New protein critical for mitochondria discovered

The study -- whose first author is Tanit Guitart, a PhD student in the lab of Lluís Ribas de Pouplana, ICREA professor at the Institute for Research in Biomedicine (IRB Barcelona) -- appears in the December issue of the Journal of Biological Chemistry, which is already available online.

Result of animal evolution

The SLIMP protein derives from a seryl-tRNA synthetase, universal enzymes that are crucial for the synthesis of new proteins. However, SLIMP has lost its original function and performs a different biological role, which remains to be determined. The researchers studied its possible implication in the regulation of mitochondrial division and the interaction with nucleic acids (DNA, RNA).

SLIMP evolved by duplication of the seryl-tRNA synthetase about 540 million years ago, at the beginning of the Cambrian, before the appearance of the starfish and sea urchins family. SLIMP is not present in vertebrates, and it is possible that another protein has taken over its function.

"If this were the case, we could look for the protein equivalent in vertebrates, determine its function and focus on these organisms. Here we have work for the next ten years," says Ribas.

This study was performed in collaboration with researchers in the groups devoted to Heterogenic and Multigenic Diseases and Chromatin structure and function, both at IRB Barcelona.