北京诺禾致源生物信息科技有限公司
12.差异基因蛋白互作网络分析
对差异分析中所产生的差异基因列表,在STRING数据库中找出这些差异基因间的互作关系,并将得到的互作数据导入 Cytoscape 软件实现互作网络的可视化。蛋白质互作数据来源于STRING数据库(http://string-db.org/)。
互作网络如下图所示,其中节点(node)的大小与此节点的度(degree)成正比,即与此节点相连的边越多,它的度越大,节点也就越大。节点的颜色与此节点的聚集系数(clustering coefficient)相关,颜色梯度由绿到红对应聚集系数的值由低到高;聚集系数表示此节点的邻接点之间的连通性好坏,聚集系数值越高表示此节点的邻接点之间的连通性越好。边(edge)的宽度表示此边连接的两个节点间的互相作用的关系强弱,互相作用的关系越强,边越宽。
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图11 差异基因互作网络图
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