(Stockholm, Sweden)  --  A Little Falls native and 1977 University of Minnesota Duluth graduate is one of two Americans winning the 2012 Nobel Prize in chemistry today .  U-M-D alum Brian Kobilka  and Robert Lefkowitz  were honored for studies of protein receptors that let body cells sense and respond to outside signals.  The studies have been keys for developing better drugs.  The Royal Swedish Academy says Kobilka and Lefkowitz made groundbreaking discoveries on an important family of receptors known as G-protein-coupled receptors.  Fifty-seven-year-old Kobilka is a professor at the Stanford University School of Medicine.  He and Lefkowitz will share a one-point-two-million-dollar award.