UAS regulatory sequences drive expression of of an N-terminally truncated form of Hsap\CACNA1A. Wild-type Hsap\CACNA1A is a 282 kDa protein. A 75 kDa C-terminal fragment with an expanded polyglutamine tract has been implicated as a cytotoxic form of CACNA1A associated with Spinocerebellar ataxia 6 (SCA6). This construct expresses the 75 kDa protein with a normal number of glutamine repeats.