The signaling role of inositol hexakisphosphate kinases (IP6Ks)

The past ten years have seen a contained explosion of interest in inositol pyrophosphates. The early cloning of the IP6Ks and the more recent identification of the PP-IP5Ks have allowed the development of essential experimental tools to investigate the physiological role of inositol pyrophosphates. However, for this exciting field of research to gain momentum, simpler and more reliable research protocols need to be further developed. The ability to resolve and quantify inositol pyrophosphates using gel electrophoresis (Losito et al., 2009) has dramatically altered the way we are studying this class of molecules, opening new avenues for research. The use of this technology to resolve, detect and characterize inositol pyrophosphates extracted from cells certainly represents one desirable aim. The most crucial objective, however, is to obtain definite proof of the new mechanism of post-translational modification by identifying with biophysical methods the presence in vivo of pyrophosphorylated serines. This will hopefully precipitate the development of new ways to detect this modification, for example through the production of antibodies that specifically recognize pyrophosphorylated serines.