Expression pattern of polyketide synthase-2 during sea urchin development

Polyketide synthases (PKSs) are a large group of proteins responsible for the biosynthesis of polyketide compounds, which are mainly found in bacteria, fungi, and plants. Polyketides have a wide array of biological functions, including antibiotic, antifungal, predator defense, and light responses. In this study, we describe the developmental expression pattern of pks2, one of two pks found in the sea urchin genome. Throughout development, pks2 expression was restricted to skeletogenic cells and their precursors. Pks2 was first detected during the blastula stage. The transcript level peaked at hatched blastula, when all skeletogenic cell precursors expressed pks2. This was followed by a steady decline in expression in the skeletogenic cells on the aboral side of the embryo. By the prism stage, pks2 expression was limited to only 3-4 skeletogenic cells localized on the oral side.