Proteomic Analysis of Fresh and Liquid-Stored Boar Spermatozoa

Unveiling the power of proteomics in advancing tropical animal health and production

Proteomics, the large-scale study of proteins in biological systems has emerged as a pivotal tool in the field of animal and veterinary sciences, mainly for investigating local and rustic breeds. Proteomics provides valuable insights into biological processes underlying animal growth, reproduction, health, and disease. In this review, we highlight the key proteomics technologies, methodologies, and their applications in domestic animals, particularly in the tropical context. We also discuss advances in proteomics research, including integration of multi-omics data, single-cell proteomics, and proteogenomics, all of which are promising for improving animal health, adaptation, welfare, and productivity. However, proteomics research in domestic animals faces challenges, such as sample preparation variation, data quality control, privacy and ethical considerations relating to animal welfare. We also provide recommendations for overcoming these challenges, emphasizing the importance of following best practices in sample preparation, data quality control, and ethical compliance. We therefore aim for this review to harness the full potential of proteomics in advancing our understanding of animal biology and ultimately improve animal health and productivity in local breeds of diverse animal species in a tropical context.

Cryopreservation modifies the distribution of the prostate-derived lectin SL15 on the llama (Lama glama) sperm

Lectin-like molecules play a key role in mammalian sperm functionality. These multifunctional proteins have been proven to be involved in sperm capacitation, sperm motility, and viability, formation of the oviductal sperm reservoir, and in sperm-oocyte interaction. In a previous study, we reported the presence of a novel seminal plasma lectin, sperm lectin 15 kDa (SL15), adsorbed to the llama sperm. In order to gain knowledge in the understanding of SL15 and its functions, the aims of this study were to (a) elucidate the presence and localization of SL15 in the llama male reproductive tract and sperm, and (b) determine whether the sperm cryopreservation process of cooling and freeze-thawing affects the SL15 levels and distribution on llama sperm. We found that SL15 protein was expressed along the male reproductive system: testis, epididymis, prostate, and bulbourethral glands, being the prostate the main site of SL15 secretion. SL15 was localized on the sperm head, following different localization patterns. In order to understand if sperm cryopreservation induces modifications in the SL15 adsorption pattern, immunocytochemistry and flow cytometry analysis were carried out on fresh, 24 h cooled, and frozen-thawed sperm. Both cooled and frozen sperm showed particular SL15 patterns, that were not observed in the freshly ejaculated, indicating loss of SL15. Flow cytometry analysis also exhibited a decrease of SL15 in the cooled sperm (P < 0.05), whereas a tendency to decrease was found in frozen-thawed sperm (P < 0.1) when compared with freshly ejaculated sperm. This study extends the knowledge about the SL15 in the llama male physiology and provides evidence that cryopreservation-related techniques disrupt SL15 adsorption to the sperm membrane, possibly affecting sperm functionality and fertility.

Proteomics Evaluation of Semen of Clinically Healthy Beagle-Breed Dogs

The objectives of the present work were to evaluate the semen of dogs by means of proteomics methods and to compare with proteomics results of the blood of the animals, in order to increase available knowledge on the topic and present relevant reference values for semen samples. Semen samples were collected from five Beagle-breed dogs. Reproductive assessment of the animals by means of clinical, ultrasonographic and seminological examinations confirmed their reproductive health. The sperm-rich fraction and the prostatic fraction of semen were processed for proteomics evaluation. LC-MS/MS analysis was performed by means of a LTQ Orbitrap Elite system. The technology combines high separation capacity and strong qualitative ability of proteins in biological samples that require deep proteome coverage. Protein classification was performed based on their functional annotations using Gene Ontology (GO). In blood plasma, semen sperm-rich fraction, and semen prostatic fraction, 59, 42 and 43 proteins, respectively, were detected. Two proteins were identified simultaneously in plasma and the semen sperm-rich fraction, 11 proteins in plasma and the semen prostatic fraction, and three proteins in the semen sperm-rich and prostatic fractions. In semen samples, most proteins were related to cell organization and biogenesis, metabolic processes or transport of ions and molecules. Most proteins were located in the cell membrane, the cytosol or the nucleus. Finally, most proteins performed functions related to binding or enzyme regulation. There were no differences between the semen sperm-rich fraction and prostatic fractions in terms of the clustering of proteins. In conclusion, a baseline reference for proteins in the semen of Beagle-breed dogs is provided. These proteins are involved mostly in supporting spermatozoan maturation, survival and motility, enhancing the reproductive performance of male animals. There appears potential for the proteomics examination of semen to become a tool in semen evaluation. This analysis may potentially identify biomarkers for reproductive disorders. This can be particularly useful in stud animals, also given its advantage as a non-invasive method.

Protein Identification of Spermatozoa and Seminal Plasma in Bottlenose Dolphin (Tursiops truncatus)

Proteins play an important role in many reproductive functions such as sperm maturation, sperm transit in the female genital tract or sperm-oocyte interaction. However, in general, little information concerning reproductive features is available in the case of aquatic animals. The present study aims to characterize the proteome of both spermatozoa and seminal plasma of bottlenose dolphins (Tursiops truncatus) as a model organism for cetaceans. Ejaculate samples were obtained from two trained dolphins housed in an aquarium. Spermatozoa and seminal plasma were analyzed by means of proteomic analyses using an LC-MS/MS, and a list with the gene symbols corresponding to each protein was submitted to the DAVID database. Of the 419 proteins identified in spermatozoa and 303 in seminal plasma, 111 proteins were shared by both. Furthermore, 70 proteins were identified as involved in reproductive processes, 39 in spermatozoa, and 31 in seminal plasma. The five most abundant proteins were also identified in these samples: AKAP3, ODF2, TUBB, GSTM3, ROPN1 for spermatozoa and CST11, LTF, ALB, HSP90B1, PIGR for seminal plasma. In conclusion, this study provides the first characterization of the proteome in cetacean sperm and seminal plasma, opening the way to future research into new biomarkers, the analysis of conservation capacity or possible additional applications in the field of assisted reproductive technologies.

Differential Proteomics Analysis of Penaeus vannamei Muscles with Quality Characteristics by TMT Quantitative Proteomics during Low-Temperature Storage

A tandem mass tag technology, based on the quantitative proteomics strategy, was applied to investigate the relationships between proteome changes of Penaeus vannamei (PNVN) muscles and quality characteristics during low-temperature storage. 506 proteins were found as differentially expressed proteins (DEPs) after 10 days of storage under treatments of refrigerated storage (5 °C), ice temperature storage (0 °C), and particle freezing storage (-3 °C) compared with a fresh group (0 day). In addition, Uniprot Knowledgebase (UniprotKB), Gene Ontology enrichment, and Kyoto Encyclopedia of Genes and Genomes were reported. Correlation analysis indicated that nine DEPs were significantly related to quality characteristics-pH, color, and texture. Bioinformatics analysis showed that most of DEPs were involved in binding proteins, metabolic enzyme, and protein turnover. Besides, several DEPs could be good candidate biomarkers of muscle decline. These results could help to further comprehend the proteome changes and mechanisms of the quality decline of PNVN muscles during low-temperature storage.