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Aquilaria sinensis is an important non-timber tree species for producing high-value agarwood, which is widely used as a traditional medicine and incense. Agarwood is the product of Aquilaria trees in response to injury and fungal infection. The APETALA2/ethylene responsive factor ( AP2/ERF) transcription factors (TFs) play important roles in plant stress responses and metabolite biosynthesis. In this study, 119 AsAP2/ERF genes were identified from the A. sinensis genome and divided into ERF, AP2, RAV, and Soloist subfamilies. Their conserved motif, gene structure, chromosomal localization, and subcellular localization were characterized. A stress/defense-related ERF-associated amphiphilic repression (EAR) motif and an EDLL motif were identified. Moreover, 11 genes that were highly expressed in the agarwood layer in response to whole-tree agarwood induction technique (Agar-Wit) treatment were chosen, and their expression levels in response to methyl jasmonate (MeJA), salicylic acid (SA), or salt treatment were further analyzed using the quantitative real time PCR (qRT-PCR). Among the 11 genes, eight belonged to subgroup B-3. All 11 genes were significantly upregulated under salt treatment, while eight genes were significantly induced by both MeJA and SA. In addition, the gene clusters containing these upregulated genes on chromosomes were observed. The results obtained from this research not only provide useful information for understanding the functions of AP2/ERF genes in A. sinensis but also identify candidate genes and gene clusters to dissect their regulatory roles in agarwood formation for future research.

Si-Yu Long,1 Le Wang,1,2 Hai-Qin Jiang,1 Ying Shi,1 Wen-Yue Zhang,1 Jing-Shu Xiong,1 Pei-Wen Sun,1,2 Yan-Qing Chen,1 You-Ming Mei,1 Chun Pan,1 Gai Ge,1 Zhen-Zhen Wang,1 Zi-Wei Wu,1 Mei-Wen Yu,1,2 Hong-Sheng Wang1– 3 1Jiangsu Key Laboratory of Molecular Biology for Skin Diseases and STIs, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, 210042, People’s Republic of China; 2National Centre for Leprosy Control, China CDC, Nanjing, People’s Republic of China; 3Centre for Global Health, School of Public Health, Nanjing Medical University, Nanjing, People’s Republic of ChinaCorrespondence: Hong-Sheng Wang; Mei-Wen YuJiangsu Key Laboratory of Molecular Biology for Skin Diseases and STIs, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, St 12 Jiangwangmiao, Nanjing, Jiangsu, 210042, People’s Republic of ChinaEmail whs33@vip.sina.com; yumeiwen@163.comBackground: Genome-wide association studies (GWASs) have identified some immune-related single-nucleotide polymorphisms (SNPs) to be associated with leprosy.Methods: This study investigated the association of 17 SNPs based on previously published GWAS studies with susceptibility to leprosy, different polar forms and immune states of leprosy in a case–control study from southwestern China, including 1344 leprosy patients and 2732 household contacts (HHCs) (1908 relatives and 824 genetically unrelated contact individuals). The differences of allele distributions were analyzed using chi-squared analysis and logistic regression.Results: After adjusting covariate factors, rs780668 and rs3764147 polymorphisms influenced susceptibilities to genetically related or unrelated leprosy contact individuals. rs142179458 was associated with onset early cases, rs73058713 A allele and rs3764147 A allele increased the risk of reversal reaction, while rs3764147 G allele had higher risk to present lepromatous leprosy and erythema nodosum leprosum.Conclusion: Our results demonstrated that genetic variants in the LACC1, HIF1A, SLC29A3 and CDH18 genes were positively correlated with the occurrence of leprosy and leprosy clinical phenotypes, providing new insights into the immunogenetics of the disease.Keywords: leprosy, association study, susceptibility gene, polymorphisms

Adventitious root branching is vital to plant growth and regeneration, but the regulation of this process remains unclear. We therefore investigated how ginsenosides regulate adventitious root branching in Panax ginseng. Cell proliferation and adventitious root branching were decreased in the presence of ginsenoside Rb1 and a high concentration of ginsenoside Re, but increased when treating with a low concentration of Re. Moreover, the exogenous application of a synthetic dodeca-amino acid peptide that has a CLAVATA3/EMBRYO SURROUNDING REGION-related (CLE) motif corresponding to PgCLE45 retarded root growth in both ginseng and Arabidopsis. The root Re levels and the expression of the DDS, CYP716A47, and CYP716A53 genes that encode enzymes involved in ginsenoside synthesis were decreased in the presence of PgCLE45. The expression profiles of PgWOX and PgCLE genes were determined to further investigate the CLE–WOX signaling pathway. The levels of PgWOX11 transcripts showed an inverse pattern to PgCLE45 transcripts. Using yeast one-hybrid assay, EMSA, and ChIP assay, we showed that PgWOX11 bound to the PgCLE45 promoter, which contained the HD motif. Transient expression assay showed that PgWOX11 induced the expression of PgCLE45 in adventitious roots, while PgCLE45 suppressed the expression of PgWOX11. These results suggest that there is a negative feedback regulation between PgCLE45 and PgWOX11. Taken together, these data show that ginsenosides regulate adventitious root branching via a novel PgCLE45–PgWOX11 regulatory loop, providing a potential mechanism for the regulation of adventitious root branching.

Background There is a high incidence of leprosy among house-contacts compared with the general population. We aimed to establish a predictive model using these genetic factors along with epidemiological factors to predict leprosy risk of leprosy household contacts (HHCs). Methods Weighted genetic risk score (wGRS) encompassing genome wide association studies (GWAS) variants and five non-genetic factors were examined in a case–control design associated with leprosy risk including 589 cases and 647 controls from leprosy HHCs. We constructed a risk prediction nomogram and evaluated its performance by concordance index (C-index) and calibration curve. The results were validated using bootstrap resampling with 1000 resamples and a prospective design including 1100 HHCs of leprosy patients. Finding The C-index for the risk model was 0·792 (95% confidence interval [CI] 0·768-0·817), and was confirmed to be 0·780 through bootstrapping validation. The calibration curve for the probability of leprosy showed good agreement between the prediction of the nomogram and actual observation. HHCs were then divided into the low-risk group (nomogram score ≤ 81) and the high-risk group (nomogram score > 81). In prospective analysis, 12 of 1100 participants had leprosy during 63 months’ follow-up. We generated the nomogram for leprosy in the validation cohort (C-index 0·773 [95%CI 0·658-0·888], sensitivity75·0%, specificity 66·8%). Interpretation The nomogram achieved an effective prediction of leprosy in HHCs. Using the model, the risk of an individual contact developing leprosy can be determined, which can lead to a rational preventive choice for tracing higher-risk leprosy contacts. Funding The ministry of health of China, ministry of science and technology of China, Chinese academy of medical sciences, Jiangsu provincial department of science and technology, Nanjing municipal science and technology bureau.

Objective: To describe the epidemiological characteristics of leprosy in China in 2018 and provide the essential evidences for leprosy control. Methods: We collected data of leprosy cases nationwide from Leprosy Management Information System in China (LEPMIS) except Hong Kong, Macao, and Taiwan. And then we performed a descriptive and comparative analysis. Results: A total of 521 new leprosy cases were detected nationwide in 2018, with a case detection rate of 0.037/100,000. The proportion of children under 15 years of age, multi-bacillary (MB) cases, and cases with WHO grade 2 disability (G2D) were 1.3%, 89.4%, and 19.0%, respectively. There were 2,479 registered cases of leprosy in China by the end of 2018, accounting for a prevalence rate of 0.178/100,000, with 43 replase cases. Southwest China separately accounted for 312/521 (59.9%) newly detected cases and 1,180/2,479 (47.6%) registered cases of leprosy in China. Conclusion: China is a low endemic country for leprosy and the detection rate was much lower than the global average. Southwest China is still the key regions for leprosy control, including Yunnan, Guizhou, and Sichuan. In addition, leprosy in low endemic provinces also needs to be focused. Key words: leprosy; epidemiology; China; endemic

Sesquiterpenes are one of the most important defensive secondary metabolite components of agarwood. Agarwood, which is a product of the Aquilaria sinensis response to external damage, is a fragrant and resinous wood that is widely used in traditional medicines, incense and perfume. We previously reported that jasmonic acid (JA) plays an important role in promoting agarwood sesquiterpene biosynthesis and induces expression of the sesquiterpene synthase ASS1, which is a key enzyme that is responsible for the biosynthesis of agarwood sesquiterpenes in A. sinensis. However, little is known about this molecular regulation mechanism. Here, we characterized a basic helix-loop-helix transcription factor, AsMYC2, from A. sinensis as an activator of ASS1 expression. AsMYC2 is an immediate-early jasmonate-responsive gene and is co-induced with ASS1. Using a combination of yeast one-hybrid assays and chromatin immunoprecipitation analyses, we showed that AsMYC2 bound the promoter of ASS1 containing a G-box motif. AsMYC2 activated expression of ASS1 in tobacco epidermis cells and up-regulated expression of sesquiterpene synthase genes (TPS21 and TPS11) in Arabidopsis, which was also promoted by methyl jasmonate. Our results suggest that AsMYC2 participates in the regulation of agarwood sesquiterpene biosynthesis in A. sinensis by controlling the expression of ASS1 through the JA signaling pathway.

Agarwood is derived from wounded Aquilaria trees and is widely used in traditional medicine, incense, and perfume. Sesquiterpenes are one of the main active components in agarwood and are known to be induced by wounding or injury. The molecular mechanism by which wounding leads to sesquiterpene formation remains largely unknown. ASS1 is one of key enzymes responsible for the biosynthesis of sesquiterpenes and is a pivotal jasmonate (JA)-responsive wound-inducible synthase. However, why ASS1 does not express in healthy trees and how its expression is induced as a result of wounding remains unexplored. Here, we report that ASS1 is a wound-induced gene with a promoter in which the 242-bp (-973 to -731bp) region is identified as the core sequence for responding to wound signals. AsWRKY44 binds directly to this region and represses ASS1 promoter activity. Downregulation or disruption of AsWRKY44 can relieve the inhibition and activate ASS1 expression. Further, it is found that in response to the exogenous MeJA, AsWRKY44 is degraded and the expression of ASS1 is significantly upregulated. These findings confirm AsWRKY44 is a crucial negative regulator involved in the regulation of wound-induced ASS1 transcription, which reveals the core mechanism of agarwood sesquiterpenes biosynthesis.

The WRKY proteins are a superfamily of transcription factor that regulate diverse developmental and physiological processes in plants. Completion of the whole-genome sequencing of Aquilaria sinensis allowed us to perform a genome-wide investigation for WRKY proteins. Here, we predicted 70 WRKY genes from the A. sinensis genome and undertaken a comprehensive bioinformatic analysis. Due to their diverse structural features, the 70 AsWRKY genes are classified into three main groups (group I–III), with five subgroups (IIa–IIe) in group II, except two belong to none of them. Distinct expression profiles of AsWRKYs with RNA sequencing data revealed their diverse expression patterns among different tissues and in the process of whole-tree-inducing agarwood formation. Based on the expression characteristics, we predict some AsWRKYs are pseudogenes, and some may be involved in the biosynthesis of agarwood sesquiterpenes as activators or repressors. Among the tested genes treated with MeJA and H2O2, most of them are induced by H2O2, but downregulated by MeJA, implying the complexity of their involvement in signal transduction regulation. Our results not only provide a basic platform for functional identification of WRKYs in A. sinensis but important clues for further analysis their regulation role in agarwood formation.

Agarwood is derived from wounds in Aquilaria trees and is widely used in traditional medicine, incense, and perfume. Sesquiterpenes are one of the main active components in agarwood and are known to be induced by wounding or injury; However, the molecular mechanisms by which wounding leads to sesquiterpene formation remain largely unknown. Agarwood sesquiterpene synthase 1 (ASS1) is one of key enzymes responsible for the biosynthesis of sesquiterpenes and is a crucial jasmonate (JA)-responsive wound-inducible synthase. However, it is not known why ASS1 is not expressed in healthy trees and how its expression is induced as a result of wounding. Here, we report that ASS1 is a wound-induced gene with a promoter in which a 242-bp region (-973 to -731bp) is identified as the core sequence for responding to wound signals. AsWRKY44 binds directly to this region and represses ASS1 promoter activity. Down-regulation or disruption of AsWRKY44 can relieve the inhibition and activate ASS1 expression. In addition, AsWRKY44 is degraded and the expression of ASS1 is significantly up-regulated in response to exogenous application of methyl jasmonate. Thus, AsWRKY44 is a crucial negative regulator of wound-induced ASS1 transcription, and is central to the mechanism of sesquiterpene biosynthesis in agarwood.

Agarwood, a highly valuable resinous and fragrant heartwood of Aquilaria plants, is widely used in traditional medicines, incense and perfume. Only when Aquilaria trees are wounded by external stimuli do they form agarwood sesquiterpene defensive compounds. Therefore, understanding the signaling pathway of wound-induced agarwood formation is important. Jasmonic acid (JA) is a well-characterized molecule that mediates a plant’s defense response and secondary metabolism. However, little is known about the function of endogenous JA in agarwood sesquiterpene biosynthesis. Here, we report that heat shock can up-regulate the expression of genes in JA signaling pathway, induce JA production and the accumulation of agarwood sesquiterpene in A. sinensis cell suspension cultures. A specific inhibitor of JA, nordihydroguaiaretic acid (NDGA), could block the JA signaling pathway and reduce the accumulation of sesquiterpene compounds. Additionally, compared to SA and H2O2, exogenously supplied methyl jasmonate has the strongest stimulation effect on the production of sesquiterpene compounds. These results clearly demonstrate the central induction role of JA in heat-shock-induced sesquiterpene production in A. sinensis.

Background: Although the World Health Organization (WHO) has defined relapse in leprosy, it is often difficult to confirm a relapse, especially in paucibacillary (PB) patients. Objective: To study features of relapse cases in order to determine the information needed to allow better management of relapses in the leprosy control programme. Design: A retrospective survey by questionnaire was carried out at national level at the end of 2012. Results: There were 40 relapsed patients on register. The clinical form of leprosy was TT5, BT4, BB5, BL13 and LL13. Twenty-eight patients had had a positive skin smear test at the start of MDT, with a BI ranging from 0.83 to 6.0. At the time of completing MDT, the skin smear test remained positive in seven patients. After completion of MDT, other family members of 13 patients were identified as new leprosy patients. All relapse cases showed one or more active skin lesions. There were 33 patients with a positive skin smear test at the time of relapse. A total of 23 patients had a biopsy at the time of relapse, including seven patients with a negative skin smear test. The histological features of relapsed BB-LL patients included granulomas containing macrophages or epithelioid cells with sparse lymphocytes and acid-fast bacilli. The histological features of seven patients with negative skin smears showed epithelioid cell granulomas with dense lymphocytes surrounding the granuloma, but without distinct edema in the dermis. The average interval from completion of MDT to the diagnosis of relapse was 168.5 ± 92.6 months with a range of 21–322 months. During the study, nine patients were tested for rifampicin resistance, but none showed any mutation. Conclusions: Leprosy relapse after MDT usually occurred late and all relapse cases had new active skin lesions. Most patients relapsed with a positive skin smear after previously reaching negative BI status. Relapse with a negative skin smear test should be confirmed very cautiously.

The increasing pressure of modern social life intensifies the impact of stress on the development of cardiovascular diseases, which include deep venous thrombosis (DVT). Renal sympathetic denervation has been applied as one of the clinical approaches for the treatment of drug-resistant hypertension. In addition, the close relationship between oxidative stress and cardiovascular diseases has been well documented. The present study is designed to explore the mechanism by which the renal sympathetic nerve system and the oxidative stress affect the blood coagulation system in the development of DVT. Chronic foot shock model in rats was applied to mimic a state of physiological stress similar to humans. Our results showed that chronic foot shock procedure could promote DVT which may be through the activation of platelets aggregation. The aggravation of DVT and activation of platelets were alleviated by renal sympathetic denervation or antioxidant (Tempol) treatment. Concurrently, the denervation treatment could also reduce the levels of circulating oxidation factors in rats. These results demonstrate that both the renal sympathetic nerve system and the oxidative stress contribute to the development of DVT in response to chronic stress, which may provide novel strategy for treatment of clinic DVT patients.

We developed a Questionnaire on Everyday Navigational Ability (QuENA) to detect topographical disorientation (TD) in patients with Alzheimer’s disease (PwAD). In the QuENA, 3 items were designed to assess landmark agnosia, 2 for egocentric disorientation, 3 for heading disorientation, and 2 for inattention. The PwAD and their caregivers rated QuENA according to which TD symptoms would occur. Regarding the construct validity, confirmatory factor analysis showed that the caregiver version of the QuENA fits the proposed TD model well but the patient version does not. Regarding the internal consistency, the Cronbach’s α for the caregiver version was 0.91 and that for the patient version was 0.87. A discrepancy existed between the appraisal of navigational abilities by PwAD and by caregivers, and it was correlated with the number of getting lost (GL) events. The caregiver version of QuENA is a feasible, reliable, and valid instrument to assess TD and it also discriminates well between the PwAD with GL and those without.