PROTEOMICS OF THE SPERMATOZOON

The study of the sperm proteins is crucial for un-derstanding its normal function and alterations in infertile patients. The sperm is a highly special-ized cell with a very large flagella, with little cy-toplasm and a highly condensed nucleus. The most abundant proteins in the nucleus of mammalian sperm are the protamines. The main functions of the protamines are the condensation of the DNA, possibly contributing to the generation of a more hydrodynamic sperm head and to the protection of the genetic message. However, in addition to prot-amines, about 5.0-15.0 % of the paternal genome is also complexed with histones and histone vari-ants. It has also demonstrated a differential distri-bution of genes in regions associated with histone and protamine-associated regions, suggesting a po-tential epigenetic relevance in embryonic develop-ment. More recently, detailed lists of proteins have been described corresponding to the different com-partments of the sperm cell thanks to the applica-tion of recent proteomic techniques based on mass spectrometry (MS). Differential proteomics is also being applied to identify the presence of protein ab-normalities found in infertile patients