Analysis Note

ControlLiver, heart or skeletal muscle.

Application

Immunofluorescence:
1:100-1:1,000. Fixation of cells in ice cold acetone or 4% paraformaldehyde is recommended. Due to the subcellular localization of frataxin in the mitochondria, cells should be permeabilized in the presence of detergent prior to incubation with primary antibody.

ELISA:
A previous lot of this antibody was used on ELISA.

Western blot (natural and recombinant protein):
1:5,000; mitochondrial preparations are recommended for consist signals (see Santos, 2001).

Optimal working dilutions must be determined by the end user.

Detect Frataxin using this Anti-Frataxin Antibody, exon 4, clone 1G2 validated for use in ELISA, IC, IF & WB.

General description

Frataxin is a monomeric mitochondrial protein that is believed to be involved in iron homeostasis through an unknown mechanism. Expression of frataxin is highest in tissue rich with mitochondria including liver, heart, and skeletal muscle (Campuzano, 1996; Koutnikova, 1997). Frataxin is expressed as a 30 kDa precursor (transient; 210 amino acids) that is processed within in the mitochondria in two steps catalysed by the mitochondrial processing peptidase (MPP) to yield the mature protein (Koutnikova, 1998). The first step involves cleavage of the first 41 N-terminal amino acids by MPP yielding a transient intermediate of approximately 20 kDa (aa 42-210). Further cleavage of the N-terminus of this 20 kDa intermediate by MPP results in the mature 18 kDa frataxin protein (aa 56-210). Defects in the gene encoding frataxin are implicated as the cause of Friedreich′s ataxia, an autosomal recessive, progressive degenerative disease characterized by neurodegeneration and cardiomyopathy. In the majority of cases of Friedreich′s ataxia, there is an expansion of a trinucleotide repeat in the first intron of the gene encoding frataxin resulting in a marked decrease in frataxin expression, perhaps due to the formation of some unusual yet stable DNA structure that interferes with transcription (Campuzano, 1997; Bidichandani, 1998). This reduction in frataxin expression results in the accumulation of unchelated iron in the mitochondria, inhibition of mitochondrial iron-sulfer proteins, and iron mediated oxidative stress (Foury, 1997; for review see Puccio, 2000).

Immunogen

Epitope: exon 4

Full length human Frataxin fused to TrpE.

Legal Information

CHEMICON is a registered trademark of Merck KGaA, Darmstadt, Germany

Other Notes

Concentration: Please refer to the Certificate of Analysis for the lot-specific concentration.

Physical form

Mouse monoclonal ascites IgG1κ in buffer containing liquid with no preservatives.

Quality

Routinely evaluated by Western Blot on PC12 lysates.

Western Blot Analysis:
1:1000 dilution of this lot detected Frataxin on 10 µg of PC12 lysates.

Specificity

Expected to cross-react with human.

Human Frataxin. MAB1594 recognizes only isoforms of frataxin containing exon 4. On Western blots of normal human muscle, heart, cerebellum, and spinal cord extracts, MAB1594 recognizes a band migrating at approximately 18 kDa corresponding to processed frataxin (Campuzano, 1997). Slight cross reactivity with myosin may be observed by Western blot. Immunofluorescent labeling of HeLa cells with MAB1594 demonstrates that frataxin is predominantly localized in the mitochondria (Campuzano, 1997).

Storage and Stability

Stable for 1 years at -20°C in undiluted aliquots from date of receipt.
Handling Recommendations: Upon first thaw, and prior to removing the cap, centrifuge the vial and gently mix the solution. Aliquot into microcentrifuge tubes and store at -20°C. Avoid repeated freeze/thaw cycles, which may damage IgG and affect product performance

Target description

~ 18 kDa