Cut salmon lengthwise into 6 pieces. To make each roll, spoon half of rice evenly down 1 long edge of each dough piece in a 1-inch strip to within 1/4 inch of edge. Place 3 pieces salmon evenly over rice, overlapping salmon to fit if necessary. Starting at long side topped with salmon, roll up; pinch seam to seal. Sprinkle sesame seed on ungreased cookie sheet; roll and press each log in sesame seed to coat. Place rolls, seam side down, on cookie sheet.