Involved in protein precursor import into chloroplasts. Forms a voltage-dependent cation-selective channel at the inner envelope of chloroplasts, which specifically responds to a transit peptide. Associates with both the precursor and mature forms of the preprotein. Part of the Tic complex. Interacts with HSP70, HSP93 and TIC40. Interacts with the Toc complex components TOC33, TOC75 and TOC159. Interacts with LTD. Expressed in seedlings, flowers, leaves, stems and roots. Expressed throughout development. An internal domain (143-652) is sufficient for assembly into supercomplex with Toc complex. Residues 235-420 contain a binding site for preprotein transit peptides. Embryo lethal. The region 143-1016 is indicated to be located in the stroma (PubMed:12874276, PubMed:9632730) while the homologous region in pea TIC110 contains probably 4 trans-membrane domains resulting in 2 regions in the intermembrane space localized to form supercomplexes with the TOC machinery and to receive the transit peptide of preproteins. Inserts into the inner envelope membrane from the stroma after import from the cytoplasm. Belongs to the chloroplast envelope anion channel-forming Tic110 (TC 1.A.18) family.