REPRODUCTIONREVIEW New insights into epididymal function in relation to sperm maturation Jean-Louis Dacheux and Franc¸oise Dacheux UMR INRA-CNRS 7247, 37380 Nouzilly, France Correspondence should be addressed to J-L Dacheux; Email:
[email protected] Abstract Testicular spermatozoa acquire fertility only after 1 or 2 weeks of transit through the epididymis. At the end of this several meters long epididymal tubule, the male gamete is able to move, capacitate, migrate through the female tract, bind to the egg membrane and fuse to the oocyte to result in a viable embryo. All these sperm properties are acquired after sequential modifications occurring either at the level of the spermatozoon or in the epididymal surroundings. Over the last few decades, significant increases in the understanding of the composition of the male gamete and its surroundings have resulted from the use of new techniques such as genome sequencing, proteomics combined with high-sensitivity mass spectrometry, and gene-knockout approaches. This review reports and discusses the most relevant new results obtained in different species regarding the various cellular processes occurring at the sperm level, in particular, those related to the development of motility and egg binding during epididymal transit. Reproduction (2014) 147 R27–R42 Introduction sequentially throughout the epididymis. In view of these two parallel events, most investigations have The formation of fertile spermatozoa is the result of involved assessing the relationships between these two spectacular stages of cell differentiation that begin in events and identifying the epididymal signals able to the male gonad and finish in the female tract. The control spermatozoon fertility.