Intraflagellar transport protein 74 is essential for mouse spermatogenesis and male fertility by regulating axonemal microtubule assembly in mice

BioRxiv : the Preprint Server for Biology
Lin ShiZhibing Zhang


IFT74 is a component of the core intraflagellar transport (IFT) complex, a bidirectional movement of large particles along the axoneme microtubules for cilia formation. In this study, we investigated its role in sperm flagella formation and discovered that mice deficiency in IFT74 in male germ cells were infertile associated with low sperm counts and immotile sperm. The few developed spermatozoa displayed misshaped heads and short tails. Transmission electron microscopy revealed abnormal flagellar axoneme in the seminiferous tubules where sperm are made. Clusters of unassembled microtubules were present in the spermatids. Testicular expression levels of IFT27, IFT57, IFT81, IFT88 and IFT140 were significantly reduced in the mutant mice, with the exception of IFT20 and IFT25. The levels of ODF2 and SPAG16L proteins were also not changed. However, the processed AKAP4 protein, a major component of the fibrous sheath, a unique structure of sperm tail, was significantly reduced. Our study demonstrates that IFT74 is essential for mouse sperm formation, probably through assembly of the core axoneme and fibrous sheath, and highlights a potential genetic factor (IFT74) that contributes to human infertility in men.

Related Concepts

Germ Cells
Male Population Group
Laboratory mice
Mice, Mutant Strains
Microtubule Proteins

Related Feeds

BioRxiv & MedRxiv Preprints

BioRxiv and MedRxiv are the preprint servers for biology and health sciences respectively, operated by Cold Spring Harbor Laboratory. Here are the latest preprint articles (which are not peer-reviewed) from BioRxiv and MedRxiv.