一、题目：人工神经网络

报告人：马彬广 副教授

时间：1月13日晚7点

地点：档案馆4楼会议室

二、题目：Tool development and preliminary result of studying the expression divergence of homologous genes

报告人：挪威卑尔根大学 董献军 博士

时间：1月14日下午4点

地点：档案馆4楼会议室

摘要：

Increasing amount of data from comparative genomics, and newly developed technologies producing accurate gene expression data facilitate the study of the expression divergence of homologous genes. Previous studies have individually highlighted factors that contribute to the expression divergence of duplicate genes, e.g. promoter changes, exon structure heterogeneity, asymmetric histone modifications and genomic neighborhood conservation. However, there is a lack of a tool to integrate multiple factors and visualize their variety among homologous genes in a straightforward way.

In the first part, we introduce Translog (a web-based tool for Transcriptome comparison of homologous genes) that assists in the comparison of homologous genes by displaying the loci in three different views: promoter view for studying the sharing/turnover of transcription initiations, exon structure for displaying the exon-intron structure changes, and genomic neighborhood to show the macro-synteny conservation in a larger scale. CAGE data for transcription initiation are mapped for each transcript and can be used to study transcription turnover and expression changes. Alignment anchors between homologous loci can be used to define the precise homologous transcripts. We demonstrate how these views can be used to visualize the changes of homologous genes during evolution, particularly after the 2R and 3R whole genome duplication.

In the second part, I will present preliminary results about the promoter shift study, using the latest zebrafish CAGE data. It shows that 1) different type promoters can have different sequence features; 2) different promoter can be used alternatively between maternal and zygotic stages during development