序列的相似性与同源性 口相似性( (similarity): e一种直接的数量关系,比如两条序列部分相同 或相似的百分比。比如说,A序列和B序列的相 似性是80%,或者4/5 了同源性( homology): ●指从一些数据中推断出的两个基因或蛋白质序 列具而共同祖先的结论,属于质的判断 similarity→ homology Genomics and Bioinformatics 2015. TMML
Genomics and Bioinformatics 2015, TMMU 序列的相似性与同源性 相似性(similarity)： 一种直接的数量关系，比如两条序列部分相同 或相似的百分比。比如说，A序列和B序列的相 似性是80％，或者4/5。 同源性(homology)： 指从一些数据中推断出的两个基因或蛋白质序 列具而共同祖先的结论，属于质的判断 similarity homology
What is alignment? 口 Sequence alignment(序列比对 t The process of lining up two or more sequences ( dna RNa or amino acid Pairwise sequence alignment(双序列比对) 口 Multiple sequence alignment(多序列比对 Genomics and Bioinformatics 2015. TMML
Genomics and Bioinformatics 2015, TMMU What is alignment? Sequence Alignment（序列比对） The process of lining up two or more sequences (DNA, RNA or amino acid） Pairwise sequence alignment（双序列比对） Multiple sequence alignment（多序列比对）
Pairwise alignment D The process of lining up two sequences to achieve maximal levels of identity for the purpose of assessing the degree of similarity and the possibility of homology 如何自动化进行双序列比对?这是生物信息学最 基本的问题之 Genomics and Bioinformatics 2015. TMML
Genomics and Bioinformatics 2015, TMMU Pairwise alignment The process of lining up two sequences to achieve maximal levels of identity for the purpose of assessing the degree of similarity and the possibility of homology 如何自动化进行双序列比对？这是生物信息学最 基本的问题之一
Pairwise alignment o a pairwise alignment consists of a series of paired bases, one base from each sequence. There are three types of pairs C matches the same nucleotide appears in both sequences mismatches different nucleotides are found in the two sequences t gaps -a base in one sequence and a null base in the other 序列一 GCGGCCCATCAGGTAGTTGG 序列二IG maicer CCass CTGGTTGGTGTG
Genomics and Bioinformatics 2015, TMMU Pairwise alignment A pairwise alignment consists of a series of paired bases, one base from each sequence. There are three types of pairs matches = the same nucleotide appears in both sequences. mismatches = different nucleotides are found in the two sequences. gaps = a base in one sequence and a null base in the other. GCGGCCCATCAGGTAGTTGG TG-G GCGTTCCATC-- CTGGTTGGTGTG match mismatch gaps 序列一 序列二
Pairwise sequence alignment is the most fundamental operation of bioinformatics D It is used to decide if two proteins(or genes)are related structurally or functionally(同源鉴定) D It is used to identify domains or motifs that are shared between proteins(蛋白质家族) 口 It is the basis of blast searching(数据库搜索) 口 It is used in the analysis of genomes(基因组比对) Genomics and Bioinformatics 2015. TMML
Genomics and Bioinformatics 2015, TMMU Pairwise sequence alignment is the most fundamental operation of bioinformatics It is used to decide if two proteins (or genes) are related structurally or functionally (同源鉴定) It is used to identify domains or motifs that are shared between proteins (蛋白质家族) It is the basis of BLAST searching (数据库搜索) It is used in the analysis of genomes (基因组比对)