ARP5 Antibody

DNA Repair and Chromatin Remodeling

• Role in INO80 Complex: ARP5 is essential for recruiting the INO80 complex to DNA double-strand breaks (DSBs) in yeast, mammals, and plants. Mutant Arabidopsis ARP5 plants exhibited hypersensitivity to DNA-damaging agents (e.g., bleocin), confirming its conserved role in DSB repair .

• Epigenetic Regulation: ARP5-deficient plants showed developmental defects, including dwarfism and delayed stomatal development, linking chromatin remodeling to multicellular growth .

Muscle Differentiation and Disease

• Inhibition of Myogenic Factors:

  • ARP5 binds to the cysteine-rich (CR) region of MyoD and MyoG, blocking their ability to activate muscle-specific genes. In rhabdomyosarcoma (RMS) cells, ARP5 depletion restored myogenic differentiation, reducing tumorigenicity .

  • In vivo studies showed that ARP5 overexpression in mouse muscle led to atrophy and reduced expression of myosin heavy chain (Myh4) and troponin (Tnni1) .

Mechanistic Insights from Functional Studies

• MyoD/MyoG Inhibition: ARP5 disrupts MyoD’s interaction with Pbx1-Meis1 heterodimers at enhancer regions, reducing Brg1 (a chromatin remodeler) recruitment and H3K27 acetylation at muscle gene loci .

• INO80-Independent Roles: While ARP5 is a core INO80 subunit, its antimyogenic function in RMS operates independently of the complex .

Technical Advancements

• Antibody Validation: ARP5 monoclonal antibodies (e.g., MAbARP5a/b) were generated using recombinant Arabidopsis ARP5 with a C-terminal His-tag, enabling precise localization in plant and mammalian nuclei .

• Protocols: Standardized WB, IF, and IP protocols for ARP5 are available, facilitating reproducibility in detecting its 68 kDa band across species .