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Keywords = sperm guidance

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14 pages, 5874 KiB  
Article
Multi-Omics Sequencing Dissects the Atlas of Seminal Plasma Exosomes from Semen Containing Low or High Rates of Sperm with Cytoplasmic Droplets
by Zilu Zhang, Xiaoxian Xu, Fumei Chen, Qingyou Liu, Zhili Li, Xibang Zheng and Yunxiang Zhao
Int. J. Mol. Sci. 2025, 26(3), 1096; https://doi.org/10.3390/ijms26031096 - 27 Jan 2025
Cited by 1 | Viewed by 1075
Abstract
Sperm cytoplasmic droplets (CDs) are remnants of cytoplasm that can cause a number of problems if it not shed from the sperm after ejaculation. Exosomes can rapidly bind to sperm, but it is not clear whether exosomes can affect the migration and shedding [...] Read more.
Sperm cytoplasmic droplets (CDs) are remnants of cytoplasm that can cause a number of problems if it not shed from the sperm after ejaculation. Exosomes can rapidly bind to sperm, but it is not clear whether exosomes can affect the migration and shedding of CDs. We first extracted and characterized seminal plasma exosomes from boar semen containing sperm with low or high rates of CDs. Then, the transcriptomic and proteomic detection of these exosomes were performed to analyze the differences between the two groups of seminal plasma exosomes. The results revealed that 486 differentially expressed genes (DEGs), 40 differentially expressed proteins (DEPs), and 503 differentially expressed lncRNAs (DElncRNAs) were identified between the low CD rate group and high CD rate group. Integrative multi-omics analysis showed that exosome components may affect migration and shedding of cytoplasmic droplets by influencing cytoskeletal regulation and insulin signaling, including regulation of the actin cytoskeleton, ECM–receptor interaction, axon guidance, insulin secretion, and the insulin signaling pathway. Overall, our study systematically revealed the DEGs, DEPs, and DElncRNAs in seminal plasma exosomes between low CD rate semen and high CD rate semen, which will help broaden our understanding of the complex molecular mechanisms involved in the shedding of CDs. Full article
(This article belongs to the Section Molecular Informatics)
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9 pages, 1139 KiB  
Article
Methionine Improves Boar Sperm Quality by Promoting Mitochondrial Translation during Liquid Storage
by Meiling Tan, Yuting Zhao, Li Ren, Chenxuan Li, Jiangxue Cai and Bin He
Animals 2024, 14(15), 2227; https://doi.org/10.3390/ani14152227 - 31 Jul 2024
Cited by 2 | Viewed by 1555
Abstract
Boar sperm quality serves as an important indicator of reproductive efficiency, playing a direct role in enhancing the output of livestock production. It has been demonstrated that mitochondrial protein translation is present in sperm and plays a crucial role in regulating sperm motility, [...] Read more.
Boar sperm quality serves as an important indicator of reproductive efficiency, playing a direct role in enhancing the output of livestock production. It has been demonstrated that mitochondrial protein translation is present in sperm and plays a crucial role in regulating sperm motility, capacitation and in vitro fertilization rate. The present study aimed to determine whether methionine supplementation enhances mitochondrial translation in boar sperm, thereby improving sperm quality. The results showed a significant elevation in the abundance of mitochondrial methionyl-tRNA formyltransferase (MTFMT), a crucial enzyme for mitochondrial protein translation, and mitochondrial DNA-encoded cytochrome c oxidase subunit 1 (COX1) in boar sperm exhibiting high motility. Both amino acids and methionine supplementation significantly enhanced boar sperm motility during storage. Moreover, methionine supplementation mitigates the loss of acrosomal integrity, enhances the expression of COX1, and boosts mitochondrial activity. Furthermore, the positive impact of methionine was negated in the presence of the mitochondrial translation inhibitor chloramphenicol. Together, these findings suggest that boar sperm may utilize methionine as a protein translation substrate to enhance sperm motility by stimulating mitochondrial protein translation. The supplementation of methionine may enhance the quality of boar sperm, thereby providing guidance for the optimization of diluent formulations for liquid storage and the identification of physiological regulators that regulate sperm motility. Full article
(This article belongs to the Section Pigs)
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13 pages, 269 KiB  
Review
The Role of Artificial Intelligence in Male Infertility: Evaluation and Treatment: A Narrative Review
by Nikit Venishetty, Marwan Alkassis and Omer Raheem
Uro 2024, 4(2), 23-35; https://doi.org/10.3390/uro4020003 - 25 Mar 2024
Cited by 7 | Viewed by 4979
Abstract
Male infertility has affected an increasingly large population over the past few decades, affecting over 186 million people globally. The advent of assisted reproductive technologies (ARTs) and artificial intelligence (AI) has changed the landscape of diagnosis and treatment of male infertility. Through an [...] Read more.
Male infertility has affected an increasingly large population over the past few decades, affecting over 186 million people globally. The advent of assisted reproductive technologies (ARTs) and artificial intelligence (AI) has changed the landscape of diagnosis and treatment of male infertility. Through an extensive literature review encompassing the PubMed, Google Scholar, and Scopus databases, various AI techniques such as machine learning (ML), artificial neural networks (ANNs), deep learning (DL), and natural language processing (NLP) were examined in the context of evaluating seminal quality, predicting fertility potential, and improving semen analysis. Research indicates that AI models can accurately estimate the quality of semen, diagnose problems with sperm, and provide guidance on reproductive health decisions. In addition, developments in smartphone-based semen analyzers and computer-assisted semen analysis (CASA) are indicative of initiatives to improve the price, portability, and accuracy of results. Future directions point to possible uses for AI in ultrasonography assessment, microsurgical testicular sperm extraction (microTESE), and home-based semen analysis. Overall, AI holds significant promise in revolutionizing the diagnosis and treatment of male infertility, offering standardized, objective, and efficient approaches to addressing this global health challenge. Full article
(This article belongs to the Special Issue Male Infertility—Diagnosis and Treatment)
12 pages, 6649 KiB  
Article
Microplastic Abundance in Rainbow Trout Life Cycle: Step by Step
by Gonca Alak, Mine Köktürk, Muhammed Atamanalp, Esat Mahmut Kocaman, Arzu Ucar, Nurinisa Esenbuğa, Sinan Özcan and Veysel Parlak
Sustainability 2023, 15(19), 14255; https://doi.org/10.3390/su151914255 - 27 Sep 2023
Cited by 7 | Viewed by 2029
Abstract
In recent years, with the encouragement of national and international authorities, researchers on plastic levels in aquaculture have begun to assess consumer health risks as well as ecological monitoring. Based on this guidance, the aim of this study is to determine the microplastic [...] Read more.
In recent years, with the encouragement of national and international authorities, researchers on plastic levels in aquaculture have begun to assess consumer health risks as well as ecological monitoring. Based on this guidance, the aim of this study is to determine the microplastic load of rainbow trout raised under routine breeding conditions without an external treatment in all developmental stages from egg to +1 year of age. Sperm, egg, fertilized egg, eyed egg, alevin or such fry, and swimming fry on growing stock (1-year-old) stages of cultured fish and commercial feeds were used for the following stages: 300–500 µm, 500–800 µm, 800–1200 µm, 1 mm, 2 mm, 3 mm, 4 mm, and 5 mm. The samples were collected to determine the presence of microplastic (MP) and at which stage of this life cycle the MP has entered into the system intensively. The obtained findings showed that the total amount of MP determined in the stages without feed intake was 14 pieces, and this value increased by 557% (total of 92-piece MP) in fish that started external feeding. While no significant difference was found between the MP amounts in different feed groups, the dominant microplastic color in the feed groups was black and blue, and the polymer type was polyethylene. This general modelling, in which MP concentrations are determined in all life cycles from egg to adult in a cultured fish species, including in the given feeds, will encourage further research. Current findings have shown that any outsourced input used during growing periods can cause MP contamination to the end of fish production, processing, and storage. Full article
(This article belongs to the Section Sustainable Agriculture)
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8 pages, 546 KiB  
Perspective
Discussing the Sexual Health Impacts of Electronic Cigarette Use with Youth: A Proposed Framework to Support Urologists
by Nilanga Aki Bandara, Dhruv Lalkiya, Abdullah Alhamam and Kourosh Afshar
Future 2023, 1(2), 38-45; https://doi.org/10.3390/future1020006 - 31 Aug 2023
Viewed by 2833
Abstract
The sexual health of young people during the youth age period is of utmost importance, as it sets the stage for sexual well-being over the life course. In addition to the existing challenges that youth face concerning their sexual health, electronic cigarettes may [...] Read more.
The sexual health of young people during the youth age period is of utmost importance, as it sets the stage for sexual well-being over the life course. In addition to the existing challenges that youth face concerning their sexual health, electronic cigarettes may also negatively impact their sexual well-being. Specifically, through issues such as stuttering priapism, reduced sperm quality and quantity, and erectile dysfunction. Electronic cigarette use among youth is prevalent. Therefore, given the negative sexual health impacts associated with electronic cigarette use, coupled with the prevalent use of electronic cigarettes, it is necessary for youth to receive adequate support and guidance, so they understand the potential impacts that electronic cigarette use can have on their sexual well-being. Urologists are uniquely situated to play an important role in supporting the sexual health of youth, given their medical and surgical knowledge, however, it appears that they do not receive adequate training to carry out discussions about sexual health with youth. This paper aims to support urologists to have discussions with youth patients on the impact that electronic cigarettes have on their sexual health through a proposed four-step framework. This four-step framework involves: (i) establishing the relationship, (ii) assessing current electronic cigarette use, (iii) sharing research examining the impact of electronic cigarettes on sexual health, and (iv) discussing strategies to prevent/reduce or stop electronic cigarette use. It is necessary to acknowledge that this framework is only a small component of efforts to educate youth on the impacts that electronic cigarettes have on their sexual health. Moving forward, implementation and evaluation of this framework is needed. Full article
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19 pages, 3088 KiB  
Article
Impaired Testicular Function without Altering Testosterone Concentration Using an Anti-Follicular-Stimulating Hormone Receptor (Anti-FSHr) Single-Chain Variable Fragment (scFv) in Long-Tailed Macaques (Macaca fascicularis)
by Pakpoom Navanukraw, Sroisuda Chotimanukul, Taratorn Kemthong, Kiattawee Choowongkomon and Kaywalee Chatdarong
Animals 2023, 13(14), 2282; https://doi.org/10.3390/ani13142282 - 12 Jul 2023
Cited by 2 | Viewed by 2171
Abstract
FSHr antibodies have been shown to inhibit the differentiation of spermatogonia to primary spermatocytes, resulting in infertility without a pathological effect on reproductive organs. The aim of this study was to develop single-chain variable fragments (scFvs) against the follicular-stimulating hormone receptor (anti-FSHr) using [...] Read more.
FSHr antibodies have been shown to inhibit the differentiation of spermatogonia to primary spermatocytes, resulting in infertility without a pathological effect on reproductive organs. The aim of this study was to develop single-chain variable fragments (scFvs) against the follicular-stimulating hormone receptor (anti-FSHr) using phage-display technology and to evaluate the effects of intratesticular administration of the anti-FSHr scFv on testicular function and testosterone production. A phage clone against the extracellular domain of FSHr selected from a scFv phagemid library was analyzed for binding kinetics by surface plasmon resonance. Using ultrasound guidance, three adult macaques (M. fascicularis) were administered with 1 mL of 0.4 mg/mL anti-FSHr scFv (treatment) and 1 mL sterile phosphate buffer solution (control) into the left and right rete testis, respectively. Testicular appearance and volume, ejaculate quality, and serum testosterone levels were recorded on day 0 (before injection) and on days 7, 28, and 56 (after injection). Testicular tissue biopsies were performed on day 7 and day 56 to quantify the mRNA expressions of androgen binding protein (ABP), inhibin subunit beta B (IHBB), and vascular endothelial growth factor A (VEGFA). The results demonstrated that the anti-FSHr scFv molecule was calculated as 27 kDa with a dissociation constant (KD) of 1.03 µM. The volume of the anti-FSHr scFv-injected testicle was reduced on days 28 and 56 compared with day 0 (p < 0.05). Total sperm number was reduced from day 0 (36.4 × 106 cells) to day 56 (1.6 × 106 cells) (p < 0.05). The percentage of sperm motility decreased from day 0 (81.7 ± 1.0%) to day 7 (23.3 ± 1.9%), day 28 (41.7 ± 53.4%), and day 56 (8.3 ± 1.9%) (p < 0.05). Sperm viability on day 0 was 86.8 ± 0.5%, which reduced to 64.2 ± 1.5%, 67.1 ± 2.2%, and 9.3 ± 1.1% on days 7, 28, and 56, respectively (p < 0.05). The expression of ABP and VEGFA on days 7 (14.2- and 3.2-fold) and 56 (5.6- and 5.5-fold) was less in the scFv-treated testicle compared with the controls (p < 0.05). On day 56, the expression of IHBB was less (p < 0.05) in the treated testis (1.3-fold) compared with the controls. Serum testosterone levels were unchanged throughout the study period (p > 0.05). This study characterized the anti-FSHr scFv and demonstrated that treatment with anti-FSHr ameliorates testicular function without altering testosterone levels, offering a potential alternative contraceptive for the long-tailed macaques. Full article
(This article belongs to the Section Animal Reproduction)
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12 pages, 1781 KiB  
Article
Complete Cycle Mapping Using a Quantitative At-Home Hormone Monitoring System in Prediction of Fertile Days, Confirmation of Ovulation, and Screening for Ovulation Issues Preventing Conception
by Andrea K. Wegrzynowicz, Amy Beckley, Aimee Eyvazzadeh, Gary Levy, John Park and Joshua Klein
Medicina 2022, 58(12), 1853; https://doi.org/10.3390/medicina58121853 - 15 Dec 2022
Cited by 9 | Viewed by 9185
Abstract
Background and Objectives: To achieve pregnancy, it is highly beneficial to identify the time of ovulation as well as the greater period of fertile days during which sperm may survive leading up to ovulation. Confirming successful ovulation is also critical to accurately diagnose [...] Read more.
Background and Objectives: To achieve pregnancy, it is highly beneficial to identify the time of ovulation as well as the greater period of fertile days during which sperm may survive leading up to ovulation. Confirming successful ovulation is also critical to accurately diagnose ovulatory disorders. Ovulation predictor kits, fertility monitors, and tracking apps are all available to assist with detecting ovulation, but often fall short. They may not detect the full fertile window, provide accurate or real-time information, or are simply expensive and impractical. Finally, few over-the-counter products provide information to women about their ovarian reserve and future fertility. Therefore, there is a need for an easy, over-the-counter, at-home quantitative hormone monitoring system that assesses ovarian reserve, predicts the entire fertile window, and can screen for ovulatory disorders. Materials and Methods: Proov Complete is a four-in-one at-home multihormone testing system that utilizes lateral flow assay test strips paired with the free Proov Insight App to guide testing of four hormones—FSH, E1G, LH, and PdG—across the woman’s cycle. In a pilot study, 40 women (including 16 with a fertility-related diagnosis or using fertility treatments) used Complete for one cycle. Results: Here, we demonstrate that Proov Complete can accurately and sensitively predict ovarian reserve, detect up to 6 fertile days and confirm if ovulation was successful, in one easy-to-use kit. Ovulation was confirmed in 38 cycles with a detectable PdG rise. An average of 5.3 fertile days (from E1G rise to PdG rise) were detected, with an average of 2.7 days prior to LH surge. Ovulation was confirmed via PdG rise an average of 2.6 days following the LH surge. While 38/40 women had a PdG rise, only 22 had a sustained PdG level above 5 μg/mL throughout the critical implantation window, indicating ovulatory dysfunction in 16 women. Conclusions: Proov Complete can detect the entire fertile window of up to 6 fertile days and confirm ovulation, while also providing information on ovarian reserve and guidance to clinicians and patients. Full article
(This article belongs to the Special Issue Quantitative Hormone Monitoring of the Menstrual Cycle)
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19 pages, 854 KiB  
Review
Perspectives on Potential Fatty Acid Modulations of Motility Associated Human Sperm Ion Channels
by Akila Cooray, Ji Hyun Kim, Mee Ree Chae, Sungwon Lee and Kyu Pil Lee
Int. J. Mol. Sci. 2022, 23(7), 3718; https://doi.org/10.3390/ijms23073718 - 28 Mar 2022
Cited by 15 | Viewed by 3429
Abstract
Human spermatozoan ion channels are specifically distributed in the spermatozoan membrane, contribute to sperm motility, and are associated with male reproductive abnormalities. Calcium, potassium, protons, sodium, and chloride are the main ions that are regulated across this membrane, and their intracellular concentrations are [...] Read more.
Human spermatozoan ion channels are specifically distributed in the spermatozoan membrane, contribute to sperm motility, and are associated with male reproductive abnormalities. Calcium, potassium, protons, sodium, and chloride are the main ions that are regulated across this membrane, and their intracellular concentrations are crucial for sperm motility. Fatty acids (FAs) affect sperm quality parameters, reproductive pathologies, male fertility, and regulate ion channel functions in other cells. However, to date the literature is insufficient to draw any conclusions regarding the effects of FAs on human spermatozoan ion channels. Here, we aimed to discern the possible effects of FAs on spermatozoan ion channels and direct guidance for future research. After investigating the effects of FAs on characteristics related to human spermatozoan motility, reproductive pathologies, and the modulation of similar ion channels in other cells by FAs, we extrapolated polyunsaturated FAs (PUFAs) to have the highest potency in modulating sperm ion channels to increase sperm motility. Of the PUFAs, the ω-3 unsaturated fatty acids have the greatest effect. We speculate that saturated and monounsaturated FAs will have little to no effect on sperm ion channel activity, though the possible effects could be opposite to those of the PUFAs, considering the differences between FA structure and behavior. Full article
(This article belongs to the Section Molecular Biology)
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13 pages, 2132 KiB  
Review
Sperm-Guiding Unconventional Prostaglandins in C. elegans: Synthesis and Signaling
by Ekta Tiwary, Muhan Hu and Jeevan K. Prasain
Metabolites 2021, 11(12), 853; https://doi.org/10.3390/metabo11120853 - 8 Dec 2021
Cited by 5 | Viewed by 5506
Abstract
Prostaglandins comprise a family of lipid signaling molecules derived from polyunsaturated fatty acids and are involved in a wide array of biological processes, including fertilization. Prostaglandin-endoperoxide synthase (a.k.a. cyclooxygenase or Cox) initiates prostaglandin synthesis from 20-carbon polyunsaturated fatty acids, such as arachidonic acid. [...] Read more.
Prostaglandins comprise a family of lipid signaling molecules derived from polyunsaturated fatty acids and are involved in a wide array of biological processes, including fertilization. Prostaglandin-endoperoxide synthase (a.k.a. cyclooxygenase or Cox) initiates prostaglandin synthesis from 20-carbon polyunsaturated fatty acids, such as arachidonic acid. Oocytes of Caenorhabditis elegans (C. elegans) have been shown to secrete sperm-guidance cues prostaglandins, independent of Cox enzymes. Both prostaglandin synthesis and signal transduction in C. elegans are environmentally modulated pathways that regulate sperm guidance to the fertilization site. Environmental factors such as food triggers insulin and TGF-β secretion and their levels regulate tissue-specific prostaglandin synthesis in C. elegans. This novel PG pathway is abundant in mouse and human ovarian follicular fluid, where their functions, mechanism of synthesis and pathways remain to be established. Given the importance of prostaglandins in reproductive processes, a better understanding of how diets and other environmental factors influence their synthesis and function may lead to new strategies towards improving fertility in mammals. Full article
(This article belongs to the Special Issue Metabolism and Reproduction)
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17 pages, 1784 KiB  
Review
Signaling at Physical Barriers during Pollen–Pistil Interactions
by Kayleigh J. Robichaux and Ian S. Wallace
Int. J. Mol. Sci. 2021, 22(22), 12230; https://doi.org/10.3390/ijms222212230 - 12 Nov 2021
Cited by 13 | Viewed by 4706
Abstract
In angiosperms, double fertilization requires pollen tubes to transport non-motile sperm to distant egg cells housed in a specialized female structure known as the pistil, mediating the ultimate fusion between male and female gametes. During this journey, the pollen tube encounters numerous physical [...] Read more.
In angiosperms, double fertilization requires pollen tubes to transport non-motile sperm to distant egg cells housed in a specialized female structure known as the pistil, mediating the ultimate fusion between male and female gametes. During this journey, the pollen tube encounters numerous physical barriers that must be mechanically circumvented, including the penetration of the stigmatic papillae, style, transmitting tract, and synergid cells as well as the ultimate fusion of sperm cells to the egg or central cell. Additionally, the pollen tube must maintain structural integrity in these compact environments, while responding to positional guidance cues that lead the pollen tube to its destination. Here, we discuss the nature of these physical barriers as well as efforts to genetically and cellularly identify the factors that allow pollen tubes to successfully, specifically, and quickly circumnavigate them. Full article
(This article belongs to the Special Issue Pollen-Pistil Interaction)
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15 pages, 3704 KiB  
Article
Novel Mutations in X-Linked, USP26-Induced Asthenoteratozoospermia and Male Infertility
by Chunyu Liu, Ying Shen, Qunshan Shen, Wen Zhang, Jiaxiong Wang, Shuyan Tang, Huan Wu, Shixiong Tian, Jiangshan Cong, Xiaojin He, Li Jin, Feng Zhang, Xiaohui Jiang and Yunxia Cao
Cells 2021, 10(7), 1594; https://doi.org/10.3390/cells10071594 - 25 Jun 2021
Cited by 12 | Viewed by 3810
Abstract
Male infertility is a multifactorial disease with a strong genetic background. Abnormal sperm morphologies have been found to be closely related to male infertility. Here, we conducted whole-exome sequencing in a cohort of 150 Han Chinese men with asthenoteratozoospermia. Two novel hemizygous mutations [...] Read more.
Male infertility is a multifactorial disease with a strong genetic background. Abnormal sperm morphologies have been found to be closely related to male infertility. Here, we conducted whole-exome sequencing in a cohort of 150 Han Chinese men with asthenoteratozoospermia. Two novel hemizygous mutations were identified in USP26, an X-linked gene preferentially expressed in the testis and encoding a deubiquitinating enzyme. These USP26 variants are extremely rare in human population genome databases and have been predicted to be deleterious by multiple bioinformatics tools. Hematoxylin-eosin staining and electron microscopy analyses of the spermatozoa from men harboring hemizygous USP26 variants showed a highly aberrant morphology and ultrastructure of the sperm heads and flagella. Real-time quantitative PCR and immunoblotting assays revealed obviously reduced levels of USP26 mRNA and protein in the spermatozoa from men harboring hemizygous deleterious variants of USP26. Furthermore, intracytoplasmic sperm injections performed on infertile men harboring hemizygous USP26 variants achieved satisfactory outcomes. Overall, our study demonstrates that USP26 is essential for normal sperm morphogenesis, and hemizygous USP26 mutations can induce X-linked asthenoteratozoospermia. These findings will provide effective guidance for the genetic and reproductive counseling of infertile men with asthenoteratozoospermia. Full article
(This article belongs to the Section Intracellular and Plasma Membranes)
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13 pages, 1240 KiB  
Review
Paving the Way for Fertilization: The Role of the Transmitting Tract
by Ana Marta Pereira, Diana Moreira, Sílvia Coimbra and Simona Masiero
Int. J. Mol. Sci. 2021, 22(5), 2603; https://doi.org/10.3390/ijms22052603 - 5 Mar 2021
Cited by 20 | Viewed by 4474
Abstract
Angiosperm reproduction relies on the precise growth of the pollen tube through different pistil tissues carrying two sperm cells into the ovules’ embryo sac, where they fuse with the egg and the central cell to accomplish double fertilization and ultimately initiate seed development. [...] Read more.
Angiosperm reproduction relies on the precise growth of the pollen tube through different pistil tissues carrying two sperm cells into the ovules’ embryo sac, where they fuse with the egg and the central cell to accomplish double fertilization and ultimately initiate seed development. A network of intrinsic and tightly regulated communication and signaling cascades, which mediate continuous interactions between the pollen tube and the sporophytic and gametophytic female tissues, ensures the fast and meticulous growth of pollen tubes along the pistil, until it reaches the ovule embryo sac. Most of the pollen tube growth occurs in a specialized tissue—the transmitting tract—connecting the stigma, the style, and the ovary. This tissue is composed of highly secretory cells responsible for producing an extensive extracellular matrix. This multifaceted matrix is proposed to support and provide nutrition and adhesion for pollen tube growth and guidance. Insights pertaining to the mechanisms that underlie these processes remain sparse due to the difficulty of accessing and manipulating the female sporophytic tissues enclosed in the pistil. Here, we summarize the current knowledge on this key step of reproduction in flowering plants with special emphasis on the female transmitting tract tissue. Full article
(This article belongs to the Special Issue Signaling in Plant Reproduction)
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24 pages, 4292 KiB  
Article
Insights into the Mechanism of Bovine Spermiogenesis Based on Comparative Transcriptomic Studies
by Xin Li, Chenying Duan, Ruyi Li and Dong Wang
Animals 2021, 11(1), 80; https://doi.org/10.3390/ani11010080 - 5 Jan 2021
Cited by 6 | Viewed by 4158
Abstract
To reduce subfertility caused by low semen quality and provide theoretical guidance for the eradication of human male infertility, we sequenced the bovine transcriptomes of round, elongated spermatids and epididymal sperms. The differential analysis was carried out with the reference of the mouse [...] Read more.
To reduce subfertility caused by low semen quality and provide theoretical guidance for the eradication of human male infertility, we sequenced the bovine transcriptomes of round, elongated spermatids and epididymal sperms. The differential analysis was carried out with the reference of the mouse transcriptome, and the homology trends of gene expression to the mouse were also analysed. First, to explore the physiological mechanism of spermiogenesis that profoundly affects semen quality, homological trends of differential genes were compared during spermiogenesis in dairy cattle and mice. Next, Gene Ontology (GO), Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway enrichment, protein–protein interaction network (PPI network), and bioinformatics analyses were performed to uncover the regulation network of acrosome formation during the transition from round to elongated spermatids. In addition, processes that regulate gene expression during spermiogenesis from elongated spermatid to epididymal sperm, such as ubiquitination, acetylation, deacetylation, and glycosylation, and the functional ART3 gene may play important roles during spermiogenesis. Therefore, its localisation in the seminiferous tubules and epididymal sperm were investigated using immunofluorescent analysis, and its structure and function were also predicted. Our findings provide a deeper understanding of the process of spermiogenesis, which involves acrosome formation, histone replacement, and the fine regulation of gene expression. Full article
(This article belongs to the Special Issue Reproduction in Dairy Cattle)
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18 pages, 979 KiB  
Article
Selection of Boar Sperm by Reproductive Biofluids as Chemoattractants
by Luis Alberto Vieira, Alessia Diana, Cristina Soriano-Úbeda and Carmen Matás
Animals 2021, 11(1), 53; https://doi.org/10.3390/ani11010053 - 30 Dec 2020
Cited by 5 | Viewed by 3265
Abstract
Chemotaxis is a spermatozoa guidance mechanism demonstrated in vitro in several mammalian species including porcine. This work focused on follicular fluid (FF), periovulatory oviductal fluid (pOF), the medium surrounding oocytes during in vitro maturation (conditioned medium; CM), progesterone (P4), and the combination of [...] Read more.
Chemotaxis is a spermatozoa guidance mechanism demonstrated in vitro in several mammalian species including porcine. This work focused on follicular fluid (FF), periovulatory oviductal fluid (pOF), the medium surrounding oocytes during in vitro maturation (conditioned medium; CM), progesterone (P4), and the combination of those biofluids (Σ) as chemotactic agents and modulators of spermatozoa fertility in vitro. A chemotaxis chamber was designed consisting of two independent wells, A and B, connected by a tube. The spermatozoa are deposited in well A, and the chemoattractants in well B. The concentrations of biofluids that attracted a higher proportion of spermatozoa to well B were 0.25% FF, 0.25% OF, 0.06% CM, 10 pM P4 and 0.25% of a combination of biofluids (Σ2), which attracted between 3.3 and 12.3% of spermatozoa (p < 0.05). The motility of spermatozoa recovered in well B was determined and the chemotactic potential when the sperm calcium channel CatSper was inhibited, which significantly reduced the % of spermatozoa attracted (p < 0.05). Regarding the in vitro fertility, the spermatozoa attracted by FF produced higher rates of penetration of oocytes and development of expanded blastocysts. In conclusion, porcine reproductive biofluids show an in vitro chemotactic effect on spermatozoa and modulate their fertilizing potential. Full article
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30 pages, 1962 KiB  
Review
Signalling Pinpointed to the Tip: The Complex Regulatory Network That Allows Pollen Tube Growth
by Patricia Scholz, Jannis Anstatt, Hannah Elisa Krawczyk and Till Ischebeck
Plants 2020, 9(9), 1098; https://doi.org/10.3390/plants9091098 - 26 Aug 2020
Cited by 32 | Viewed by 6532
Abstract
Plants display a complex life cycle, alternating between haploid and diploid generations. During fertilisation, the haploid sperm cells are delivered to the female gametophyte by pollen tubes, specialised structures elongating by tip growth, which is based on an equilibrium between cell wall-reinforcing processes [...] Read more.
Plants display a complex life cycle, alternating between haploid and diploid generations. During fertilisation, the haploid sperm cells are delivered to the female gametophyte by pollen tubes, specialised structures elongating by tip growth, which is based on an equilibrium between cell wall-reinforcing processes and turgor-driven expansion. One important factor of this equilibrium is the rate of pectin secretion mediated and regulated by factors including the exocyst complex and small G proteins. Critically important are also non-proteinaceous molecules comprising protons, calcium ions, reactive oxygen species (ROS), and signalling lipids. Among the latter, phosphatidylinositol 4,5-bisphosphate and the kinases involved in its formation have been assigned important functions. The negatively charged headgroup of this lipid serves as an interaction point at the apical plasma membrane for partners such as the exocyst complex, thereby polarising the cell and its secretion processes. Another important signalling lipid is phosphatidic acid (PA), that can either be formed by the combination of phospholipases C and diacylglycerol kinases or by phospholipases D. It further fine-tunes pollen tube growth, for example by regulating ROS formation. How the individual signalling cues are intertwined or how external guidance cues are integrated to facilitate directional growth remain open questions. Full article
(This article belongs to the Special Issue Pollen Tube)
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