The GM domain of atToc159 is sufficient for Toc159-dependent protein import into chloroplasts. Full-length, GM domain, or M domain constructs of T7-tagged atTOC159 were transformed into ppi2 protoplasts together with RbcS12[MLM/AAA]E1α-tp:GFP (A) or E1α12/RbcS-tp:GFP (B), and import of these reporter proteins was examined by western-blot analysis using an anti-GFP antibody. Expression of T7:atToc159 protein was confirmed by western-blot analysis using anti-Toc159 and anti-T7 antibodies. Pre, Precursor forms; Pro, processed forms.