substituents. Here, we aimed to isolate and characterize the enzyme that forms the alkylresorcinols accumulating in the cuticular wax on the surface of all above‐ground organs of rye. Based on sequence homology with other type‐III polyketide synthases, a candidate alkylresorcinol synthase was cloned. Yeast heterologous expression showed that the enzyme, ScARS, is highly specific for the formation of the aromatic resorcinol ring structure, through aldol condensation analogous to stilbene synthases. The enzyme accepts long‐chain and very‐long‐chain acyl‐CoA starter substrates, preferring saturated over unsaturated chains. It typically carries out three rounds of condensation with malonyl‐CoA prior to cyclization, with only very minor activity for a fourth round of malonyl‐CoA condensation and cyclization to 5‐(2′‐oxo)‐alkylresorcinols or 5‐(2′‐hydroxy)‐alkylresorcinols. Like other enzymes involved in cuticle formation, ScARS is localized to the endoplasmic reticulum. ScARS expression patterns were found correlated with alkylresorcinol accumulation during leaf development and across different rye organs. Overall, our results thus suggest that ScARS synthesizes the cuticular alkylresorcinols found on diverse rye organ surfaces. [ABSTRACT FROM AUTHOR]

Cuticular wax accumulation and composition affects drought resistance in plants. Brachypodium distachyon plants subjected to water deficit and polyethylene glycol treatments resulted in a significant increase in total wax load, in which very-long-chain (VLC) alkanes were more sensitive to these treatments than other wax compounds, implying that VLC alkanes biosynthesis plays a more important role in drought resistance in B. distachyon. ECERIFERUM1 (CER1) has been reported to encode a core enzyme involved in VLC alkanes biosynthesis in Arabidopsis (Arabidopsis thaliana), but few corresponding genes are investigated in B. distachyon. Here, we identified eight CER1 homologous genes in B. distachyon , namely BdCER1-1 to BdCER1-8 , and then analyzed their sequences feature, expression patterns, stress induction, and biochemical activities. These genes had similar protein structure to other reported CER1 and CER1 -like genes, but displayed closer phylogenetic relationship to the rice OsGL1 genes. They were further found to exhibit various tissue expression patterns after being induced by abiotic stresses. Among them, BdCER1-8 gene showed extremely high expression in leaves. Heterologous introduction of BdCER1-8 into the Arabidopsis cer1 mutant rescued VLC alkanes biosynthesis. These results indicate that BdCER1 genes are likely to be involved in VLC alkanes biosynthesis of B. distachyon. Taken together, BdCER1-8 seems to play an explicit and predominant role in VLC alkanes biosynthesis in leaf. Our work provides important clues for further characterizing function of CER1 homologous genes in B. distachyon and also an option to improve drought resistance of cereal crops. [ABSTRACT FROM AUTHOR]

To protect above‐ground plant organs from excessive water loss, their surfaces are coated by waxes. The genes involved in wax formation have been investigated in detail in Arabidopsis but scarcely in crop species. Here, we aimed to isolate and characterize a CER1 enzyme responsible for formation of the very long‐chain alkanes present in high concentrations especially during late stages of wheat development. On the basis of comparative wax and transcriptome analyses of various wheat organs, we selected TaCER1‐1A as a primary candidate and demonstrated that it was located to the endoplasmic reticulum, the subcellular compartment for wax biosynthesis. A wheat nullisomic‐tetrasomic substitution line lacking TaCER1‐1A had significantly reduced amounts of C33 alkane, whereas rice plants overexpressing TaCER1‐1A showed substantial increases of C25–C33 alkanes relative to wild type control. Similarly, heterologous expression of TaCER1‐1A in Arabidopsis wild type and the cer1 mutant resulted in increased levels of unbranched alkanes, iso‐branched alkanes and alkenes. Finally, the expression of TaCER1‐1A was found activated by abiotic stresses and abscisic acid treatment, resulting in increased production of alkanes in wheat. Taken together, our results demonstrate that TaCER1‐1A plays an important role in wheat wax alkane biosynthesis and involved in responding to drought and other environmental stresses. In this paper, the function of TaCER1‐1A involved in wheat alkane biosynthesis was tested using gain‐of‐function (transgenic plants) and loss‐of‐function plants (gene deletion wheat line), and the role of alkanes in drought resistance was assessed. [ABSTRACT FROM AUTHOR]

HMG-CoA reductase inhibitors were widely used as lipid-lowing agents through effectively blocking the rate-limiting step of cholesterol biosynthesis. 8 analogs of Rosuvastatin were firstly prepared with different distance and functional group between the O5-hydroxyl group and terminal COOH group in the hydrophilic side-chain. In primary and secondary screening of the inhibitory activities against human HMG-CoA reductase, gem-difluoromethylenated derivatives exhibited more than 50% inhibition rate. Then 4 compounds with gem-difluoro group were further synthesized and evaluated in vitro, three compounds among them exhibited low single digital nmol/L IC50 values against HMG-CoA reductase. Molecular docking also well explained the observed special contribution of the gem-difluoro group. [ABSTRACT FROM AUTHOR]

TaFAR5, a fatty acyl-coenzyme A reductase, catalyses the synthesis of primary alcohols in wheat cuticle and is linked to response to abiotic stress in an ABA-dependent manner.A waxy cuticle that serves as a protective barrier against non-stomatal water loss and environmental damage coats the aerial surfaces of land plants. It comprises a cutin polymer matrix and waxes. Cuticular waxes are complex mixtures of very long chain fatty acids (VLCFAs) and their derivatives. Results show that primary alcohols are the major components of bread wheat (Triticum aestivum L.) leaf blade cuticular waxes. Here, the characterization of TaFAR5 from wheat cv Xinong 2718, which is allelic to TAA1b, an anther-specific gene, is reported. Evidence is presented for a new function for TaFAR5 in the biosynthesis of primary alcohols of leaf blade cuticular wax in wheat. Expression of TaFAR5 cDNA in yeast (Saccharomyces cerevisiae) led to production of C22:0 primary alcohol. The transgenic expression of TaFAR5 in tomato (Solanum lycopersicum) cv MicroTom leaves resulted in the accumulation of C26:0, C28:0, and C30:0 primary alcohols. TaFAR5 encodes an alcohol-forming fatty acyl-coenzyme A reductase (FAR). Expression analysis revealed that TaFAR5 was expressed at high levels in the leaf blades, anthers, pistils, and seeds. Fully functional green fluorescent protein-tagged TaFAR5 protein was localized to the endoplasmic reticulum (ER), the site of primary alcohol biosynthesis. SDS–PAGE analysis indicated that the TaFAR5 protein possessed a molecular mass of 58.4kDa, and it was also shown that TaFAR5 transcript levels were regulated in response to drought, cold, and abscisic acid (ABA). Overall, these data suggest that TaFAR5 plays an important role in the synthesis of primary alcohols in wheat leaf blade. [ABSTRACT FROM PUBLISHER]