Alpha-picolinic acid,a fungal toxin and mammal apoptosis-inducing agent,elicits hypersensitive-like response and enhances disease resistance in rice

Alpha-picolinic acid (PA),a metabolite of tryptophan and an inducer of apoptosis in the animal cell,has been reported to be a toxin produced by some of plant fungal pathogens and used in screening for disease resistant mutants. Here,we report that PA is an efficient apoptosis agent triggering cell death of hypersensitive-like response in planta. Confirmed by Fluorescence Activated Cell Sorter (FACS),rice suspension cells and leaves exhibited programmed cell death induced by PA. The PA-induced cell death was associated with the accumulation of reactive oxygen species that could be blocked by diphenylene iodonium chloride,indicating that the generation of reactive oxygen species was NADPHoxidase dependent. We also demonstrated the induction of rice defense-related genes and subsequent resistant enhancement by PA against the rice blast fungus Magnaporthe grisea. Hence,it was concluded that the PA-stimulated defense response likely involves the onset of the hypersensitive response in rice,which also provides a simple eliciting tool for studying apoptosis in the plant cell.

microRNAs regulation and its role as biomarkers in diseases

MicroRNAs （miRNAs）, approximately 21 to 23 nucleotides （nt） in length, belong to a set of smal non-coding RNA molecules that were not thought to be functional until the recent decades. miRNAs play important roles in many diseases such as various kinds of cancers and immune disorders. Many studies have focused on the relationship between miRNAs and diseases. miRNAs are significant mediators in human growth and development and in the genesis and development of diseases. Almost 30% of the activity of protein-coding genes is forecasted to be regulated by miRNAs in mammals, and some miRNAs are regarded as potential therapeutic targets for various diseases. In this review, we outline some functions of miRNAs, especialy those related to diseases.

Wntl-regu｜ated genetic networks in midbrain dopaminergic neuron development

Neurons synthesizing the neurotransmitter dopamine exert crucial functions in the mammalian brain. The biggest and most important population of dopamine-synthesizing neurons is located in the mammalian ventral midbrain （VM）, and controls and modulates the exe- cution of motor, cognitive, affective, motivational, and rewarding behaviours. Degeneration of these neurons leads to motor deficits that are characteristic of Parkinson＇s disease, while their dysfunction is involved in the pathogenesis of psychiatric disorders including schizophrenia and addiction. Because the aetiology and therapeutic prospects for these diseases include neurodevelopmental aspects, substantial scientific interest has been focused on deciphering the mechanistic pathways that control the generation and sur- vival of these neurons during embryonic development. Researches during the last decade revealed the pivotal role of the secreted Wntl ligand and its signaUing cascade in the generation of the dopamine-synthesizing neurons in the mammalian VM. Here, we summarize the initial and more recent findings that have unravelled several Wntl-controUed genetic networks required for the proliferation and commitment of VM progenitors to the dopaminergic cell fate during midgestational embryonic stages, and for the correct differentiation of these progenitors into postmitotic dopamine-synthesizing neurons at late midgestational embryonic and foetal stages.

Large-scale study of long non-coding RNA functions based on structure and expression features

Mammals and other complex organisms can transcribe an abundance of long non-coding RNAs(lncRNAs)that fulfill a wide variety of regulatory roles in many biological processes.These roles,including as scaffolds and as guides for protein-coding genes,mainly depend on the structure and expression level of lncRNAs.In this review,we focus on the current methods for analyzing lncRNA structure and expression,which is basic but necessary information for in-depth,large-scale analysis of lncRNA functions.

TiO_2-functionalized mesoporous materials for sensitive analysis of multi-phosphopeptides

Protein phosphorylation as one of the most important post-translational modifications in mammalian cells regulates numerous biological processes. Here we propose a novel strategy for the selective isolation and sensitive analysis of mul- ti-phosphopeptides based on TiO2-gratfed mesoporous materials, in which MCM-41 and SBA-15 were chosen as the hard templates. The commercialized IMAC and TiO2 nanopartices were further investigated in the phosphopeptide analysis for comparison. The enrichment efficiency was evaluated and measured by MALDI-TOF mass spectrometry. The results indicated that both TiO2-SBA-15 and TiO2-MCM-41 exhibited the preferential affinity to multi-phosphopeptides compared with the other two widely used strategies. The mesoporous TiO2 based protocol showed highly selective and sensitive properties, where phosphopepddes could be identified at femtomole.