The Des Moines-based Principal Financial Group is sponsoring a nationwide art tour featuring works from the Smithsonian. Principal spokesperson Chris Reidel-King says it’s called “Treasures To Go”.Reidel-King says as the Smithsonian’s American Art Museum undergoes renovations for the next three years, the displaced works of art will travel around the country. “Treasures To Go” will stop at the Des Moines Art Center next spring, one of 70 cities where the exhibition will stop.Reidel-King says The Principal has a long-standing committment to art, with a vast corporate art collection.Sculptures, murals and hanging oil paintings decorate The Principal’s offices, and Reidel-King says the art gives the workplace vitality.The Principal’s permanent art collection and the “Treasures To Go” exhibition will be featured on the C-N-B-C t-v show “The Edge” Tuesday at 6:30 p.m.