Abstract
Protein translocation across biological membranes is one of the most important processes for living of cells. Sec-pathway mediated translocation of unfolded proteins through SecYE translocon is one of the main protein translocation processes. Bacteria and Plants possess SecA, the essential translocation factor. Recently,the relationship between SecA2, non essential translocation factor, and bacterial virulence has been demonstrated. In plants, Sec-pathway is conserved as thylakoid import pathway. However, this pathway has not been studied in detail, and Accessory Sec-pathway has not been discovered in plants.
Cyanidioschyzon merolae, primary red alga, is encoded two secA genes in nucleus and plastid genome. Both secA genes are transcribed and amino acid sequences are highly conserved with other SecAs. Functional analysis of these secA genes might obtain new knowledge of SecA functions and demonstrate Accessory Sec-pathway in plants.We have examined protein interactions between C. merolae SecAs and measured ATPase activities.
