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Triterpenoids have been described in Andrographis paniculata. Oleanolic acid exhibits high biological activity and is widely used in the clinic, and β-sitosterol not only has good biological activity but also plays an important physiological role in plants. However, analysis of the biosynthetic pathway of triterpenoids in Andrographis paniculata has not been reported. Here, we provide the first report of the isolation and identification of nine 2, 3-oxidosqualene cyclases (ApOSC3 to ApOSC11) from A. paniculata. The results showed that ApOSC4 represented a monofunctional synthase that could convert 2, 3-oxidosqualene to β-amyrin. ApOSC5 as a bifunctional 2, 3-oxidosqualene cyclases, could transfer 2, 3-oxidosqualene to β-amyrin and α-amyrin. ApOSC6 to ApOSC8 composed the multifunctional 2, 3-oxidosqualene cyclases that could convert 2, 3-oxidosqualene to β-amyrin, α-amyrin and one or two undetermined triterpenoids. This study provides a better understanding of the biosynthetic pathway of triterpenoids in A. paniculata, and the discovery of multifunctional 2, 3-oxidosqualene cyclases ApOSC5 to ApOSC8 of the facilitates knowledge of the compounds diversity in A. paniculata.

In the soybean cultivar Suweon 97, BCMV-resistance gene was fine-mapped to a 58.1-kb region co-localizing with the Soybean mosaic virus (SMV)-resistance gene, Rsv1-h raising a possibility that the same gene is utilized against both viral pathogens. Certain soybean cultivars exhibit resistance against soybean mosaic virus (SMV) or bean common mosaic virus (BCMV). Although several SMV-resistance loci have been reported, the understanding of the mechanism underlying BCMV resistance in soybean is limited. Here, by crossing a resistant cultivar Suweon 97 with a susceptible cultivar Williams 82 and inoculating 220 F2 individuals with a BCMV strain (HZZB011), we observed a 3:1 (resistant/susceptible) segregation ratio, suggesting that Suweon 97 possesses a single dominant resistance gene against BCMV. By performing bulked segregant analysis with 186 polymorphic simple sequence repeat (SSR) markers across the genome, the resistance gene was determined to be linked with marker BARSOYSSR_13_1109. Examining the genotypes of nearby SSR markers on all 220 F2 individuals then narrowed down the gene between markers BARSOYSSR_13_1109 and BARSOYSSR_13_1122. Furthermore, 14 previously established F2:3 lines showing crossovers between the two markers were assayed for their phenotypes upon BCMV inoculation. By developing six more SNP (single nucleotide polymorphism) markers, the resistance gene was finally delimited to a 58.1-kb interval flanked by BARSOYSSR_13_1114 and SNP-49. Five genes were annotated in this interval of the Williams 82 genome, including a characteristic coiled-coil nucleotide-binding site-leucine-rich repeat (CC-NBS-LRR, CNL)-type of resistance gene, Glyma13g184800. Coincidentally, the SMV-resistance allele Rsv1-h was previously mapped to almost the same region, thereby suggesting that soybean Suweon 97 likely relies on the same CNL-type R gene to resist both viral pathogens.

To explore the therapeutical effect of ear-acupoint pressing combined with Ear Apex (HX6,7) bloodletting on haemorheology in chloasma patients with Gan (Liver) depression pattern.A total of 180 chloasma patients were randomly assigned to three groups, 60 cases in each. Patients in the earacupuncture (EA) group were treated with ear-acupoint pressing combined with Ear Apex (HX6,7) bloodletting; vitamins C and E were put into practice in the Western medicine (WM) group together with 0.025% tretinoin cream for local external application; patients in the placebo group were treated with urea-cream by external use, while 30 healthy volunteers were in the control group. After a treatment course of 2 months, the changes of haemorheology, injury skin area, colour score and symptom score before and after the treatment were observed.There was no significant difference on whole blood reduced viscosity (high shear, medium shear, and low shear), erythrocyte aggregation index, hematocrit, plasma viscosity among the four groups (F =2.65, P0.05). Compared with those before treatment, the whole blood viscosity (high shear) and whole blood reduced viscosity (high shear) after treatment in the EA group, the WM group and the placebo group were with no statistical significance (P0.05). The injury skin area and colour score after treatment were significantly lower than those before treatment in the EA group and the WM group (P0.05), while there was no significant difference in placebo group (P0.05). Clinical symptoms of the EA group were obviously improved after the 2-month treatment, which was significantly different compared with those before treatment (P0.05), there was significant difference compared with those of WM group and placebo group (P0.05).There was no significant difference on haemorheology index between healthy people and chloasma patients without angionosis, cerebrovascular disease, hematopathy, metabolic disease or any other organic disease. Ear-acupoint pressing combined with Ear Apex (HX6,7) bloodletting can effectively improve concurrent symptoms, lighten chloasma and lower chloasma area in patients accompanied by Gan depression.

A major soybean (Forrest cultivar) quantitative trait locus (QTL) gene, Rhg4, which controls resistance to soybean cyst nematodes (SCN), encodes the enzyme serine hydroxylmethyltransferase (SHMT). The resistant allele possesses two critical missense mutations (P130R and N358Y) compared to that of the sensitive allele, rhg4. To understand the evolutionary history of this gene, sequences of 117 SHMT family members from 18 representative plant species were used to reconstruct their phylogeny. According to this phylogeny, the plant SHMT gene family can be divided into two groups and four subgroups (Ia, Ib, IIa and IIb). Belonging to the Subgroup Ia lineage, the rhg4 gene evolved from a recent duplication event in Glycine spp. To further explore how the SCN-resistant allele emerged, both the rhg4 gene and its closest homolog, the rhg4h gene, were isolated from 33 cultivated and 68 wild soybean varieties. The results suggested that after gene duplication, the soybean rhg4 gene accumulated a higher number of nonsynonymous mutations than rhg4h did. Although a higher number of segregating sites and gene haplotypes were detected in wild soybeans than in cultivars, the SCN-resistant Rhg4 allele (represented by haplotype 4) was not found in wild varieties. Instead, a very similar allele, haplotype 3, was observed in wild soybeans at a frequency of 7.4%, although it lacked the two critical nonsynonymous substitutions. Taken together, these findings support that the SCN-resistant Rhg4 allele likely emerged via artificial selection during the soybean domestication process, based on a SCN-sensitive allele inherited from wild soybeans.

The Rsv1 - h gene in cultivar Suweon 97, which confers resistance to SMVs, was mapped to a 97.5-kb location (29,815,195–29,912,667 bp on chromosome 13) in the Rsv1 locus, thereby providing additional insights into the molecular nature underlying variations in resistance alleles in this particular locus. Soybean mosaic virus (SMV) is a well-known devastating pathogen of soybean (Glycine max (L.) Merrill.) causing significant yield losses and seed quality deterioration. A single dominant allele, Rsv1-h, which confers resistance to multiple SMV strains, was previously reported in the cultivar Suweon 97, but its exact location is unknown. In the present study, Suweon 97 was crossed with a SMV-sensitive cultivar, Williams 82. Inoculating 267 F 2 individuals with two Chinese SMV strains (SC6-N and SC7-N) demonstrated that one single dominant gene confers SMV resistance. Another 1,150 F 2 individuals were then screened for two simple sequence repeat (SSR) markers (BARCSOYSSR_13_1103 and BARCSOYSSR_13_1187) that flank the Rsv1 locus. Seventy-four recombinants were identified and 20 additional polymorphic SSR markers within the Rsv1 region were then employed in genotyping these recombinants. F 2:3 and F 3:4 recombinant lines were also inoculated with SC6-N and SC7-N to determine their phenotypes. The final data revealed that in Suweon 97, the Rsv1-h gene that confers resistance to SC6-N and SC7-N was flanked by BARCSOYSSR_13_1114 and BARCSOYSSR_13_1115, two markers that delimit a 97.5-kb region in the reference Williams 82 genome. In such region, eight genes were present, of which two, Glyma13g184800 and Glyma13g184900, encode the characteristic CC-NBS-LRR type of resistance gene and were considered potential candidates for Rsv1-h.

A majority of land plants can form symbiosis with arbuscular mycorrhizal (AM) fungi. MicroRNAs (miRNAs) have been implicated to regulate this process in legumes, but their involvement in non-legume species is largely unknown. In this study, by performing deep sequencing of sRNA libraries in tomato roots and comparing with tomato genome, a total of 700 potential miRNAs were predicted, among them, 187 are known plant miRNAs that have been previously deposited in miRBase. Unlike the profiles in other plants such as rice and Arabidopsis, a large proportion of predicted tomato miRNAs was 24 nt in length. A similar pattern was observed in the potato genome but not in tobacco, indicating a Solanum genus-specific expansion of 24-nt miRNAs. About 40% identified tomato miRNAs showed significantly altered expressions upon Rhizophagus irregularis inoculation, suggesting the potential roles of these novel miRNAs in AM symbiosis. The differential expression of five known and six novel miRNAs were further validated using qPCR analysis. Interestingly, three up-regulated known tomato miRNAs belong to a known miR171 family, a member of which has been reported in Medicago truncatula to regulate AM symbiosis. Thus, the miR171 family likely regulates AM symbiosis conservatively across different plant lineages. More than 1000 genes targeted by potential AM-responsive miRNAs were provided and their roles in AM symbiosis are worth further exploring.