In the recording or reproduction apparatus using a disc cassette having a shutter releasably locked in the closed position, a mechanism for opening and closing the shutter as the disc cassette is inserted into, and pulled out of, the apparatus has its closing member made by bending an elastic line wire to such a form that the locking means can pass under it without being operated to release the shutter, but its engagement with the shutter is maintained against the load however large, when the shutter is closed.