浅谈“沉默生”的转化教育

1事件描述与＂沉默生＂的转化过程班主任在接手一个新班级时首先要做的就是认识学生,而在认识的过程中,有一部分学生群体是不容忽视的,那就是＂沉默生＂。他们面对老师时常常是沉默的;走进教室往往会选择最不起眼的位子;不会主动要求参加活动;大多时候只是待在原地等待别人的要求和引领……但是，

Biochemical mechanisms of the RNA-induced silencing complex

In less than 10 years since its inception, RNA interference （RNAi） has had extraordinary impact on biomedical science. RNAi has been demonstrated to influence numerous biological and disease pathways. Development and adoption of RNAi technologies have been prolific ranging from basic loss-of-function tools, genome-wide screening libraries to pharmaceutical target validation and therapeutic development. However, understanding of the molecular mechanisms of RNAi is far from complete. The purpose of this brief review is to highlight key achievements in elucidating the bio- chemical mechanisms of the RNA-induced silencing complex and to outline major challenges for the field.

Progress of research in miR-218 and cervical cancer

MicroRNAs （miRNAs） are small endogenous non-coding RNAs which can specifically silence gene expression, and thereby alter cell and organism phenotype. Deregulation of miRNA expression has been discovered in a variety of tumors and it is now clear that they contribute to cancer development and progression. Previous studies have indicated that miRNAs are involved in developmental timing, cell proliferation, apoptosis, morphogenesis [1], antiviral defense 121, and tumorigenesis [3]. In cancer pathways, altered expression of tumor suppressive or oncogenic miRNAs can disrupt regulatory mechanisms normal. Altered miRNAs expression patterns have been observed in a variety of diseased tissues. Cervical cancer is the most common malignant tumor in female reproductive tract. Recently more and more study showed a large number of miRNAs were down-regulated or up-regulated in cervical cancer. Recent data revealed that miRNA-218 （miR-218） played important roles in tumor initiation and development. This review focuses on analysis of miR-218 and will provide some insight into the progress of cervical cancer.

Study on Inhibitionof Growth of ACHN Cells via shRNA Expression Vector-Mediated Cycline1 Gene Silencing

OBJECTIVE To explore the inhibition of ACHN cells via shRNAexpression vector mediated cyclinE1 gene silencing.METHODS The shRNA targeting at cyclinE1 gene was designedand synthesized. By ligation, the fragment was inserted intopGenesil-1-U6 to construct the recombinant plasmid pGenesil-1-U6-cyclinE1. The identified recombinant plasmid was introducedinto ACHN cells with lipofectamine 2000. The inhibition ofcyclinE1 mRNA and protein expression were analyzed by RT-PCRand western-blotting. MTT method was used for observing cellproliferation and drawing growth curve. The cell cycle and ratiosof apoptotic cell were assessed by flow cytometric detection. Theability of invasion and speed of cell migration were detected bytranswell chamber invasive models and cell scratch method.RESULTS The inhibition of expression of cyclinE1 in ACHN cellsmediated by recombinant vector (0.0933 ± 0.05) was significantlylower than that in the group of transfected with empty vector(0.8827 ± 0.04) and the control group (0.9021 ± 0.03) (P < 0.05).Flow cytometry showed that recombinant cells were blocked inthe G_1 phase and the apoptotic ratio was increased significantly(11.15 ± 4.00)% (P < 0.05). The curves of cell growth indicated thatthe proliferation of cell transfected with recombinant plasmid wasinhibited significantly compared with that in control group (P <0.05). The results of transwell and cell scratch suggested that theabilities of invasion and migration of the cells transfected withrecombinant plasmid were decreased conspicuously (P < 0.05).CONCLUSION The expression of cyclinE1 could be inhibitedsuccessfully by RNA interference induced by shRNA expressionvector. This consequently inhibits the cell growth and inducesapoptosis. Our study provided a preliminary result in searching ofRNA interference (RNAi) therapy for renal cell carcinoma.

Virus-induced gene silencing and its application in plant functional genomics

Virus-induced gene silencing is regarded as a powerful and efficient tool for the analysis of gene function in plants because it is simple, rapid and transformation-free. It has been used to perform both forward and reverse genetics to identify plant functional genes. Many viruses have been developed into virus-induced gene silencing vectors and gene functions involved in development, biotic and abiotic stresses, metabolism, and cellular signaling have been reported. In this review, we discuss the development and application of virus-induced gene silencing in plant functional genomics.