The 5' end and promoter region of the alpha-subunit gene of chicken muscle acetylcholine receptor was mapped and sequenced. It includes a TATA and a CAAT box and a potential Sp1-binding site. When inserted in front of the chloramphenicol acetyltransferase gene, this promoter (including 850 base pairs of upstream sequence) directed high transient chloramphenicol acetyltransferase expression in transfected mouse C2.7 myotubes but not in C2.7 myoblasts or nonmyogenic 3T6 cells.