Exons 3, 4 and 5 that encode the coiled-coiled domain of the gene product were replaced with a neomycin resistance cassette. Immunoblotting of homozygote embryonic fibroblast lysate indicated two truncated proteins were produced. Ectopic expression of similar truncated proteins in wild-type embryonic fibroblasts indicated that the truncated proteins do not interfere in a dominant negative manner with autophagy processes.