Is there any method to blast in other databases in blast2go program? help!?

[hugh_hang]

I have about 300 sequences to blast and analys with blast2go.
BUT, In blast2go, I can only blast several DBs in the option list, can i add another db (like TAIR) into it and run the blast2go? OR can some other applications both online or offline create a blast result which can be imported into blast2go?

Thanks a lot!

[kmcarr]

The default configuration for online BLAST through the Blast2GO GUI application uses the NCBI QBlast service which provides only those databases listed; you can not add custom databases to this method.

Your alternatives to use different databases are:

1) Set up your own WWW-BLAST service (or find access to someone's who will share) which has or can be customized with the databases you want. Edit the blast2go.properties file on your local computer to designate this WWW-BLAST server as the default source for running your online BLAST searches through the Blast2GO GUI.

2) Run your BLAST search using a standalone (command line) BLAST installation against your custom database. Be sure to configure your BLAST search to output the results in XML format. Launch Blast2GO and load your FASTA sequence file as normal. From the File menu select "Import->Import Blast Results". Select your XML file (or files) for import. Once the BLAST results have been imported proceed with Mapping and Annotation as usual.

I recommend option #2 because it is easier and more scalable.

[hugh_hang]

The default configuration for online BLAST through the Blast2GO GUI application uses the NCBI QBlast service which provides only those databases listed; you can not add custom databases to this method.

Your alternatives to use different databases are:

1) Set up your own WWW-BLAST service (or find access to someone's who will share) which has or can be customized with the databases you want. Edit the blast2go.properties file on your local computer to designate this WWW-BLAST server as the default source for running your online BLAST searches through the Blast2GO GUI.

2) Run your BLAST search using a standalone (command line) BLAST installation against your custom database. Be sure to configure your BLAST search to output the results in XML format. Launch Blast2GO and load your FASTA sequence file as normal. From the File menu select "Import->Import Blast Results". Select your XML file (or files) for import. Once the BLAST results have been imported proceed with Mapping and Annotation as usual.

I recommend option #2 because it is easier and more scalable.

Thank you, I have thought of the option #2, but how can I get the database downloaded from TAIR in the format of .fasta with accession No. like AT4G22340

[chadn737]

Here is the ftp site for the TAIR10 blast sets. You probably want one of the cds or cDNA files:

ftp://ftp.arabidopsis.org/home/tair/...R10_blastsets/

[hugh_hang]

Here is the ftp site for the TAIR10 blast sets. You probably want one of the cds or cDNA files:

ftp://ftp.arabidopsis.org/home/tair/...R10_blastsets/

Thank you, I tried clicking "download" in the TAIR website, but I'm really confused by its dendroid file structure.

[kmcarr]

Originally Posted by chadn737
Here is the ftp site for the TAIR10 blast sets. You probably want one of the cds or cDNA files:

ftp://ftp.arabidopsis.org/home/tair/...R10_blastsets/

Thank you, I tried clicking "download" in the TAIR website, but I'm really confused by its dendroid file structure.

Just click on the link chadn provided in his reply. It will take you directly to the correct FTP directory with various FASTA files. Read the Readme_blastdatasets_TAIR10.txt file for a description of what each one is.

I, myself would choose the "TAIR10_pep_20110103_representative_gene_model_updated" (or "TAIR10_pep_20101214_updated") and assuming you are BLASTing with nucleotide queries run BLASTX against this protein dataset.

[hugh_hang]

Just click on the link chadn provided in his reply. It will take you directly to the correct FTP directory with various FASTA files. Read the Readme_blastdatasets_TAIR10.txt file for a description of what each one is.

I, myself would choose the "TAIR10_pep_20110103_representative_gene_model_updated" (or "TAIR10_pep_20101214_updated") and assuming you are BLASTing with nucleotide queries run BLASTX against this protein dataset.

My sequences are cDNA-AFLP results, does that mean "TAIR10_cdna_..." is a better option? By the way, what does the "pep" in "TAIR10_pep_..." mean?

[hugh_hang]

The default configuration for online BLAST through the Blast2GO GUI application uses the NCBI QBlast service which provides only those databases listed; you can not add custom databases to this method.

Your alternatives to use different databases are:

1) Set up your own WWW-BLAST service (or find access to someone's who will share) which has or can be customized with the databases you want. Edit the blast2go.properties file on your local computer to designate this WWW-BLAST server as the default source for running your online BLAST searches through the Blast2GO GUI.

2) Run your BLAST search using a standalone (command line) BLAST installation against your custom database. Be sure to configure your BLAST search to output the results in XML format. Launch Blast2GO and load your FASTA sequence file as normal. From the File menu select "Import->Import Blast Results". Select your XML file (or files) for import. Once the BLAST results have been imported proceed with Mapping and Annotation as usual.

I recommend option #2 because it is easier and more scalable.

Sir, I've done what you recommanded me to do. But after I imported the XML file, the mapping and annotation seems not recognise the blast result and give 0 sequences mapped or annotated, my database id from TAIR10_blast_set which are nucleotide queries fasta files.

[kmcarr]

My sequences are cDNA-AFLP results, does that mean "TAIR10_cdna_..." is a better option? By the way, what does the "pep" in "TAIR10_pep_..." mean?

cDNA-AFLP you say? O.K.

"pep" = peptide, meaning that these FASTA files contain the protein (amino acid) sequence translated from the predicted CDS.

Given the method used to isolate your material for sequencing can be assumed that the sequences are derived from protein coding genes. Amino acid sequence is more conserved than the underlying nucleic acid sequence so comparing across species using amino acid sequences is more sensitive than comparisons based on DNA sequence. This is why I suggested using the Arabidopsis protein (TAIR10_pep_*) database as a target in a BLASTX search with your cDNA query sequences. BLASTX will translate your query sequences in all 6 possible reading frames and compare those amino acid sequences for similarity.

[kmcarr]

Sir, I've done what you recommanded me to do. But after I imported the XML file, the mapping and annotation seems not recognise the blast result and give 0 sequences mapped or annotated, my database id from TAIR10_blast_set which are nucleotide queries fasta files.

Are you sure the output from the BLAST search is properly formatted and contains valid hits?

[hugh_hang]

cDNA-AFLP you say? O.K.

"pep" = peptide, meaning that these FASTA files contain the protein (amino acid) sequence translated from the predicted CDS.

Given the method used to isolate your material for sequencing can be assumed that the sequences are derived from protein coding genes. Amino acid sequence is more conserved than the underlying nucleic acid sequence so comparing across species using amino acid sequences is more sensitive than comparisons based on DNA sequence. This is why I suggested using the Arabidopsis protein (TAIR10_pep_*) database as a target in a BLASTX search with your cDNA query sequences. BLASTX will translate your query sequences in all 6 possible reading frames and compare those amino acid sequences for similarity.

I see. Thank you.

[hugh_hang]

Are you sure the output from the BLAST search is properly formatted and contains valid hits?

I cleared the unproper tabs(\t) & enters(\r\n) and it still doesn't work. I have to doubt if it's because there are too fewer sequences that have found hits or if I should use protain DBs instead of nucleotide ones.

[kmcarr]

I cleared the unproper tabs(\t) & enters(\r\n) and it still doesn't work. I have to doubt if it's because there are too fewer sequences that have found hits or if I should use protain DBs instead of nucleotide ones.

What made you think that there were improper tabs or returns that needed removing?

Please post an example of the BLAST output before you edited it (just a couple of dozen lines is enough).

[hugh_hang]

What made you think that there were improper tabs or returns that needed removing?

Please post an example of the BLAST output before you edited it (just a couple of dozen lines is enough).

********************
<BlastOutput_param>
<Parameters>
<Parameters_matrix>BLOSUM62</Parameters_matrix>
<Parameters_expect>1e-06</Parameters_expect>
<Parameters_gap-open>11</Parameters_gap-open>
<Parameters_gap-extend>1</Parameters_gap-extend>
<Parameters_filter>L;</Parameters_filter>
</Parameters>
</BlastOutput_param>
********************
this is what blast2go formatted and that below is what local blast formatted.
********************
<BlastOutput_param>
____<Parameters>
________<Parameters_expect>1e-06</Parameters_expect>
________<Parameters_gap-open>11</Parameters_gap-open>
________<Parameters_gap-extend>1</Parameters_gap-extend>
________<Parameters_filter>L;</Parameters_filter>
____</Parameters>
</BlastOutput_param>
********************
("_" stands for space)
additionally, blast2go uses newline(\n) to switch line and my local blast program in windows uses return & newline(\r\n), which I suspect to impact.

[upendra_35]

I got the same problem. When i tried to import the xml file that was blatsted against Arabidopsis TAIR10 cDNA reference, the mapping and annotation steps failed in blast2go software. So i guess it is something to do with the format of xml file generated using "nr" database and "TAIR10" database.
Does anybody know a way to modify this xml file so that i can import to blast2go?

Thanks
Upendra