Contributions of semen to fertilization and early embryo development: (epi)genome, proteome and metabolome
Worldwide, infertility affects 10-15% of couples at reproductive age, and 30-35% of cases are thought to exclusively be due to a male factor. While the main function of sperm cells is to transport and deliver the paternal genome to the oocyte, whether semen components have an effect on fertilization and post-fertilization events has been investigated less. The semen is composed of seminal plasma and sperm. In the case of seminal plasma, proteins and distinct types of RNAs, mostly enclosed in extracellular vesicles, play a role in the uterine environment. With regard to sperm, structural components, such as the proximal centriole; proteins, like the sperm-bone oocyte activation factor, phospholipase C zeta (PLCζ); the sperm metabolic fate; RNAs; and chromatin/DNA integrity appear to develop their function not only during fertilization but also over early embryo development. A new paradigm approaching the sperm cell with a broader perspective, including the (epi)genome, proteome, transcriptome, metabolome and interactome, appears to be required in order to better understand the causes underlying male infertility, particularly those cases that are idiopathic. In this context, and even though what is known about the sperm chromatin structure is based on models, mounting evidence supports that chromatin condensation as well as DNA integrity are related to fertilizing ability, embryogenesis and may explain some cases of miscarriage. Particularly, the regions of the sperm DNA packed with histones are suggested to contain genes related to implantation. Because histones but not protamines, which are the most abundant nucleoproteins in the sperm of eutherian mammals, bear epigenetic signatures, research targeting these genes is much warranted to understand why alterations in the integrity, condensation and protamination of sperm chromatin can have a repercussion so beyond fertilization, driving embryo implantation failure and recurrent miscarriage.
Biography:
Marc graduated with a Bachelor of Science (Biology) from Girona University, an MSc in Biotechnology, and earned a European PhD in Reproductive Biology. He also graduated with a Bachelor of Political and Social Sciences from UNED, and read additional BA (Phil) courses. Previously, Marc was a Visiting Researcher at the Institute of Zoology, Zoological Society of London; Postdoctoral Research Fellow (Juan de la Cierva) at the Department of Animal Medicine and Surgery, Autonomous University of Barcelona; and a Senior Postdoctoral Research Fellow (Marie Curie) at the Nuffield Department of Women’s and Reproductive Health, University of Oxford. He moved back to the University of Girona as a Senior Research Fellow (Ramón y Cajal), and is now an ICREA Academia Professor at the Department of Biology.
Marc’s research has approached different realms of Reproductive Biology in mammals (encompassing humans, pigs, cattle, horses, donkeys, sheep, mice, cats and dogs): sperm physiology (including sperm capacitation), interactions of sperm with epithelial cells from different reproductive tissues (epididymis and fallopian tube/oviduct), presence and growth of microbes in semen and implications for its preservation, sperm cryopreservation, cryopreservation of oocytes and embryos, genetics of infertility, oocyte activation deficiency, in vitro maturation of oocytes and fertility preservation.
Website: https://www.udg.edu/ca/directori/pagina-personal?ID=2001711&language=en-US