Recombinant Human Chromodomain

Chromodomain Helicase DNA binding protein 4, Mi-2b, Mi2-BETA, CHD-4, ATP-dependent helicase CHD4, Mi-2 autoantigen 218 kDa protein, EC 3.6.4.12, EC 3.6.1.

CHD4 is a member of a family of alleged chromodomain helicase-DNA-binding proteins. Biochemically, CHD4 is a component of the nucleosome transformation and deacetylase (NuRD) complex that takes part in transcription regulation. Autoantibodies targeting the CHD4 are a serologic feature of idiopathic inflammatory myopathies (IIM). In IIM Mi-2 antibodies are characterized by diagnostic sensitivity and specificity of approximately 4-18% and 98-100%, respectively. Moreover, anti-CHD4 antibodies are related to dermatomyositis (frequency up to 31%) and have a great positive predictive value for this type of disease subset. Anti-CHD4 are the only defined myositis-specific autoantibodies clearly focused to a nuclear target. An additional slightly outstanding feature of Mi-2 antibodies relates to their frequency in children, which is similar to that in adults.

CHD4 is a full-length cDNA coding for the human Mi-2 beta isoform having a molecular mass of 221,298 Dalton (pH 5.8). CHD4 protein is fused to a hexa-histidine purification tag.

Sf9 insect cells.

CHD4 is supplied in 20mM HEPES buffer pH-8.0 and 500mM NaCl.

Store at 4°C if entire vial will be used within 2-4 weeks. Store, frozen at -20°C for longer periods of time.
Avoid multiple freeze-thaw cycles.

Greater than 95% as determined by SDS-PAGE.

1. Binds IgG-type human auto-antibodies.

2. Standard ELISA test (checkerboard analysis of positive/negative sera panels); immunodot test with positive/negative sera panels.

Western blot with myositis sera ormonoclonal anti-hexa-His-tag antibody.

0.3-0.7 µg/ml (depending on the type of ELISA plate and coating buffer). Suitable for biotinylation and iodination.

SDS

Prospec's products are furnished for LABORATORY RESEARCH USE ONLY. The product may not be used as drugs, agricultural or pesticidal products, food additives or household chemicals.