ARMC9 Antibody

Definition and Biochemical Characteristics

The ARMC9 antibody targets the armadillo repeat-containing protein 9 (ARMC9), a 92-kDa protein (UniProt ID: Q7Z3E5) with two isoforms (76 kDa and 92 kDa). Its structure includes armadillo repeats, coiled-coil domains, and a LisH motif critical for ciliary function . The antibody is typically raised against recombinant ARMC9 fusion proteins (e.g., Ag27511) and purified via Protein A chromatography .

Applications in Research

The ARMC9 antibody is validated for:

• Western blot (WB): Detects ARMC9 in lysates of human fibroblasts, SH-SY5Y cells, and rodent tissues .

• Immunohistochemistry (IHC): Localizes ARMC9 to ciliary basal bodies and centrioles in tissue sections .

• Co-immunoprecipitation (Co-IP): Confirms interactions with ciliary proteins like TOGARAM1 and CSPP1 .

Recommended Dilutions:

• WB: 1:5000–1:50000 (Proteintech) .

• IHC: 1:200–1:500 (Atlas Antibodies) .

a. Role in Joubert Syndrome

Mutations in ARMC9 cause JBTS, a recessive neurodevelopmental disorder. The antibody has been used to:

• Validate ARMC9 knockdown in zebrafish models, inducing ciliopathy phenotypes (e.g., curved body shape, retinal dystrophy) .

• Demonstrate ARMC9 localization to the basal body and proximal cilium in human RPE1 cells .

b. Protein Interactions

The antibody facilitated the discovery of ARMC9’s interaction network, including:

• TOGARAM1: Co-localization assays confirmed direct binding, with TOGARAM1 mediating microtubule binding .

• CSPP1/CEP104: Co-IP experiments revealed complexes critical for ciliary microtubule assembly .

c. Validation Studies

• siRNA Knockdown: ARMC9 antibody detected a 70% reduction in protein levels after ARMC9 siRNA treatment in RPE1 cells .

• PalmMyr-CFP Assay: Confirmed ARMC9-TOGARAM1 interaction via fluorescence colocalization .