DnaJ heat shock protein family member B13 (DNAJB13)

DnaJ heat shock protein family member B13 (DNAJB13) is a type II Hsp40 co-chaperone protein highly expressed in testis and essential for the structure and motility of cilia and sperm flagella[2][3]. It localizes to the radial spokes of the axoneme—an internal scaffold in flagella/cilia—and plays a key role in stabilizing and assembling these structures, which are fundamental for sperm movement and ciliary beating in respiratory epithelia[2][3][1]. DNAJB13 interacts with septin 4 in the sperm annulus and is required during terminal sperm differentiation. Loss-of-function variants are directly linked to primary ciliary dyskinesia—a disorder of dysfunctional cilia leading to respiratory disease—and to male infertility, primarily via abnormal sperm motility (asthenozoospermia) and morphology[2][3][1]. There is no evidence DNAJB13 is a direct target of pharmacological agents. Rather, its clinical relevance is as a genetic cause of ciliopathies and infertility, and as a biomarker in these contexts[2][3].

Other names

DnaJ (Hsp40) homolog, subfamily B, member 13DNAJB13TSARG3TSARG6RSPH16ATestis spermatogenesis apoptosis-related gene 3 proteinTestis spermatogenesis apoptosis-related gene 6 proteinTestis spermatocyte apoptosis-related gene 6 proteinTestis and spermatogenesis cell-related protein 6radial spoke 16 homolog ACILD34DnaJ-like protein

Not applicable. No drugs or small molecules with defined mechanism of action targeting DNAJB13[3][2].