The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)

Structural investigation of disordered stress proteins. Comparison of full-length dehydrins with isolated peptides of their conserved segments.

Dehydrins constitute a class of intrinsically disordered proteins that are expressed under conditions of water-related stress. Characteristic of the dehydrins are some highly conserved stretches of seven to 17 residues that are repetitively scattered in their sequences, the K-, S-, Y-, and Lys-rich segments. In this study, we investigate the putative role of these segments in promoting structure. The analysis is based on comparative analysis of four full-length dehydrins from Arabidopsis (Arabidopsis thaliana; Cor47, Lti29, Lti30, and Rab18) and isolated peptide mimics of the K-, Y-, and Lys-rich segments. In physiological buffer, the circular dichroism spectra of the full-length dehydrins reveal overall disordered structures with a variable content of poly-Pro helices, a type of elongated secondary structure relying on bridging water molecules. Similar disordered structures are observed for the isolated peptides of the conserved segments. Interestingly, neither the full-length dehydrins nor their conserved segments are able to adopt specific structure in response to altered temperature, one of the factors that regulate their expression in vivo. There is also no structural response to the addition of metal ions, increased protein concentration, or the protein-stabilizing salt Na(2)SO(4). Taken together, these observations indicate that the dehydrins are not in equilibrium with high-energy folded structures. The result suggests that the dehydrins are highly evolved proteins, selected to maintain high configurational flexibility and to resist unspecific collapse and aggregation. The role of the conserved segments is thus not to promote tertiary structure, but to exert their biological function more locally upon interaction with specific biological targets, for example, by acting as beads on a string for specific recognition, interaction with membranes, or intermolecular scaffolding. In this perspective, it is notable that the Lys-rich segment in Cor47 and Lti29 shows sequence similarity with the animal chaperone HSP90.[1]


WikiGenes - Universities