1 / 17

Public Resources (II) – Analysis tools

Public Resources (II) – Analysis tools. Web-based analysis tools – easy to use, but often with less customization options. Stand-alone analysis tools – requires installation and configuration, but provides more customizatio0n options. Commercial analysis tools

mickey
Télécharger la présentation

Public Resources (II) – Analysis tools

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Public Resources (II) – Analysis tools • Web-based analysis tools – easy to use, but often with less customization options. • Stand-alone analysis tools – requires installation and configuration, but provides more customizatio0n options. • Commercial analysis tools • Scripting for bioinformatics projects

  2. Stand-alone tools 1. Rules of the thumb: • Make a folder for each program. • Make a sub-folder for input/output if necessary. • Link GUI-based .exe application to program menu

  3. Stand-alone tools 2. Practice –the ClustalX application. Download the zip file to the GMS6014 folder. Unzip the files to a folder named “clustalx”. Edit the 3TNF file with WordPad and save. Activate the .exe file. Load sequence file, select sequences, perform alignment. Write the alignment to a ps file.

  4. Stand-alone tools 3. Command line applications: • Accounts for a large number of high-quality, sophisticated programs. Practice – (install and) run standalone blast in your own computer

  5. Pet Projects: Identifying the ortholog of TNF (Tumor necrosis factor) in mosquito genomes

  6. Download the BLAST executable file, save the file in a folder, such as c:\GMS6014\blast\ • Run the installation program by double click. Inspect the folder following installation. • Add three more folders to your /blast directory, “/query”, “/dbs”, and “/out”. Practice – Install the blast program (1)

  7. Inspect the contents of the doc, data, and bin folder. Move the programs from blast\bin to the blast folder. • Bring a command (cmd) window by typing “cmd” in the StartRun box. • Go to the blast folder by typing “cd C:\GMS6014\blast” • Try to run the program by typing “blastall”, read the output. Practice – Install the blast program (2)

  8. Download data file from the course web page, or Ensemble. Save in the blast\dbs folder. • Start a CMD window, navigate to the C:\GMS6014\blast folder. • At the prompt “C:\GMS6014\blast >” type the command “formatdb –i dbs\Aedes –p F” -- format the dataset for the program. • Compose the query sequence save as “3TNF.txt” in the “blast\query\” folder. • Initiated the search by typing “blastall –p tblastn –d dbs\Aedes –query query\3TNF.txt –o out\3TNF_Aedes.html –T T” Practice -- BLAST search in your own computer

  9. Program – format database for search. What’s in a command? formatdb –i dbs\Aedes –p F Tell me is it a protein sequence file? Feed me the input file name For more info, refer to the “user manual” file in the blast\doc folder.

  10. Do it at any time, no waiting on the line. • Search for multiple sequences at once. • Search a defined data set. • Automate Blast analysis. • Combine Blast with other analysis. • ….. Advantages of Running BLAST at Your Own Machine

  11. BLAST is a program implemented in C/C++ void BlastTickProc(Int4 sequence_number, BlastThrInfoPtr thr_info) { if(thr_info->tick_callback && (sequence_number > (thr_info->last_db_seq + thr_info->db_incr))) { NlmMutexLockEx(&thr_info->callback_mutex); thr_info->last_db_seq += thr_info->db_incr; thr_info->tick_callback(sequence_number, thr_info->number_of_pos_hits); thr_info->last_tick = Nlm_GetSecs(); NlmMutexUnlock(thr_info->callback_mutex); } return; } /* Sends out a message every PERIOD (i.e., 60 secs.) for the index. THis function runs as a separate thread and only runs on a threaded platform. Should I care ?

  12. char: name char: sequence SEQ If you care: 1.) Data structure and Algorithm Identify the best alignment for two sequences (p69-73) int: seq_length Seq1: MA-DSV—WC.. Seq2: MALD-IHWS..

  13. Programming language comparison Translation : Python Translation : C /* TRANSLATION: 3 or 6 frame translate cDNA sequences */ //--------------------------------------------------------------------------- #include "translation.hpp" int main(int argc, char **argv) { int num_seq=0; char string[MAXLINE]; DSEQ * dseq; infile.getline (string,MAXLINE); if (string[0]=='>') strncpy (dbname,string,MAXLINE); while (!infile.eof()) { dseq=Get_Lib_Seq (); if (dseq->reverse==0) Translation (&dseq->name[1], dseq->seq); else Translation (&dseq->name[1], dseq->r_seq); num_seq++; if (num_seq%1000==0) { cout<<num_seq<<endl; cout<<dseq->name<<endl; } delete dseq; } infile.close(); outfile.close(); cout<<num_seq<<" translated"<<endl; getch(); return 0; } DSEQ* Get_Lib_Seq() { int i,n; char str[MAXLINE]; DSEQ* dseq; n = 0; dseq=new DSEQ; strcpy (dseq->name, dbname); while(infile.getline(str,MAXLINE)) { if (str[0] == '>') { strcpy( dbname, str); break; } for(i=0;i<strlen(str);i++) { if(n==MAXSEQ) break; dseq->seq[n++] = str[i]; } } dseq->seq[n]='\0'; if(n==MAXSEQ) cout<<"WARNING: sequence"<<dbname<<"too long!"<<endl; dseq->len=n; if (dseq->name[9]=='3') Reverse (dseq); else dseq->reverse=0; return dseq; } void Reverse (DSEQ* dseq) //Reverse dseq { int i,j; j=0; for (i=(dseq->len-1);i>0;i--) { if (dseq->seq[i]=='A'||dseq->seq[i]=='a') dseq->r_seq[j++]='T'; if (dseq->seq[i]=='C'||dseq->seq[i]=='c') dseq->r_seq[j++]='G'; if (dseq->seq[i]=='G'||dseq->seq[i]=='g') dseq->r_seq[j++]='C'; if (dseq->seq[i]=='T'||dseq->seq[i]=='t') dseq->r_seq[j++]='A'; if (dseq->seq[i]=='N'||dseq->seq[i]=='n') dseq->r_seq[j++]='N'; } dseq->r_seq[j++]='\0'; dseq->reverse=1; } void Translation (char name[], char seq[]) { char ppseq[MAXSEQ/3]; for (int f=0; f<3; f++) { outfile<<">"<<"F_"<<f<<name<<endl; int j=0; int len=strlen(seq); for( int i=f; i<len; i=i+3) ppseq[j++]=Translate(&seq[i]); ppseq[j++]='\0'; int m=strlen(ppseq)/50; // output 50 aa per line for (int n=0; n<=m; n++) { for (int i=n*50; i<50*(n+1); i++) { outfile<<ppseq[i]; if (ppseq[i]=='\0') break; } outfile<<endl; } } } char Translate(char s[]) { int c1,c2,c3; char P, code[3]; //***standard translation table, A(0),C(1), G(2), T(3)***** char table [4][4][4]= {{{'K','N','K','N'},{'T','T','T','T'},{'R','S','R','S'},{'I','I','M','I'}}, {{'Q','H','Q','H'},{'P','P','P','P'},{'R','R','R','R'},{'L','L','L','L'}}, {{'E','D','E','D'},{'A','A','A','A'},{'G','G','G','G'},{'V','V','V','V'}}, {{'*','Y','*','Y'},{'S','S','S','S'},{'*','C','W','C'},{'L','F','L','F'}}}; //*********** table2 for n at 3rd position******************** char table2 [4][4]={{'X','T','X','X'},{'X','P','R','L'}, {'X','A','G','V'},{'X','S','X','X'}}; strncpy (code, s, 3); c1=Convert(code[0]); c2=Convert(code[1]); c3=Convert(code[2]); if (c1>=4 || c2>=4) P='X'; //can be Optimized further here by considering.... else { if (c3>=4) P=table2[c1][c2]; else P=table[c1][c2][c3]; //P=table[Convert(code[0])][Convert(code[1])][Convert(code[2])]; } return (P); } int Convert (char c) { char s=c; if (s=='A'||s=='a') return (0); if (s=='C'||s=='c') return (1); if (s=='G'||s=='g') return (2); if (s=='T'||s=='t'||s=='U'||s=='u') return (3); if (s=='N'||s=='n') return (4); else return (5); } f#Translation -- read from fasta DNA file and translate into three frames # import string from Bio import Fasta from Bio.Tools import Translate from Bio.Alphabet import IUPAC from Bio.Seq import Seq ifile = "S:\\Seq\\test.fasta" parser = Fasta.RecordParser() file =open (ifile) iterator = Fasta.Iterator (file, parser) cur_rec = iterator.next() cur_seq = Seq (cur_rec.sequence,IUPACUnambiguousDNA()) translator = Translate.unambiguous_dna_by_id[1] translator.translate (cur_seq)

  14. Programming languages Efficiency, Power Simplicity, Fast Dev. C/C++ Perl - Bioperl Java - Biojava Python - Biopython

  15. Observe: scripting is not that difficult Example: Python and bioPython. • Simple python scripts. • Batch Blast with a Python script.

  16. Blast output

  17. Questions: • Is this a expressed gene in the Aedes mosquito? • - Gene prediction & gene structure • Is this the true ortholog of TNF? • - Fundamentals of sequence comparison • What can we learn from the comparison of sequences? • -- protein dommains/motifs. Questions after the Blast search?

More Related