Native - Calf Thymus
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Polymyositosis (PM) and dermatomyositis (DM) are idiopathic inflammatory myopathies. The existence of autoantibodies to nuclear and cytoplasmic antigens, in particular to the aminoacyl-tRNA synthetase group of enzymes, in the sera of up to 89% of patients indicates that these diseases have an autoimmune origin. The most common autoantibody in PM and DM is anti Jo-1, occurring in 15-20% of all myositis patients and about 30% of adult PM patients.
Jo-1 autoantibodies are capable of inhibiting the activity of the target antigen (HRS) and can immunoprecipitate labelled enzyme as well as its specific tRNA. HRS has a molecular weight of 55 kDa in SDS-polyacrylamide electrophoresis, and is believed to exist as a dimer in its native state. The amino acid sequence of human Jo-1 antigen has been determined by cloning and sequencing its cDNA. It contains three structural motifs typical of class IIa aminoacyl transferases and two signature regions common to histidyl-tRNA synthetases. The human enzyme amino acid sequence shows significant homology to those of the enzymes from yeast (47.5%) and E. coli. It is predicted to have a coiled-coil α-helical structure that is characteristic of many autoantigens and which contains the major autoantigenic epitope. Polymyositis Dermatomyositis Please log in to view certificates of analysis for this item
Polymyositosis (PM) and dermatomyositis (DM) are idiopathic inflammatory myopathies. The existence of autoantibodies to nuclear and cytoplasmic antigens, in particular to the aminoacyl-tRNA synthetase group of enzymes, in the sera of up to 89% of patients indicates that these diseases have an autoimmune origin. The most common autoantibody in PM and DM is anti Jo-1, occurring in 15-20% of all myositis patients and about 30% of adult PM patients.
Jo-1 autoantibodies are capable of inhibiting the activity of the target antigen (HRS) and can immunoprecipitate labelled enzyme as well as its specific tRNA. HRS has a molecular weight of 55 kDa in SDS-polyacrylamide electrophoresis, and is believed to exist as a dimer in its native state. The amino acid sequence of human Jo-1 antigen has been determined by cloning and sequencing its cDNA. It contains three structural motifs typical of class IIa aminoacyl transferases and two signature regions common to histidyl-tRNA synthetases. The human enzyme amino acid sequence shows significant homology to those of the enzymes from yeast (47.5%) and E. coli. It is predicted to have a coiled-coil α-helical structure that is characteristic of many autoantigens and which contains the major autoantigenic epitope. 0
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HisRS
Histidine tRNA ligase