Novel repair system discovered in algae may yield new tools for biotechnology

A new way of fixing inactive proteins has been discovered in an algae, which uses chloroplast extracts and light to release an interrupting sequence from a protein. 

Research specialist Stephen Campbell and Professor David Stern at the Boyce Thompson Institute report the discovery in the July 29 issue of the Journal of Biological Chemistry. This repair system may have applications in agriculture and biotechnology because it could potentially be harnessed to enable proteins to become active only in the light.

Many proteins contain extra sequences, called insertions, that can disrupt their function. The current paper demonstrates that the algae Chlamydomonas reinhardtii has the necessary toolkit to repair proteins by removing these insertions.

Campbell discovered this new repair system while purifying a protein from the chloroplasts of C. reinhardtii that can cut RNA. Upon sequencing the protein, he identified it as RB47, a protein that was not known to have any RNA-cleaving ability. Campbell noticed that the middle of the protein was missing. When he compared the protein sequence to its corresponding gene sequence, the protein was much shorter than expected.

In future work, the researchers plan to investigate exactly how the insertion becomes spliced out of the protein and which plant factors facilitate its removal. They also aim to understand the purpose of the insertion, and whether the algae can control the splicing to respond to changes in the environment.

This new type of repair system provides intriguing possibilities for biotech applications.