1. Stir together first 6 ingredients.
2. Remove giblets and neck from turkey; pat turkey dry. Sprinkle 1 Tbsp. brine into cavity; rub into cavity. Reserve 1 Tbsp. brine, and sprinkle outside of turkey with remaining brine; rub into skin. Chill turkey 10 to 24 hours.
3. Preheat oven to 350°. Stir together butter and reserved 1 Tbsp. brine. Loosen skin from turkey breast without totally detaching skin; spread butter mixture under skin. Replace skin, securing with wooden picks.
4. Tie ends of legs together with string; tuck wing tips under. Place turkey, breast side up, on a lightly greased (with cooking spray) rack in a large roasting pan.
5. Bake at 350° for 2 hours and 30 minutes or until a meat thermometer inserted in thickest portion of turkey thigh registers 165°. Remove from oven; let stand 30 minutes before carving.