HSP40 Antibody: RPE

HSP40 proteins, also known as DnaJ homologs, are evolutionarily conserved molecular co-chaperones essential for maintaining protein homeostasis. Characterized by a conserved J-domain within their N-terminal region, these proteins bind to HSP70s and stimulate their ATPase activity—an essential step for HSP70-mediated protein folding, unfolding, translocation, and degradation. By stabilizing the interaction between HSP70 and its substrate proteins, HSP40s effectively determine the functional activity of the HSP70 chaperone system. This interaction is central to the cellular response to proteotoxic stress, particularly in neurons, where the accumulation of misfolded proteins is a hallmark of neurodegenerative diseases such as Alzheimer’s, Parkinson’s, and Huntington’s disease. HSP40 (HDJ1), a 40 kDa mammalian protein, is homologous to bacterial DnaJ and yeast proteins such as YDJ1 and SIS1. It is inducible by stress and translocates from the cytoplasm to the nucleus and nucleoli, mirroring the behavior of HSP70 family members. This dynamic localization suggests a role in nuclear protein quality control and stress signaling. Through its regulation of HSP70 and participation in multi-chaperone complexes, HSP40 is a critical modulator of neuronal proteostasis. Its dysfunction or dysregulation may contribute to the pathogenesis of neurodegenerative disorders, making it a promising target for therapeutic intervention in neuroscience.

DNAJB1, DNAJ1, HDJ1, HSPF1, HSP40, DnaJ homolog subfamily B member 1, DnaJ protein homolog 1, Heat shock 40 kDa protein 1, Human DnaJ protein 1, hDj-1, DnaJ (HSP40) homolog subfamily B member 1

0.5 µg/ml of SPC-100 was sufficient for detection of HSP40 in 20 µg of heat shocked HeLa cell lysate by colorimetric immunoblot analysis using Goat anti-rabbit IgG:HRP as the secondary antibody.

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