Archean core promoter region information content and its relation with optimal growth temperature.

ARIEL APTEKMANN; A NADRA

San Carlos de Bariloche

Conferencia; V Congreso de la A2B2C; 2014

A2B2C

We studied the relation between optimal growth temperature (OGT) and information content (IC), in the core promoter region of all the archeal genomes published to date, by calculating the information content of the motiff that represents the TATA binding site (TBS). We have tested several different approaches to predict transcription start sites (TSS) in a given genome we then used motiff prediction software in the flanking regions to the TSS, we constructed a database, compiling already available information from published sources, that contains characteristic growth conditions for each strain. Our work hipotesis is that protein-dna interfase in thermophiles should be different from that of mesophiles, in particular we propose and test a positive correlation between information content of binding sites and OGT in archeas. We show that the information content increases with increasing optimal growth temperature, and this effect cannot be explained solely by an increased CG composition. Selective pressure towards binding sites with higher binding affinity to the protein could be the reason for this correlation. The established Rseq = Rfreq from molecular information theory doesnt take into account the effect of temperature as a selective pressure acting to skew the posible binding sites, and creating another cause for an increment in Rseq that doesnt apply to Rfreq. Since entropy effects increase with temperature, Shannon entropy effects might as well.