Skip to main content
Ch. 18 - Genomics, Bioinformatics, and Proteomics
Klug - Essentials of Genetics 10th Edition
Klug10th EditionEssentials of GeneticsISBN: 9780135588789Non è quello che usi tu?Cambia libro di testo
Capitolo 18, Problema 8

BLAST searches and related applications are essential for analyzing gene and protein sequences. Define BLAST, describe basic features of this bioinformatics tool, and give an example of information provided by a BLAST search.

Guida verificata passo dopo passo
1
Step 1: Define BLAST by explaining that it stands for Basic Local Alignment Search Tool, which is a bioinformatics algorithm used to compare an input nucleotide or protein sequence against a database of sequences to find regions of similarity.
Step 2: Describe the basic features of BLAST, including its ability to quickly identify local alignments rather than global alignments, its use of scoring matrices to evaluate sequence similarity, and its statistical framework to assess the significance of matches.
Step 3: Explain that BLAST can be used for different types of searches such as nucleotide-to-nucleotide (blastn), protein-to-protein (blastp), and translated searches (blastx), depending on the input and database sequences.
Step 4: Discuss how BLAST outputs include important information such as the alignment score, E-value (expectation value) which indicates the likelihood of the match occurring by chance, and the identity percentage showing how similar the sequences are.
Step 5: Provide an example of information from a BLAST search, such as identifying a gene in an unknown DNA sequence by finding a highly similar known gene in the database, or predicting the function of a protein by comparing it to proteins with known functions.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
54s

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

BLAST (Basic Local Alignment Search Tool)

BLAST is a bioinformatics algorithm used to compare an input nucleotide or protein sequence against a database to find regions of local similarity. It helps identify homologous sequences, infer functional and evolutionary relationships, and locate conserved domains.
Video consigliato:

Features of BLAST

BLAST performs rapid sequence alignments by breaking sequences into smaller words and extending matches to find high-scoring segment pairs. It provides statistical significance scores (E-values), alignment scores, and identifies similar sequences with varying degrees of identity and coverage.
Video consigliato:

Information Provided by a BLAST Search

A BLAST search outputs aligned sequences with similarity scores, E-values indicating match significance, and annotations such as gene or protein names. For example, it can reveal potential functions of an unknown gene by matching it to known genes in the database.
Video consigliato:
Pratica correlata
Domanda del libro di testo

Describe the human genome in terms of genome size, the percentage of the genome that codes for proteins, how much is composed of repetitive sequences, and how many genes it contains. Describe two other features of the human genome.

623
views
Domanda del libro di testo

Annotation involves identifying genes and gene-regulatory sequences in a genome. List and describe characteristics of a genome that are hallmarks for identifying genes in an unknown sequence. What characteristics would you look for in a bacterial genome? A eukaryotic genome?

847
views
Domanda del libro di testo

What is bioinformatics, and why is this discipline essential for studying genomes? Provide two examples of bioinformatics applications.

641
views
Domanda del libro di testo

Describe three major goals of the Human Genome Project.

852
views
Domanda del libro di testo

Recall that when the HGP was completed, more than 40 percent of the genes identified had unknown functions. The PANTHER database provides access to comprehensive and current functional assignments for human genes (and genes from other species).

Go to http://www.pantherdb.org/data/. In the frame on the left side of the screen locate the 'Quick links' and use the 'Whole genome function views' link to a view of a pie chart of current functional classes for human genes. Mouse over the pie chart to answer these questions. What percentage of human genes encode transcription factors? Cytoskeletal proteins? Transmembrane receptor regulatory/adaptor proteins?

811
views
Domanda del libro di testo

How do high-throughput techniques such as computer-automated, next-generation sequencing, and mass spectrometry facilitate research in genomics and proteomics? Explain.

850
views