thylakoid membrane photosystem I accumulation factor
Members of this family, restricted to the Cyanobacteria and chloroplasts, show homology to thioredoxins. However, the core region of family protein alignment shows either one Cys residue or zero, suggesting family members may share the thioredoxin-like fold but lack redox capability. The founding member of the family, slr1796, was shown by proteomics to localize to the thylakoid membrane, consistent with taxonomic restriction to the Cyanobacteria. Targeted mutation of slr1796 shows a role in successful translation and insertion of photosystem I proteins into the thylakoid membrane.