Role of Sec translocases in plastid biogenesis

plastid biogenesis image

Sec translocases function to translocate soluble domains across membranes or insert transmembrane domains into membranes. We discovered that all organisms with green plastids have two chloroplast Sec translocases: one in the thylakoids and one in the inner envelope. To understand the different roles they play in plastid biogenesis, we have studied the individual components and function of these systems through a combination of genetics, molecular biology, and biochemistry. Localization of the two systems in different membranes is important for establishing and maintaining membrane differentiation. We are studying the sorting of individual Sec components to gain insight into how membrane-specific targeting is achieved in these organelles.


Singhal, R. and D.E. Fernandez (2017). Sorting of SEC translocase SCY components to different membranes in chloroplasts. J. Exp. Bot (in press).

Li, Y., J.R. Martin, G.A. Aldama, D.E. Fernandez, and K. Cline (2017). Identification of putative substrates of Sec2, a chloroplast inner envelope translocase. Plant Physiol. 173: 2121-2137.

Li, Y., R. Singhal, I. Taylor, P. McMinn, X. Chua, K. Cline, and D.E. Fernandez (2015). The Sec2 translocase of the chloroplast inner envelope contains a unique and dedicated SECE2 component. Plant Journal 84: 647-658.

Skalitzky, C.A., J.R. Martin, J.H. Harwood, J.J. Beirne, B.J. Adamczyk, G.R. Heck, K. Cline, and D.E. Fernandez (2011). Plastids contain a second Sec translocase system with essential functions. Plant Physiol. 155: 354-369.