Cytoscape基础教程笔记

昨天开始学用Cytoscape,其tutorial分为两个部分,基础的和高级的。基础教程又分成了四课:Getting Started、Filters & Editor、Fetching External Data和Expression Analysis。为防忘记,做个摘记。 第一课 新手上路,地址见http://goo.gl/FJLxp。 Cytoscape可以本地安装,也可以web start。软件得用java,所以要装JRE。我在Ubuntu下装了OpenJDK,可以运行。因为以前一直没把jnlp文件和java关联起来,所以从没成功web start过,试了一下“课文”里给出的链接,似乎不太靠谱,总之是没法启动。 启动Cytoscape后,得下载两个样例文件。以sif为后缀名的是蛋白相互作用网络信息,里面的蛋白以数字形式区别,以na为后缀名的是各数字id的注释,似乎两者的文件名必须相同才能关联起来。 sif文件的打开\导入有两种方式:File → Import → Network(Multiple File Types)或者直接Ctrol+L,na文件是File → Import → Node Attributes。Network导入之后有多种显示风格,2.8版默认风格下,圆圈是各蛋白,称为节点(node),其间各线为edge,代表相互作用。点中圆圈就选中了一个节点,想要多选,可以采用同时按Shift的方法,也可以先在Select → Mouse Drag Selects设置好选node还是选edge,然后鼠标拖放,一选一大片。 此外还可以有目的地选择。比如可以Select → Nodes → By Name,然后输入蛋白id,即可选中此节点。大海捞针即告完成。此操作的快捷键是Ctrl+F。 如果已经选中了节点,还可以Select → Nodes → First neighbors of selected nodes,可将所选蛋白的直接相互作用蛋白选中,再选File → New → Network → From selected nodes, all edges,即将相互作用网络的一个子网络剥离出来。 […]

Reading the NCBI’s GEO microarray SOFT files in R/BioConductor

http://www2.warwick.ac.uk/fac/sci/moac/people/students/peter_cock/r/geo/

This page discusses how to load GEO SOFT format microarray data from the Gene Expression Omnibus database (GEO) (hosted by the NCBI) into R/BioConductor. SOFT stands for Simple Omnibus Format in Text. There are actually four types of GEO SOFT file available:

GEO Platform (GPL) These files describe a particular type of microarray. They […]

RSeQC: quality control of RNA-seq experiments

Abstract

Motivation: RNA-seq has been extensively used for transcriptome study. Quality control (QC) is critical to ensure that RNA-seq data are of high quality and suitable for subsequent analyses. However, QC is a time-consuming and complex task, due to the massive size and versatile nature of RNA-seq data. Therefore, a convenient and comprehensive QC […]