BLAST Introduction to Bioinformatics Anthony Nguyen BLAST why
BLAST Introduction to Bioinformatics Anthony Nguyen
BLAST - why? ZSequence alignments provide a powerful way to compare novel sequences with previously characterized genes. ZBoth functional and evolutionary information can be inferred from well designed queries and alignments.
BLAST - what? ZBasic Local Alignment Search Tool ZBLAST provides a method for rapid searching of nucleotide and protein databases.
BLAST - how? Z The BLAST algorithm detects local as well as global alignments and regions of similarity embedded in otherwise unrelated proteins can be detected. Z Both types of similarity may provide important clues to the function of uncharacterized proteins.
BLAST - advantages Z The BLAST algorithm was written balancing speed and increased sensitivity for distant sequence relationships. Z BLAST emphasizes regions of local alignment to detect relationships among sequences which share only isolated regions of similarity.
BLAST - programs Zblastp ZCompares an amino acid query sequence against a protein sequence database.
BLAST - programs Zblastn ZCompares a nucleotide query sequence against a nucleotide sequence database.
BLAST - programs Zblastx ZCompares a nucleotide query sequence translated in all reading frames against a protein sequence database. ZThis option may be used to find potential translation products of an unknown nucleotide sequence.
BLAST - programs Ztblastn Compares a protein query sequence against a nucleotide sequence database dynamically translated in all reading frames.
BLAST - programs Ztblastx Compares the six-frame translations of a nucleotide query sequence against the six-frame translations of a nucleotide sequence database.
BLAST - objectives ZHow long is the target sequence? ZWhat is the most likely identity of the sequence? ZWhat is the source organism, where the sequence is found? ZIs the sequence is expressed?
BLAST - query ZGetting started… Zhttp: //www. ncbi. nlm. nih. gov/ ZUnknown Sequence TCGAAATAACGCGTGTTCTCAACGCGGTCGCGCAGATGCCTTT GCTCATC AGATGCGACCGCAACCACGTCCGCCGCCTTGTTCGCCGTCCC CGTGCCTC AACCACCACCACGGTGTCGTCTTCCCCGAACGCGTCCCGGTCA GCCAGCC TCCACGCGCGCGCGGAGTGCCCATTCGGGCCGCAGCT GCGACGGT GCCGCTCAGATTCTGTGTGGCAGGCGCGTGTTGGAGTCTAAA
References Zhttp: //www. geospiza. com/outreac h/BLAST/ Zhttp: //www. ncbi. nlm. nih. gov/Educ ation/BLASTinfo/information 3. html
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