Human cardiac ryanodine receptor: preparation, crystallization and preliminary X-ray ANALysis of the N-terminal region.

Human ryanodine receptor 2 (hRyR2) is a calcium ion channel present in the membrane of the sarcoplasmic reticulum of cardiac myocytes that mediates release of calcium ions from the sarcoplasmic reticulum stores during excitation- contraction coupling. Disease-causing mutations of hRyR2 are clustered into N-terminal (amino acids 1-600), central (amino acids 2100-2500) and C-terminal (amino acids 3900-5000) regions. These regions are believed to be involved in regulation of channel gating.

Preparation, crystallization and preliminary X-ray analysis of the Fab fragment of monoclonal antibody MN423, revealing the structural aspects of Alzheimer's paired helical filaments.

Monoclonal antibody (mAb) MN423 recognizes Alzheimer's disease specific conformation of tau protein assembled into paired helical filaments (PHF). Since the three-dimensional structure of PHF is currently unavailable, the structure of MN423 binding site could provide important information about PHF conformation with the consequences for the Alzheimer's disease prevention and cure. Fab fragment of MN423 was prepared and purified.

Actin-binding domain of mouse plectin. Crystal structure and binding to vimentin.

Plectin, a large and widely expressed cytolinker protein, is composed of several subdomains that harbor binding sites for a variety of different interaction partners. A canonical actin-binding domain (ABD) comprising two calponin homology domains (CH1 and CH2) is located in proximity to its amino terminus. However, the ABD of plectin is unique among actin-binding proteins as it is expressed in the form of distinct, plectin isoform-specific versions.

Purification, crystallization and preliminary X-ray analysis of the plectin actin-binding domain.

Plectin is an abundantly expressed cytoskeletal crosslinking protein of enormous size (>500 kDa) and multiple functions. It represents one of the many members of a large family of actin-binding proteins. The actin-binding domain of mouse plectin was expressed in Escherichia coli and purified to homogeneity.