Alternative splicing of exon 3b gives rise to ODF2 and Cenexin

ODF2 was first identified as the major component of the sperm tail outer dense fibers. Additionally, ODF2 is a critical component of the mature centriole of the animal centrosome where it locates to the distal appendages. Moreover, generation of primary cilia strictly depends on ODF2. The mature centriole is characterized further by recruitment of Cenexin. Albeit highly similar in sequence the relationship between ODF2 and Cenexin has not been investigated. We demonstrate here that ODF2 and Cenexin are alternative splice products by identifying a novel exon 3b encoding Cenexin specific amino acids. Even though ODF2 is the main isoform in testicular tissue RT-PCR analyses revealed that isoforms are not restricted to specific tissues.