Component of the nexin-dynein regulatory complex (N-DRC), a key regulator of ciliary/flagellar motility which maintains the alignment and integrity of the distal axoneme and regulates microtubule sliding in motile axonemes (By similarity). Plays a critical role in the assembly of N-DRC and also stabilizes the assembly of multiple inner dynein arms and radial spokes. Coassembles with DRC1 to form a central scaffold needed for assembly of the N-DRC and its attachment to the outer doublet microtubules (PubMed:24094744). Component of the nexin-dynein regulatory complex (N-DRC). Highly expressed in adult testis, in spermatocytes and spermatids. Also observed in spermatogonia. Not detected in Leydig cells, nor in fetal testis (at protein level). The disease is caused by variants affecting the gene represented in this entry. Cilia ultrastructure show normal outer dynein arms, radial spokes and central pairs, but a reduction in inner dynein arms and nexin links. In 5%-15% of cilia, microtubules are disorganized. Nasal epithelial cilia reveal a stiff, dyskinetic cilia waveform. Belongs to the DRC2 family. Truncated N-terminus.