Probably required during the final stages of sperm tail maturation in the testis and/or epididymis, where extensive disulfide bonding of fibrous sheath (FS) proteins occurs. May be involved in the reduction of disulfide bonds within the sperm FS components. In vitro, it has neither NDP kinase nor reducing activity on disulfide bonds. Defects in NME8 are the cause of primary ciliary dyskinesia type 6 (CILD6). CILD is an autosomal recessive disorder characterized by axonemal abnormalities of motile cilia. Respiratory infections leading to chronic inflammation and bronchiectasis are recurrent, due to defects in the respiratory cilia; reduced fertility is often observed in male patients due to abnormalities of sperm tails. Half of the patients exhibit situs inversus, due to dysfunction of monocilia at the embryonic node and randomization of left-right body asymmetry. Primary ciliary dyskinesia associated with situs inversus is referred to as Kartagener syndrome. Note: This description may include information from UniProtKB.
Protein type: Kinase, nucleoside diphosphate; NDK family; Other group; Oxidoreductase