Coiled-coil domain-containing protein 181 (CCDC181) is a protein that in human is encoded by C1orf114, which is located at the Chromosome 1 at 1q24.2. The accession is Q5T1D7. Researches have recently revealed that CCDC 181 is a microtubule-binding protein that interacts with murine Hook1 in haploid male germ cells and localizes to the sperm tail and motile cilia. The disruption of Hook1 may lead to inappropriate function of spermatogenesis. The dysfunction may be related to the abnormal head shape of sperm or distinctive structural changes in flagella in sperm, which can result in male infertility. An increased rate of my gene has found in the haploid phase of male cell during meiosis, thus it is believed to relate to sperm cell and aid in spermatogenesis.