What are DNA Sequence Motifs? Why are They Important? Essay

609 Words 3 Pages
What are DNA sequence motifs? Why are they important? DNA sequence motifs are used to profile a genomic region in DNA. They are characterized as short nucleotide patterns and are conserved at biologically related genomes. The complexity of these patterns ranges from a simple and short subsequence (5-20 bp long) to palindromic and space dyed subsequences. In essence, motifs are considered as a means of enciphering DNA and are key element for defining regulatory networks and further understand the interactions between transcription factors and DNA [].

How are motifs formulated?
There are several models that could be used to represent a sequence motif, including but not limited to consensus sequences and position weight matrices (PWMs).
…show more content…
What are DNA sequence motifs? Why are they important? DNA sequence motifs are used to profile a genomic region in DNA. They are characterized as short nucleotide patterns and are conserved at biologically related genomes. The complexity of these patterns ranges from a simple and short subsequence (5-20 bp long) to palindromic and space dyed subsequences. In essence, motifs are considered as a means of enciphering DNA and are key element for defining regulatory networks and further understand the interactions between transcription factors and DNA [].

How are motifs formulated?
There are several models that could be used to represent a sequence motif, including but not limited to consensus sequences and position weight matrices (PWMs). Consensus sequences depict the type of nucleotides that exist at each position using symbolic codes. These codes reflect the certainty of the type of nucleotide that occurs at a particular position. For example, the code [A] refers to Adenine, whereas [Y] stands for Cytosine or Thymine (http://www.bioinformatics.org/sms/iupac.html). Consensus sequences are compact and suit enumerative based analysis, where a binary decision is sufficient (either a match or a mismatch). However, in some cases it is desirable to measure how well a genomic site matches a motif (it indicates the binding affinity). To this end, PWMs encompass broad and probabilistic measures of nucleotides occurrence in motifs. This model is a matrix consisting of nucleotides
Open Document