Volume 10 Issue 12, December 2003

The protein Tom40 is the main component of the outer membrane translocation machinery for mitochondrial preproteins. A new study extends the understanding of the molecular function of Tom40, suggesting that the pore-forming protein may interact with unfolded preprotein segments to protect against aggregation.

In response to DNA double-strand breaks, histone H1.2 translocates from the nucleus into the cytoplasm, leading to the mitochondrial release of cytochrome c and subsequent apoptosis of the cell. The molecular underpinnings for these processes remain enigmatic.

Although zinc fingers are best known to interact with DNA, they can, as in the case of the TFIIIA protein, also interact with RNA. A recent crystal structure reveals that zinc fingers can take advantage of the variability of RNA structure to recognize a particular RNA fragment.