week_2: score for the microRNA gene family orchestra
The rationale behind the following approach to score creation is based on occurrences of di-nucleatide pairs within strings of DNA sequence for microRNA genes in plants. The overall idea is to create a computer algorithm that plays a synthetic note each time it finds the CG dinucleotide within a string of DNA that is 80 nucleotides long. Each microRNA DNA sequence will be considered an instrument and the total number of microRNAs will depend on the size of the gene family in question. For instance miR156 gene family in the plant Arabidopsis thaliana is composed of 10 genes (and thus 10 different instruments in this work) whereas the miR172 gene family is composed of 5 genes (and thus 5 instruments), giving a total orchestra size of 15 different instruments to be played throughout the envisioned piece. miR172 and miR156 are involved in the regulation of flowering in Arabidopsis as well as in many other plants, their expression pattern throughout development is antagonistic and by selectively 'playing' them in the emulated order as they would in throughout plant development, a biologically inspired computer music composition could be achieved.
The general approach for the score and its realization is depicted in Figure 1. Each 80 nucleotide gene segment (for each individual microRNA gene) will be divided in 8 segments of 10 nucleotides each, with segments corresponding to musical notes DO, RE, MI, FA, SOL, LA, SI, OCT respectively. For instance, when CG di-nucleotides occur within the first segment (within the first 10 nucleotides) of the gene, the algorithm plays the musical note DO; when it occurs within the second segment (between the 10nth and 20th nucleotide) it plays the musical note RE and so on.
The resulting score for each instrument will be played and recorded in an individual audio track. This means that there will be 15 different audio track, each one for each gene instrument. The user will then play each audio track to direct and compose with the orchestra by interacting with graphical user interfaces represented by checking boxes in the browser.
Figure 1. Diagram depicting overal idea for score creation and sound composition realization via a graphical user interface in the browser.