Static SAXS measurements of CrTIG1 in complex with peptides of the putative interaction partners ATP-Synthase (AtpB) und Ribulose bisphosphate carboxylase (RuBisCO)

Trigger factor belongs to the group of molecular chaperones that are involved in the folding and maturation of newly synthesized proteins within a cell. Trigger factor is only found in bacterial cells and in the chloroplast of eukaryotic, photosynthetic active cells. It has been shown that this chaperone binds to ribosomes, receives emerging nascent polypeptides and is a major ontributor to prevent premature misfolding and aggregation for a broad set of nascent polypeptides. So far, the function for protein maturation within the chloroplast is only poorly understood. Interestingly we find a strong light-dependent association of the plastidic TIG with membranes, which has not been observed for the bacterial isoform. Together with phenotypic analyses of TIG1 down-regulating cells our data indicate to an important function for the biogenesis of newly synthesized chloroplast proteins. Detailed structural data will help to elucidate the mechanism of this chaperone and to distinguish its function from the orthologous form of bacteria. CrTIG1 was also investigated with peptides of the putative interaction partners ATP-Synthase (AtpB) und Ribulose bisphosphate carboxylase (RuBisCO), respectively.