Mitochondria & Golgi bodies

THE ORIGIN OF MITOCONDRIAL PROTEINS:

A typical eukaryotic cell contains roughly 10`000 different proteins, of which about 10% are in the mitochondria. Because mitochondria synthesize only a dozen proteins, they must import 99% of their proteins from the cytoplasm. In the transfer of such proteins to the mitochondria the proteins need to be located in of four positions:

In the inter membrane space, on the outside of the inner membrane, on the matrix side of the inner membrane and in the matrix.

Most proteins imported into the mitochondria are synthesized with a cleavable N-terminal targeting sequence.

THE ROLE OF GOLGI APPARATUS:

The role of Golgi apparatus is highly specialized for a variety of functions including protein glycosylation and subsequent transport of glycoproteins to their final destinations. Three compartments have been identified in the Golgi apparatus; these are termed cis, medial and Trans. Each compartment is involved in a different stage of protein processing. The last station is named the trans-Golgi network (TGN), which plays a pivotal role in directing proteins to their appropriate cellular destination.