Watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] is an economically important vegetable crop grown extensively worldwide. To facilitate the identification of agronomically important traits and provide new information for genetic and genomic research on this species, a high-density genetic linkage map of watermelon was constructed using an F2 population derived from a cross between elite watermelon cultivar K3 and wild watermelon germplasm PI 189225. Based on a sliding window approach, a total of 1,161 bin markers representing 3,465 SNP markers were mapped onto 11 linkage groups corresponding to the chromosome pair number of watermelon. The total length of the genetic map is 1,099.2 cM, with an average distance between bins of 1.0 cM. The number of markers in each chromosome varies from 62 in chromosome 07 to 160 in chromosome 05. The length of individual chromosomes ranged between 61.8 cM for chromosome 07 and 140.2 cM for chromosome 05. A total of 616 SNP bin markers showed significant (P < 0.05) segregation distortion across all 11 chromosomes, and 513 (83.3 %) of these distorted loci showed distortion in favor of the elite watermelon cultivar K3 allele and 103 were skewed toward PI 189225. The number of SNPs and InDels per Mb varied considerably across the segregation distorted regions (SDRs) on each chromosome, and a mixture of dense and sparse SNPs and InDel SDRs coexisted on some chromosomes suggesting that SDRs were randomly distributed throughout the genome. Recombination rates varied greatly among each chromosome, from 2.0 to 4.2 centimorgans per megabase (cM/Mb). An inconsistency was found between the genetic and physical positions on the map for a segment on chromosome 11. The high-density genetic map described in the present study will facilitate fine mapping of quantitative trait loci, the identification of candidate genes, map-based cloning, as well as marker-assisted selection (MAS) in watermelon breeding programs.

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Diabetes mellitus is the most serious and prevalent metabolic disorders worldwide, complications of which can decrease significantly the quality of life and contribute to premature death. Resistance to insulin is a predominant pathophysiological factor of Type 2 diabetes (T2D). Protein tyrosine phosphatase 1B (PTP1B) is an important negative factor of insulin signal and a potent therapeutic target in T2D patients. This review highlights recent advances (2012-2015) in research related to the role of PTP1B in signal transduction processes implicated in pathophysiology of T2D, and novel PTP1B inhibitors with an emphasis on their chemical structures and modes of action.

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Emerging data suggests that mitochondrial dysfunction is prominently involved in Alzheimer disease (AD) progression. Sirtuin-3 (Sirt3) is a member of the sirtuin family of nicotinamide adenine dinucleotide dependent deacetylases that regulates a variety of mitochondrial functions and suppresses mitochondria-related physiology. Here, we determined sirt3 expression in a mouse model of AD. Spatial learning and memory were tested by Morris water maze in APP/PS1 double transgenic mice. The expression of sirt3 was assayed by real-time quantitative PCR and western blotting. Age-and gender-matched wild-type (WT) littermates were used as controls. Cortical sirt3 localization was assessed using immunohistochemistry. The expression of sirt3 mRNA was significantly lower in the cortex of APP/PS1 double transgenic mice than in WT littermates (0.83 ± 0.24 vs. 1.10 ± 0.21, P < 0.05). A comparable reduction was found in sirt3 protein levels using western blotting. The ratio of mean optical density (MOD) of total sirt3/β-actin in the cortex was 0.77 ± 0.11 in APP/PS1 double transgenic mice and 1.34 ± 0.17 in the WT littermates (P < 0.01). Immunohistochemistry showed the same change as western blotting. The ratio of MOD of integral optical density/total area in APP/PS1 and WT littermates was 0.58 ± 0.02 and 0.71 ± 0.05 (P < 0.01). These data show that sirt3 was depleted in APP/PS1 double transgenic mice. The results suggest that mitochondrial sirt3 might participate in the development of AD via mitochondrial dysfunction.

Methyl jasmonate (MeJA) is one of the most potent elicitors that can induce over accumulation of many natural products including artemisinin in plants. The 12 known genes (HMGR, DXS, DXR, HDS, HDR, FPS, ADS, CYP71AV1, DBR2, ALDH1, ORA and ERF1) of terpene metabolism in Artemisia annua were dynamically analyzed at the transcriptional levels in the treatment of MeJA from 0 to 48 h. HMGR (MVA pathway) showed higher expression level when the plants were treated with MeJA from 1 to 9 h and had the highest expression level at 3 h MeJA treatment. The expression levels of DXS and DXR (MEP pathway) reached the peak at 9 h. The last two genes of the MEP pathway, such as HDS and HDR, had the highest expression levels at 24 h. The expression of FPS increased significantly in the treatment of MeJA from 1 to 48 h, and the highest expression level appeared at 24 and 48 h after the MeJA treatment. Four genes in artemisininspecific biosynthetic pathway including ADS, CYP71AV1, DBR2 and ALDH1 had higher expression levels in the treatment of MeJA from 1 to 48 h. The expression levels of two transcription factors such as ORA and ERF1 were also enhanced. The contents of artemisinin in the plants treated with MeJA for 24 and 48 h were respectively 0.971 and 0.973 mg/g DW, about 1.16-fold of the control (0.809 mg/ g DW). Taken together, these results suggested that MeJA induced artemisinin biosynthesis by up-regulating the expression of the genes involved in artemisinin biosynthesis and the transcription factor. Keywords Artemisia annua Á MeJA Á Artemisinin Á Gene expressionAbbreviations ADS Amorpha-4,11-diene synthase ALDH1 Aldehyde dehydrogenase 1 CYP71AV1 Cytochrome P450 monooxygenase DBR2 Artemisinic aldehyde D11(13) reductase DMAPP Dimethylallyl diphosphate DXS 1-Deoxy-D-xylulose-5-phosphate synthase DXR 1-Deoxy-D-xylulose-5-phosphate reductoisomerase DW Dry weight ERF1 Ethylene response factor 1 ELSD Evaporative light scattering detector FPS Farnesyl pyrophosphate synthase Lien Xiang and Shunqin Zhu contributed to this work equally. Electronic supplementary material The online version of this article (

Watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai var. lanatus ] is an economically important vegetable belonging to the Cucurbitaceae family. Genotypes that exhibit agronomically important traits are selected for the development of elite cultivars. Understanding the genetic diversity and the genotype population structure based on molecular markers at the genome level can speed up the utilization of diverse genetic resources for varietal improvement. In the present study, we carried out an analysis of genetic diversity based on 3882 SNP markers across 37 core watermelon genotypes, including the most widely used watermelon varieties and wild watermelon. Based on the SNP genotyping data of the 37 watermelon genotypes screened, gene diversity and polymorphism information content values across chromosomes varied between 0.03 -0.5 and 0.02 -0.38, with averages of 0.14 and 0.13, respectively. The two wild watermelon genotypes were distinct from cultivated varieties and the remaining 35 cultivated genotypes were differentiated into three major clusters: 20 genotypes were grouped in cluster I; 11 genotypes were grouped in cluster II; three advanced breeding lines of yellow fruit flesh and genotype SW043 were grouped in cluster III. The results from neighbour-joining dendrogram, principal coordinate analysis and STRUCTURE analysis approaches were consistent, and the grouping of genotypes was generally in agreement with their origins. Here we reveal the genetic relationships among the core watermelon genotypes maintained at the Jiangsu Academy of Agricultural Sciences, China. The molecular and phenotypic characterization of the existing core watermelon genotypes, together with specific agronomic characteristics, can be utilized by researchers and breeders for future watermelon improvement.

The present study is designed to determine whether Huai Qi Huang has immunoregulatory effects on the (helper T (Th)) Th1/Th2 and regulatory T cell (Treg)/Th17 balance in ovalbumin (OVA)-induced asthma model mice. Asthma model mice were constructed by OVA treatment and Huai Qi Huang was administered. The amount of migrated inflammatory cells in the bronchoalveolar lavage fluid (BALF) from the OVA mice was counted. The total IgE in the sera was detected by the IgE ELISA kit. Cell suspensions from the lung were stained with antibodies specific for CD4 and the master transcription factors for Th1 (T-box expressed in T cells (T-bet)), Th2 (GATA-binding protein 3 (Gata-3)), Th17 (retinoic acid related orphan receptor γt (RORγt)), and Treg (forkhead box p3 (Foxp3)). The left lobe of the lung was used to prepare a single-cell suspension for flow cytometry to determine whether Huai Qi Huang influenced CD4+ T-cell subsets. Histological analyses were performed by using Hematoxylin and Eosin staining. The mRNA expression levels of the transcription factors were detected by using qRT-PCR. Huai Qi Huang inhibited infiltration of inflammatory cells into the lung, reduced influx of eosinophils (EOSs), lymphocytes (LYMs), neutrophils (NEUs), and macrophages (MACs) in the BALF, and decreased IgE in the serum in OVA-treated mice. Huai Qi Huang could regulate Th1/Th2 and Treg/Th17 via the re-balance of cytokine profiles and change the mRNA expression levels of the transcription factors, T-bet/Gata-3 and Foxp3/RORγt in OVA-treated mice. Our results showed that Huai Qi Huang could correct the imbalance of Th1/Th2 and Treg/Th17 in OVA-induced asthma model mice, indicating its effects on inhibiting the development and severity of asthma.