The Translocon at the Outer envelope membrane of Chloroplasts (TOC) complex transports nuclear-encoded proteins into plastids, and a receptor of this complex, Toc132 seems to recognize chloroplast-destined precursor proteins and regulate their presentation to the translocation channel through GTP hydrolysis. In Arabidopsis thaliana, four psToc159 homologs are identified, termed atToc159(AT4G02510) , atToc132(AT2G16640) , atToc120(AT3G16620) and atToc90( AT5G20300) .
