URL PHONE FAX ADDRESS #909, VENTURE VALLEY, 958, GOSAEK-DONG, GWONSEON-GU,SUWON, GYEONGGI-DO, KOREA Copyright ⓒ Insilicogen, Inc All rights reserved. Tutorial: Expression analysis part Ⅰ ~ Ⅳ 2009 – 김 경 의
Importing array data NCBI Gene Expression Omnibus(GEO) database 에서 data set download : &targ=gsm&form=text&view=data 데이터 다운로드 후 원하는 디렉토리에 저장하고 Toolbar 에서 파일을 Import 한다. ^SAMPLE = GSM #ID_REF = #VALUE = GCOS signal #ABS_CALL = Present/absent per Affy software !sample_table_begin ID_REFVALUEABS_CALL
Import Annotation file Affymetrix web site: RAE230A 를 검색하여 annotation file 을 다운로드합니다.
Grouping the samples Toolbox | Expression Analysis | Set up Experiment
Defining the number of groups
Naming the groups
Assigning the samples to groups First 6 samples right-click and select Heart, Select the last 6 samples, right-click and select Diaphragm
The experiment table
Annotation level
Transformation Toolbox | Expression Analysis | General Plots | Create MA Plot
MA plot before transformation M : log-intensity ratio =log ₂ R - log ₂ G A : mean log-intensity = (log ₂ R + log ₂ G)/2 M 과 A 값을 이용한 Plotting 은 위의 log ₂ R 과 log ₂ G 를 이용한 plot 을 45° 회전시킨 plot 으로 0 값 을 기준선으로 gene data 를 관찰
Transformation Toolbox | Expression Analysis | Transformation and Normalization | Transform
MA plot after transformation
Comparing spread and distribution Toolbox | Expression Analysis | Quality Control | Create Box Plot
Box plot of the 12samples in the experiment
Group differentiation Toolbox | Expression Analysis | Quality Control | Principal Component Analysis
Principal component analysis colored by group
Naming the outlier Dot properties | select GSM in the drop-down box | Show names
Hierarchicla clustering Toolbox | Expression Analysis | Quality Control | Hierarchical Clustering of Samples Leave the parameters at their default and click Finish
Sample clustering
Statistical analysis Toolbox | Expression Analysis | Statistical Analysis | Statistical Analysis
Statistical analysis
FDR p-values compared to Bonferroni-corrected p-values
Filtering on FDR p-values
Inspecting the volcano plot Ctrl key 를 누르고 volcano plot 을 누르면 두개의 view 가 나타난다. 선택 된 데이터에 대해서는 dot 이 붉은색으로 표현된다.
Filtering absent/present calls and fold change Add search criterion (+) button 을 누르면 criteria 를 추가할 수 있다. Filtering genes where at least 5 out of 6 calls in each group are present. The absolute value of group mean difference should be larger than 2
Saving the gene list
New experiment Save
Processes that are over-represented in the small list Toolbox | Expression Analysis | Annotation Test | Hypergeometric Tests on Annotations
The result of testing on GO biological process
Gene Set Enrichment Analysis (GSEA) Toolbox | Expression Analysis | Annotation Test | Gene Set Enrichment Analysis(GSEA) Original full experiment select
Gene set enrichment analysis based on GO biological process
The result of a gene set enrichment analysis based on GO biological process
Add Array Annotations Toolbox | Annotations test | Add Array Annotations
Download Sequence Select 한 개수 만큼 sequence 를 download 할 수 있습니다.
Created sequence 선택한 개수만큼 sequence 생성
Saving sequence Sequence name 을 하나씩 드래그하여 Navigation Area 에 저장합니다.
BLAST Search Toolbox | BLAST Search | NCBI BLAST 방금 저장한 sequence 를 선택 3 개의 sequence 를 한번에 BLAST Search 할 수 있음
Choose program and database
BLAST Search result