Human Tidl is a human homolog of bacterial DnaJ and the Drosophila tumor suppressor Tid56 that have two alternatively spliced isoforms Tid-Long and Tid-Short (Tidl-L and Tidl-S),which differ only at their carboxyl-termini.In flies the absence of Tid56 results in abnormal differentiation and morphogenesis, giving rise to Tumorous imaginal discs that lead to embryonic lethality.In Tid56 mutants the imaginal discs fail to develop into their respective adult structures and instead proliferate to form lethal tumors that maintain their neoplastic characteristics when transplanted into wild-type flies.Tid1 is also a member of the DnaJ family of molecular co-chaperones.