The 12th International Symposium on Spermatology

spermatozoa. Because spermatozoa are largely incapable of de novo gene transcription and contemporaneous protein translation, their biology is highly dependent on changes in their proteomic landscape mediated by myriad posttranslational modifications, including the acquisition or loss of entire proteins. Proteomic changes in the epididymis, for example, are central to our understanding of how spermatozoa metamorphose from the dysfunctional entities that exit the testes into one of the most sophisticated functionally-differentiated cells in biology. Proteomic changes are also central to our understanding of capacitation, the mysterious process by which spermatozoa regulate their maturation in the female tract so that they are finally ready to initiate their search for an oocyte and, having attained that goal, of then engaging in the complex cascade of cellular interactions that result in fertilization. Age-old questions around the capacity of spermatozoa to suddenly recognize the egg following capacitation are yielding to a range of technologies including advanced proteomics, proximity ligation assays and flow cytometry to generate vital information on the activation and surface expression of molecules involved in sperm–zona interaction. The recent availability of instruments capable of the detailed resolution of proteomic profiles is also having a direct impact on our ability to understand the intricacies of chromatin remodelling during the final stages of spermiogenesis. These studies are helping us to resolve the very complex arrangement of protamines and histones in sperm chromatin that may ultimately influence patterns of gene expression in the early embryo. Of particular interest are reports that the proteins intimately associated with sperm DNA may themselves present a complex array of posttranslational modifications, including methylations and acetylations, which may constitute vital epigenetic information of T he 12 th International Symposium of Spermatology continued the excellent tradition of this meeting since its inception in 1969 when the first Symposium was held in Italy under the Chairmanship of Professor Baccio Baccetti. This unique Symposium is held every 4 years and serves as a beacon for sperm cell biologists from all over the world, regardless of which species, animal or plant, they are working on. This willingness to embrace the fundamental biology of this distinctive cell type without species limitations is one of the hallmarks of this Symposium. For sperm biologists ‑ it is our Olympics. The meeting in Newcastle, NSW brought together around 300 biologists from more than 22 different countries covering North and South America, Africa, Europe, Asia and Australia. Given the considerable …