Expression in Arabidopsis of a Strawberry Linalool Synthase Gene Under the Control of the Inducible Potato PI2 Promoter

To investigate the role of inducible linalool in Arabidopsis-insect interactions, the FANES 1 linalool synthase （LIS） cDNA from strawberry with plastid targeting and a synthetic intron （LIS＇） was placed under the control of the wound inducible proteinase inhibitor 2 （PI2） promoter from potato. The construct pBin-PPi2-LIS＇ was transformed to Arabidopsis thaliana ecotype Columbia 0. Kanamycin resistant TO seedlings were confirmed for the presence and transcription of the LIS＇ gene by PCR analysis on genomic DNA and by RT-PCR analysis on RNA. Genomic and RT-PCR products were sequenced to confirm correct splicing of the synthetic intron. The expression of active linalool synthase by the PPI2-LIS＇ gene construct in the transgenic lines was assessed by measuring linalool emission using solid phase micro-extraction （SPME） GC-MS measurements after induction with methyl jasmonate. Among 30 tested independent T2 transgenic lines, 10 exhibited linalool production. Linalool expression could be induced by methyl jasmonate treatment, but not by diamondback moth larvae.

Regulated Gene Expression with Promoters Responding to Inducers

Genetically engineered transgenic animals and plants have proven to be extremely useful for analyzing biochemical and developmental processes.Promoters responding to chemical inducers will be powerful tools for basic research in molecular biology and biotechnological applications.Various chemical inducible systems based on activation and inactivation of the target gene had been described.The transfer of regulatory elements from prokaryotes,insects,and mammals has opened new avenues to construct chemically inducible promoters that differ in their ability to regulate the temporal and spatial expression patterns,and this will dramatically increase the application of transgenic technology.This review provides an overview on regulation of gene expression,promoter activating systems,promoter inactivation systems,inducible gene over expression,and inducible anti suppression.

Unstable evolution of railway slope under the rainfall-vibration joint action

Understanding the unstable evolution of railway slopes is the premise for preventing slope failure and ensuring the safe operation of trains.However,as two major factors affecting the stability of railway slopes,few scholars have explored the unstable evolution of railway slopes under the joint action of rainfall-vibration.Based on the model test of sandy soil slope,the unstable evolution process of slope under locomotive vibration,rainfall,and rainfall-vibration joint action conditions was simulated in this paper.By comparing and analyzing the variation trends of soil pressure and water content of slope under these conditions,the change laws of pore pressure under the influence of vibration and rainfall were explored.The main control factors affecting the stability of slope structure under the joint action conditions were further defined.Combined with the slope failure phenomena under these three conditions,the causes of slope instability resulting from each leading factor were clarified.Finally,according to the above conclusions,the unstable evolution of the slope under the rainfall-vibration joint action was determined.The test results show that the unstable evolution process of sandy soil slope,under the rainfall-vibration joint action,can be divided into:rainfall erosion cracking,vibration promotion penetrating,and slope instability sliding three stages.In the process of slope unstable evolution,rainfall and vibration play the roles of inducing and promoting slide respectively.In addition,the deep cracks,which are the premise for the formation of the sliding surface,and the violent irregular fluctuation of soil pressure,which reflects the near penetration of the sliding surface,constitute the instability characteristics of the railway slope together.This paper reveals the unstable evolution of sandy soil slopes under the joint action of rainfall-vibration,hoping to provide the theoretical basis for the early warning and prevention technology of railway slopes.

Interleukin-13 promotes cellular senescence through inducing mitochondrial dysfunction in IgG4-related sialadenitis

Immunoglobulin G4-related sialadenitis(IgG4-RS)is an immune-mediated fibro-inflammatory disease and the pathogenesis is still not fully understood.The aim of this study was to explore the role and mechanism of interleukin-13(IL-13)in the cellular senescence during the progress of IgG4-RS.We found that the expression of IL-13 and IL-13 receptorα1(IL-13Rα1)as well as the number of senescent cells were significantly higher in the submandibular glands(SMGs)of IgG4-RS patients.IL-13 directly induced senescence as shown by the elevated activity of senescence-associatedβ-galactosidase(SA-β-gal),the decreased cell proliferation,and the upregulation of senescence markers(p53 and p16)and senescence-associated secretory phenotype(SASP)factors(IL-1βand IL-6)in SMG-C6 cells.Mechanistically,IL-13 increased the level of phosphorylated signal transducer and activator of transcription 6(p-STAT6)and mitochondrial-reactive oxygen species(mt ROS),while decreased the mitochondrial membrane potential,ATP level,and the expression and activity of superoxide dismutase 2(SOD2).Notably,the IL-13-induced cellular senescence and mitochondrial dysfunction could be inhibited by pretreatment with either STAT6 inhibitor AS1517499 or mitochondria-targeted ROS scavenger Mito TEMPO.Moreover,IL-13 increased the interaction between p-STAT6 and c AMP-response element binding protein(CREB)-binding protein(CBP)and decreased the transcriptional activity of CREB on SOD2.Taken together,our findings revealed a critical role of IL-13 in the induction of salivary gland epithelial cell senescence through the elevated mitochondrial oxidative stress in a STAT6–CREB–SOD2-dependent pathway in IgG4-RS.

Cystatin C Induces Insulin Resistance in Hippocampal Neurons and Promotes Cognitive Dysfunction in Rodents

Dear Editor,Cognitive impairment is a hallmark of neurodegenerative disorders such as Alzheimer’s disease（AD）and Parkinson’s disease.Growing evidence has demonstrated that cognitive impairment is closely associated with insulin resistance.