Protein Modification part 3 of 3

Ubiquitin in pro‑inflammatory signalling - chains of command
by:Karine Enesa and Paul C. Evans

The 2004 Nobel Prize in Chemistry was awarded to Aaron Chiechanover, Avram Hershko and Irwin Rose for their pioneering studies of ubiquitination and its role in regulating protein stability. Now, 30 years after their discovery, we are beginning to understand the pleiotropic nature of ubiquitin and its roles in diverse physiological processes. Here we review an emerging concept that the signalling pathways that control inflammation are tightly regulated by a multitude of ubiquitination and deubiquitination reactions.


Palmitoylation - putting on fat Marie-
by:José Bijlmakers

The modification of proteins by the attachment of palmitate is a reversible process that has profound effects on protein function. Although palmitoylation was first documented almost 30 years ago, it is still poorly understood. Progress in this field has been hampered by the elusive nature of the enzymes involved and the absence of an obvious consensus palmitoylation motif. However, major steps forward have recently been made. The cloning of two yeast enzymes revealed the existence of a family of palmitoyltransferases, and new techniques have been developed for the large-scale detection and identification of the palmitoyl-proteome.


Macromolecular crystallography - new light on protein structure
by: Armin Wagner

X‑ray diffraction is the method of choice to determine structural information from biological macromolecules to atomic resolution. This technique depends on the availability of single crystals of protein, which are notoriously difficult to produce. It can take months or even years to find crystallization conditions capable of producing crystals with sufficient diffraction quality. During the last few years the field of MX (macromolecular crystallography) has undergone considerable change and most of the steps from protein expression to structure solution have been automated, speeding up the process significantly. Facilities such as Diamond Light Source, the new UK synchrotron radiation source in Oxfordshire, have been developed to incorporate new automation technologies and Diamond will provide an important user resource for XRD (X‑ray diffraction) experiments on crystals of biological macromolecules. Furthermore, in collaboration with Professor So Iwata (Imperial College and Diamond Light Source) and funded by the Wellcome Trust, Diamond Light Source is developing a laboratory dedicated specifically to solving the structure of membrane proteins, the crystallization of which poses a particular problem to the crystallographer.