Title:Mammalian Sperm Protamine Extraction and Analysis: A Step-By-Step Detailed Protocol and Brief Review of Protamine Alterations
VOLUME: 25 ISSUE: 5
Author(s):Ada Soler-Ventura, Judit Castillo, Alberto de la Iglesia, Meritxell Jodar, Ferran Barrachina, Josep Lluis Ballesca and Rafael Oliva*
Affiliation:Molecular Biology of Reproduction and Development Research Group, Institut d`Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain, and Biochemistry and Molecular Genetics Service, Hospital Clinic, Barcelona, Molecular Biology of Reproduction and Development Research Group, Institut d`Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain, and Biochemistry and Molecular Genetics Service, Hospital Clinic, Barcelona, Molecular Biology of Reproduction and Development Research Group, Institut d`Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain, and Biochemistry and Molecular Genetics Service, Hospital Clinic, Barcelona, Molecular Biology of Reproduction and Development Research Group, Institut d`Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain, and Biochemistry and Molecular Genetics Service, Hospital Clinic, Barcelona, Molecular Biology of Reproduction and Development Research Group, Institut d`Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain, and Biochemistry and Molecular Genetics Service, Hospital Clinic, Barcelona, Clinic Institute of Gynecology, Obstetrics and Neonatology, Hospital Clinic, Barcelona, Molecular Biology of Reproduction and Development Research Group, Institut d`Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain, and Biochemistry and Molecular Genetics Service, Hospital Clinic, Barcelona
Keywords:Protamines, sperm, protein isolation, male infertility, acid-urea electrophoresis, nuclear proteins, sperm chromatin.
Abstract:Background: Protamines are the most abundant sperm nuclear proteins and pack approximately
the 92-98% of the mammalian sperm DNA. In mammals, two types of protamines
have been described, the Protamine 1 (P1) and the Protamine 2 (P2) family. The deregulation of the
relative P1/P2 ratio has been correlated to DNA damage, alterations in seminal parameters, and low
success rate of assisted reproduction techniques. Additionally, the extraction and analysis of protamines
have been important to understand the fundamental aspects of the sperm chromatin structure
and function, protamine sequence conservation among species, and sperm chromatin alterations
present in infertile males. However, protamines show a particular chemical nature due to its
special amino acid sequence, extremely rich in arginine and cysteine residues. Because of these
peculiar characteristics of protamines, their extraction and analysis is not as straightforward as the
analysis of other chromatin-associated proteins, for which many detailed protocols are already
available.
Conclusion: A step-by-step protocol was needed to facilitate protamine analysis to researchers
interested in their implementation. Therefore, in order to contribute to fulfill this need, here we
provide a detailed protocol, which should be useful to research teams and laboratories interested in
the protamine field. In addition, we also briefly review the different studies published so far on
protamine alterations and male infertility.
