Biology subjects

Ge, Q.

Publications and source records attributed to Ge, Q..

23 records · Page 2Linked to original sources

bioRxiv2019

Moxifloxacin efficacy against Mycobacterium abscessus in vivo using zebrafish model

Moxifloxacin (MFX) showed good activity in vitro against Mycobacterium abscessus (M. abscessus) and was suggested as one of the antibiotic regimens for adults with M. abscessus disease. However, some other studies showed that MFX showed less or none activity against M. abscessus. In our study we aim to evaluate MFX activity against M. abscessus using zebrafish (ZF) model in vivo. MIC of each drugs were determined by broth microdilution method. M. abscessus labeled by CM-DiI, were micro-injected into ZF. Survival curves were determined by recording dead ZF every day. After 4 days of incubation ZF were lysed. Colony-forming unit (CFU) were enumerated and results are expressed as mean log10 CFU per ZF. Bacteria dissemination and fluorescence intensity in ZF were observed and analyzed. Inhibition rate was also calculated. In our study MFX showed good activity in vitro. But in vivo MFX showed limited restriction to M. abscessus. The association between increased survival and high dose of MFX is not significant. Same results were observed in bacterial fluorescence intensity and inhibition rates, with no significant difference when compared with no drug group (P > 0.05). However, significant difference was observed in azithromycin (AZM) group. MFX showed limited efficacy on Mycobacterium abscessus in vivo using ZF model. MFXs activity in vivo need to be confirmed.

microbiology↗

bioRxiv2019

Genome-wide quantitative trait loci mapping on Verticilliumw

Cotton Verticillium wilt (VW) is a devastating disease seriously affecting fiber yield and quality, and the most effective and economical prevention measure at present is selection and extension of Gossypium varieties harboring high resistant VW. However, multiple attempts to improve the VW resistance of the most widely cultivated Upland cotton have brought in little significant progress, and it seems necessary and urgent to develop Chromosome segment substitution lines (CSSLs) for merging the superior genes related with high yield and wide adaptation from G. hirsutum and VW resistance and excellent fiber quality from G. barbadense. In this study, 300 CSSLs were chosen from the developed BC5F3:5 CSSLs constructed by G. hirsutum CCRI36 and G. barbadense Hai1 to conduct quantitative trait locus (QTL) mapping on VW resistance, and a total of 53 QTLs relevant to VW disease index (DI) were identified together with the phenotypic data of 2 years investigations in two fields with two replications per year. All the QTLs were distributed on 20 chromosomes with phenotypic variation of 3.74-11.89%, of which 29 stable ones were consistent in at least two environments. Based on Meta-analysis on the 53 QTLs, 43 novel ones were identified, while 10 ones consistent to previously identified QTLs. Meanwhile, 32 QTL hotspot regions were detected, including 15 ones were novel. This study concentrates on QTL identification and screening hotspot region related with VW in the 300 CSSLs, which lay a solid platform not only for revealing the genetic and molecular mechanisms of VW resistance, but also for further fine mapping, gene cloning and molecular designing in breeding program for resistant cotton varieties.

plant biology↗

bioRxiv2018

KPNA2 promotes cellular proliferation and inhibits apoptosis in the Saos-2 osteosarcoma cell line

Karyopherin 2 plays a critical role in tumorigenesis and tumor progression. However, nothing is currently known about the effects of KPNA2 on osteosarcomas. This study aimed to investigate differential KPNA2 protein and mRNA expression in human osteosarcoma tumor cells and normal bone tissue. We also sought to determine whether KPNA2 can influence the proliferation and apoptosis of the Saos-2 osteosarcoma cell line. Immunohistochemistry (IHC) was used to investigate KPNA2 protein expression. Real-time quantitative PCR (qPCR) was used to detect levels of KPNA2 mRNA expression, and lentivirus-mediated short-hairpin RNAs (shRNAs) were used to knock down KPNA2 expression in Saos-2 cells. The MTT assay and multiparametric high-content screening (HCS) were used to measure cell proliferation and growth, respectively. Flow cytometry was conducted to detect cell cycle distribution and apoptosis. The results revealed significantly higher KPNA2 expression levels in osteosarcoma tissues than in normal bone tissues; furthermore, KPNA2 mRNA was also highly expressed in three osteosarcoma cell lines. After transducing Saos-2 cells with KPNA2-shRNA lentivirus, the proliferative rate was notably decreased compared to that of the negative control (NC) lentivirus group (P<0.05). Flow cytometry results indicated that KPNA2 may arrest cell cycle progression and regulate the growth of these cells. The results for apoptosis indicated an apoptotic rate of 13.38{+/-}0.48% in KPNA2-shRNA cells, which was significantly higher than the rate for cells in the control group (5.13 {+/-}0.33%). Therefore, this study showed that KPNA2 is highly expressed in osteosarcoma tissues and that reduced KPNA2mRNA levels inhibited proliferation and promoted apoptosis in an osteosarcoma cell line.

cancer biology↗

bioRxiv2018

Enhancement of Macrophage Function by the Antimicrobial Peptide Sublancin Protects Mice from Methicillin-Resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is the major pathogen responsible for community and hospital bacterial infections. Sublancin, a glocosylated antimicrobial peptide isolated from Bacillus subtilis 168, possesses anti-bacterial infective effects. In this study, we investigated the role and anti-infection mechanism of sublancin in a mouse model of MRSA-induced sublethal infection. Sublancin could modulate innate immunity by inducing the production of IL-1{beta}, IL-6, TNF- and nitric oxide, enhancing phagocytosis and MRSA-killing activity in both RAW264.7 cells and peritoneal macrophages. The enhanced macrophage function by the peptide in vitro correlated with stronger protective activity in vivo in the MRSA-invasive sublethal infection model. Macrophages activation by sublancin was found to be mediated through the TLR4 and the NF-{kappa}B and MAPK signaling pathways. Moreover, oral administration of sublancin increased the frequencies of CD4+ and CD8+ T cells in mesenteric lymph nodes. The protective activity of sublancin was associated with in vivo augmenting phagocytotic activity of peritoneal macrophages and partly improving T cell-mediated immunity. Macrophages thus represent a potentially pivotal and novel target for future development of innate defense regulator therapeutics againt S. aureus infection.

immunology↗

bioRxiv2018

Coincident binding of synthetic and natural ligands to the nuclear receptor PPARγ

Crystal structures of peroxisome proliferator-activated receptor gamma (PPAR{gamma}) have revealed overlapping binding modes for synthetic and natural/endogenous ligands, indicating competition for the orthosteric pocket. Here we show that cobinding of a synthetic ligand to the orthosteric pocket can push natural and endogenous PPAR{gamma} ligands (fatty acids) out of the orthosteric pocket towards an alternate ligand-binding site near the functionally important omega ({Omega}) loop. X-ray crystallography, NMR spectroscopy, all-atom molecular dynamics simulations, and mutagenesis coupled to quantitative functional assays reveal that synthetic ligand and fatty acid cobinding can form a \"ligand link\" to the {Omega} loop and synergistically affect the structure and function of PPAR{gamma}. These findings contribute to a growing body of evidence indicating ligand binding to nuclear receptors can be more complex than the classical one-for-one orthosteric exchange of a natural or endogenous ligand with a synthetic ligand.

biochemistry↗