Phylogenetic analyses with proximal promoter from skeletal and cardiac calsequestrins

Calsequestrin (CASQ) is the main calcium binding protein of the sarcoplasmic reticulum. In mammalian muscles, it exists as a skeletal isoform (CASQ1) found in fast- and slow-twitch skeletal muscles and a cardiac isoform (CASQ2) expressed in the heart and slow-twitch muscles. Evolutionary biology studies have a great impact to problems in medicine because evolutionary thinking do not displace other approaches to medical science, such as molecular medicine and cell and developmental biology, but that evolutionary insights can combine with and complement established approaches. Thus, we followed evolutionary biology approach by studing Casq promoters evolution. Phylogenetic analyses were performed using the minimum promoter of CASQ1 and CASQ2. Emerged topological discordances from the comparison between CASQ promoter based phylogenetic tree and amino acid based phylogenetic tree showed similar, but not identical evolutionary pathways.