The TOC GTPase Receptors: Regulators of the Fidelity, Specificity and Substrate Profiles of the General Protein Import Machinery of Chloroplasts.

摘要: More than 2500 nuclear encoded preproteins are required for the function of chloroplasts in terrestrial plants. These imported into via concerted action two multi-subunit translocons outer (TOC) and inner (TIC) membranes chloroplast envelope. This general import machinery functions to recognize proteins with high fidelity efficiency ensure that organelle biogenesis is properly coordinated developmental physiological events. Two components TOC machinery, Toc34 Toc159, act as primary receptors at surface. They interact intrinsic targeting signals (transit peptides) mediate selectivity targeting, they contribute quality control by constituting a GTP-dependent checkpoint reaction. The receptor family has expanded regulate distinct classes remodeling proteomes during plastid-type transitions accompany changes. As such, central regulators fidelity, specificity thereby contributing integration protein plastid biogenesis.