header header
Molecular Biology of Reproduction and Development




Contribution of human sperm proteins to the development and epigenome of the preimplantation embryo 2019-03-13
In this work we compiled 6871 proteins identified and reported in sperm, 1376 in the oocyte and 1300 in blastocyst. Data mining revealed that 103 sperm proteins with known roles in the processes of fertilization and 93 with roles in early embryo development. Additionally, 560 sperm proteins have been found to be involved in modulating gene expression by regulation of transcription, DNA methylation, histone post-translational modifications and non-coding RNA biogenesis. Some of these proteins may be critical for gene expression regulation after embryo genome activation, and therefore, may be potentially involved in epigenetic transmission of altered phenotypes. Furthermore, the integrative analysis of the sperm, oocyte and blastocyst proteomes and transcriptomes revealed a set of embryo proteins with an exclusive paternal origin, some of which are crucial for correct embryogenesis and, possibly, for modulation of the offspring phenotype. Hum Reprod Update. 2018 Sep 1;24(5):535-555. doi: 10.1093/humupd/dmy017
Semen proteomics and male infertility 2018-02-26
High-throughput technologies have revealed that, contrary to the idea that sperm cells are simply a silent delivery vehicle of the male genome to the oocyte, the sperm cells in fact provide both a specific epigenetically marked DNA together with a complex population of proteins and RNAs crucial for embryogenesis. Similarly, -omic technologies have also enlightened that seminal fluid seems to play a much greater role than simply being a medium to carry the spermatozoa through the female reproductive tract. This publication is a review that updates the numerous proteomics studies performed on semen, including spermatozoa and seminal fluid. In addition, an integrative analysis of the testes, sperm and seminal fluid proteomes is also included providing insights into the molecular mechanisms that regulate the generation, maturation and transit of spermatozoa (Jodar et al., J Proteomics. 2017;162:125-134).
Small RNA characterization in human sperm cells 2015-08-01
In order to better understand the function and origin of sperm small RNAs we sequenced and characterized the small RNA content of sperm samples. Interestingly 182 microRNAs were detected predicting targets among sperm-specific genes. The most abundant class of small noncoding RNAs in sperm are PIWI-interacting RNAs (piRNAs). We also found that several human protein-coding genes contain antisense predicted targets of pseudogene-derived piRNAs in the male germline and these piRNAs are still found in mature sperm. Our study provides the most extensive data set and annotation of human sperm small RNAs (Pantano et al. RNA. 2015;21:1085-95).
Genomic and proteomic dissection of the human sperm chromatin demonstrates different chromatin domains with a potential epigenetic function 2015-04-02
We have dissected the human sperm chromatin using nucleases into nucleosome-packaged, and protamine-packaged chromatin fractions. Subsequently we have high throughput sequenced the DNA and characterized the proteome of the chromatin domains. Of note we have also detected and high throughput sequenced a subnucleosomal sized fraction. Interestingly the nucleosomal and subnucleosomal fractions were highly enriched at gene promoters and, in addition, some sequences were found to be exclusively associated with one of those. The results of the proteomic analyses demonstrate that there are two distinct sets of sperm proteins which differ in chromatin affinity. Overall our results provide additional support to the possibility that all of these factors may constitute additional layers of sperm epigenetic information (Castillo et al. Mol Hum Reprod. 2014; 20:1041-53)
High throughput sperm differential proteomics suggest that epigenetic alterations contribute to failed assisted reproduction 2014-08-16
The proteins extracted from normozoospermic infertile patients who do not result in pregnancy after IVF were compared to the proteins extracted from normozoospermic patients which resulted in pregnancy after IVF. Tandem mass taq (TMT) labeling and LC-MS/MS proteins quantification allowed detecting 31 proteins present at lower abundance (ratio no pregnancy / pregnancy < 0.67) and 35 at higher abundance (ratio no pregnancy/pregnancy > 1.5) in the no pregnancy group. Bioinformatic analyses showed that the proteins with differing abundance suggest that alterations in the proteins involved in chromatin assembly and metabolism may result in epigenetic errors during spermatogenesis, leading to inaccurate sperm epigenetic signatures, which could ultimately prevent embryonic development. These sperm proteins may thus possibly have clinical relevance (Azpiazu et al., Human Reproduction 2014, 29:1225–37)
The combined human sperm proteome: cellular pathways and implications for basic and clinical science 2013-12-23
We have created a compiled and carefully revised list of 6198 different proteins identified and described in the mature human sperm cell in different studies (Hum Reprod Update 2014;20:40-62). This list represents the most complete sperm proteome available to date. The proteins were assigned to various functional pathways, including metabolism, apoptosis, cell cycle, meiosis and membrane trafficking, among others. Unexpectedly, the sperm cell also contains a range of proteins involved in RNA metabolism and translational regulation, as well as proteins usually located in organelles believed to be absent in sperm, such as cytoplasmatic ribosomes and peroxisomes. Overall the results suggest the presence of several cellular protein pathways previously ignored in the male gamete. Confirming the activity of each of these pathways and understanding their biological significance will certainly boost the knowledge of human sperm and male fertility and infertility in the next years.
Human sperm tail proteome suggests new endogenous metabolic pathways 2012-11-22
We have performed the first comprehensive analysis of the sperm metabolic proteome and our data suggest that sperm is equipped with the enzymatic tools to various pathways usually ignored in sperm. We were surprised with the number of “new” proteins (i.e., not previously described in human sperm) we found. A total of 1049 proteins were identified from the human sperm tail, more than half of which had not been previously described in human sperm. That showed that our approach was indeed very efficient! In addition, we were especially surprised to find out some unexpected proteins. Particularly, the existence of peroxisomal proteins in a cell believed to be devoid of peroxisomes is intriguing! Moreover, we were able to show that sperm might be able to use fatty acids as “fuel” and that lipidic beta oxidation may contribute to sperm motility (which somehow challenges the “sperm energy debate”).Additionally, our outcomes motivate future comparative proteomics studies aimed to settle “what makes a good sperm” (i.e., what distinguishes sperm with better fertilization ability?). Amaral A, Castillo J, Estanyol JM, Ballesca JL, Ramalho-Santos J, Oliva R. Mol Cell Proteomics. 2012 Nov 15. [Epub ahead of print].
Project manager for the FP7 Reproductive Biology Early Research Training (REPRO-TRAIN) initial training network (www.reprotrain.eu) 2012-07-24
This position has been already covered.
10 PhD positions and 4 postdoctoral positions now offered as part of the “Reproductive Biology Early Research Training” (REPROTRAIN), Marie Curie Initial Training Network. 2012-06-19
REPROTRAIN is a Marie Curie Initial Training Network funded by the European Commission under the 7th Framework Programme (FP7-PEOPLE-2011-ITN, PITN-GA-289880). It is composed of 7 strong academic research groups and 2 pharmaceutical companies from 6 different European countries: France, Italy, Netherlands, Germany, UK and Spain. The project coordinator is Rafael Oliva. The network started on January 1st 2012 and will end on December 31st 2015.
Reprotrain aims to provide the key elements to train and update the new generation of researchers with the skills to solve increasingly prevalent problems relating to Male Reproductive Biology and Andrology. We strive to deliver a high standard of multidisciplinary network-wide training to 10 Early Stage Researchers (PhD students) and 4 Experienced Researchers (Postdoctoral Fellows) who will perform studies in genetics and epigenetics, molecular male reproductive medicine, molecular and structural biology and biotechnology. For more information and to apply for one of the available positions see our REPROTRAIN website: reprotrain.eu
Proteomic characterization of the human sperm nucleus identifies 403 different proteins 2011-09-07
More than half (52.6%) of the proteins had not been detected in the previous human whole sperm cell proteome reports. Of relevance, several chromatin-related proteins, such as zinc fingers and transcription factors, so far not known to be associated with the sperm chromatin, have also been detected. For more information see our recently published article in Proteomics (de Mateo et al., 2011)