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Mungbean [Vigna radiata (L.) R. Wilczek var. radiata] is an important legume crop for South East Asia. Smallholder farmers rely on this crop to diversify income streams and enrich soils through N-fixation. To produce new varieties that stabilize mungbean productivity under biotic and abiotic stresses, breeders need to take advantage of genomic tools. Genome-Wide Association Studies (GWAS) are an effective strategy to associate agronomic traits with underlying genes. A key factor to avoid false associations in GWAS is a thorough understanding of the population structure. In this study, we analyzed the population structure of the World Vegetable Center’s (WorldVeg) mungbean mini core collection and performed a GWAS to identify loci associated with seed coat luster (SCL) utilizing SNP markers. The mini core collection consisted of 297 most genetically diverse accessions selected from 6700 global accessions held by the WorldVeg genebank. Genotyping by Sequencing (GBS) produced a total of 24,870 Single Nucleotide Polymorphism (SNP) markers. After filtering, 5288 highly polymorphic SNPs were used for analysis. Population structure analysis predicted four sub-populations based on the non-parametric Wilcoxon test. Linkage disequilibrium (LD) was found to decline to half of the maximal r2 value at approximately 350 kb; and a pilot GWAS study investigating seed coat luster (SCL) revealed two loci in chromosome 5 significantly associated with SCL.

Dysfunctional mitochondria have been shown to enhance cancer cell proliferation, reduce apoptosis, and increase chemoresistance. Chemoresistance develops in nearly all patients with colorectal cancer, leading to a decrease in the therapeutic efficacies of anticancer agents. However, the effect of dynamin-related protein 1 (Drp1)-mediated mitochondrial fission on chemoresistance in colorectal cancer is unclear. Here, we found that the release of high-mobility group box 1 protein (HMGB1) in conditioned medium from dying cells by chemotherapeutic drugs and resistant cells, which triggered Drp1 phosphorylation via its receptor for advanced glycation end product (RAGE). RAGE signals ERK1/2 activation to phosphorylate Drp1 at residue S616 triggerring autophagy for chemoresistance and regrowth in the surviving cancer cells. Abolishment of Drp1 phosphorylation by HMGB1 inhibitor and RAGE blocker significantly enhance sensitivity to the chemotherapeutic treatment by suppressing autophagy. Furthermore, patients with high phospho-Drp1Ser616 are associated with high risk on developing tumor relapse, poor 5-year disease-free survival (DFS) and 5-year overall survival (OS) after neoadjuvant chemoradiotherapy (neoCRT) treatment in locally advanced rectal cancer (LARC). Moreover, patients with RAGE-G82S polymorphism (rs2070600) are associated with high phospho-Drp1Ser616 within tumor microenvironment. These findings suggest that the release of HMGB1 from dying cancer cells enhances chemoresistance and regrowth via RAGE-mediated ERK/Drp1 phosphorylation.

Tomato yellow leaf curl disease caused by different begomovirus species leads to substantial tomato production losses worldwide. In Taiwan, the monopartite tomato leaf curl Taiwan virus (ToLCTWV) and bi-partite tomato yellow leaf curl Thailand virus (TYLCTHV) are the predominant begomovirus species causing this disease. Resistance genes are available in wild tomato species and a continuous search for new resistance genes and alternative control methods is required to respond to the rapid evolution of virus strains. RNA interference is an efficient technology to induce resistance against viral pathogens. Six different sections of the ToLCTWV genome were tested in transformed tomato for their capacity to reduce symptoms and inhibit viral DNA accumulation. The two most effective constructs for ToLCTWV infection carried regions of the C1 and C2 genes, and portions of either the C3 or C4 gene of ToLCTWV. A RNAi construct containing fusions of C1, C2 and C3 sections of ToLCTWV and the corresponding sections of the TYLCTHV DNA-A genome were introgressed into tomato line CLN1621L. R1 and R2 families were challenged using viruliferous whiteflies in separate screen houses for ToLCTWV and TYLCTHV. Sixteen and 12 R2 plants derived from one primary transformant remained symptomless until at least 3 weeks after exposure to ToLCTWV and TYLCTHV, respectively, and accumulated only very low titres of viral DNA, as shown by real-time polymerase chain reaction analysis. Our results suggest that expression of bi-viral RNAi constructs in tomato can lead to resistance against two different tomato infecting begomovirus species.

This study aims to apply analytic hierarchy process method by surveying social media network (SMN) users to identify the importance of four major criteria and 16 sub-criteria. This research interviews SMN users who have experienced in using Facebook, Twitter and Pinterest. The result shows that social-integration plays an important role for Facebook users, whereas self-integration plays critical role for Twitter and Pinterest users. By identifying the most essential criteria, self-integration is the most essential criterion whereas social-interaction is the least important criterion identified for SMN users. The results can be reapplied for future update SMN sites for evaluation to deliver a new market analysis and to gain competitive advantages.

Background Bruchid beetles are an important storage pest of grain legumes. Callosobruchus sp. infect mungbean (Vigna radiata) at low levels in the field, multiply during grain storage and can destroy seed stocks in a few months. Resistance against bruchid beetles has been found in wild mungbean V. radiata var. sublobata TC1966 and in cultivated mungbean line V2802. Results Bruchid resistance data were obtained from recombinant inbred line populations TC1966 (V. radiata var. sublobata) × NM92 (F12) and V2802 (V. radiata) × NM94 (F7). More than 6,000 single nucleotide polymorphic markers were generated through genotyping by sequencing (GBS) for each of these populations and were used to map bruchid resistance genes. One highly significant quantitative trait locus (QTL) associated with bruchid resistance was mapped to chromosome 5 on genetic maps of both populations, suggesting that TC1966 and V2802 contain the same resistance locus. Co-segregation of all markers associated with resistance indicated the presence of only one major resistance QTL on chromosome 5, while QTL analysis based on physical map positions of the markers suggested the presence of multiple QTLs on different chromosomes. The diagnostic capacity of the identified molecular markers located in the QTL to correctly predict resistance was up to 100 %. Conclusions Molecular markers tightly linked to bruchid resistance loci of two different mungbean resistance sources were developed and validated. These markers are highly useful for developing resistant lines. Electronic supplementary material The online version of this article (doi:10.1186/s12870-016-0847-8) contains supplementary material, which is available to authorized users.