Resumen de Caracterització proteòmica i d'espermatozoides humans en pacients infèrtils i controls / Proteomic and molecular characterization of human spermatozoa in infertile patients and controls
Sara De Mateo López
The knowledge of the proteins that are present in the spermatozoa is an essential step towards the comprehension of their normal function and their potential alterations associated to infertility. Although many studies have been performed in human male infertility, many of the causes still remain unknown, partly due to the fact that the proteins and the mechanisms involved in spermiogenesis and in sperm function are not known in detail. Therefore, the proteomic study of the human spermatozoa through mass spectrometry is relevant both, towards improving our fundamental knowledge and the mechanisms involved in the normal sperm physiology, as well as towards a better understanding of the male infertility. This doctoral thesis has contributed to the identification of the human sperm proteome through two-dimensional gels and mass spectrometry. Moreover, it has identified new correlations between the abundance of certain proteins and the seminal parameters related to male infertility such as the protamine content, DNA damage and sperm motility giving rise to the identification of potential diagnostic markers. In addition, the potential correlations between the protamine content and the presence of the protamine 2 precursors in the sperm cell from patients and the assisted reproductive outcomes have also been studied. Another point studied in the present thesis has been the determination, through immunofluorescent techniques, of the presence of nucleosomes and other proteins with a potential epigenetic function present in spermatozoon fractions selected through density gradients. Moreover, a protocol for the isolation of human sperm nuclei has been implemented to further identify, through mass spectrometry, minor nuclear proteins that may be important for normal sperm functioning or the embryo development.KEYWORDS: Spermatozoon, Protamines, Proteome, Male infertility, Epigenetics
