Sperm surface changes and their consequences for sperm transit through the female reproductive tract

2020 ◽  
Vol 150 ◽  
pp. 96-105
Author(s):  
J.P. Rickard ◽  
S.P. de Graaf
Keyword(s):  
Reproductive Tract ◽  
Female Reproductive Tract ◽  
Sperm Surface ◽  
Surface Changes

178. THE CHAPERONIN CONTAINING TCP-1 (CCT/TRiC) MULTISUBUNIT COMPLEX IS INVOLVED IN MEDIATING SPERM - OOCYTE INTERACTIONS

2010 ◽  
Vol 22 (9) ◽  
pp. 96
Author(s):  
M. D. Dun ◽  
R. Aitken ◽  
B. Nixon
Keyword(s):  
Zona Pellucida ◽  
Reproductive Tract ◽  
Protein Complexes ◽  
Female Reproductive Tract ◽  
Mass Spectrometry Analysis ◽  
Spectrometry Analysis ◽  
Sperm Surface ◽  
Collective Data ◽  
Concomitant Reduction ◽  
Future Work

Mammalian spermatozoa only express their capacity for fertilization following capacitation, a process characterized by a suite of biophysical and biochemical changes that occurs as the cells ascend the female reproductive tract. A key event associated with the attainment of a capacitated state is a dramatic reorganization of the sperm surface architecture to render these cells competent to bind to the protective matrix of the oocyte, the zona pellucida. Our previous analysis of these remodeling events has provided compelling evidence that they include the assembly and/or presentation of multimeric protein complexes on the sperm surface. In addition, we have demonstrated that at least two of these complexes possess strong affinity for solubilized zona pellucida. In our current study we have utilised mass spectrometry analysis to reveal that one of these complexes comprises the eight subunits that form a composite, multimeric structure known as the chaperonin containing TCP-1 (CCT/TRiC) complex. Our collective data suggest that this complex participates indirectly in zona pellucida interaction, possibly through the conveyance of key zona adhesion molecules to the sperm surface during capacitation. Consistent with this notion, we were able to demonstrate that the sperm CCT/TRiC complex releases its bound substrates upon exposure to ATP, and this treatment induced a significant, concomitant reduction in the ability of capacitated sperm to bind to the zona pellucida. Furthermore, the use of immunoprecipitation assays confirmed the interaction of the CCT/TRiC complex with at least one putative zona pellucida receptor candidate, namely zona pellucida binding protein 2 (ZPBP2). Future work is now aimed at identifying additional zona receptors that may reside within this complex and the pathways that regulate its functional assembly.

scholarly journals Unusual interplay of contrasting selective pressures on β-defensin genes implicated in male fertility of the Buffalo (Bubalus bubalis)

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Vipul Batra ◽  
Avinash Maheshwarappa ◽  
Komal Dagar ◽  
Sandeep Kumar ◽  
Apoorva Soni ◽  
...  
Keyword(s):  
Reproductive Tract ◽  
Mammalian Species ◽  
Sequence Divergence ◽  
Bubalus Bubalis ◽  
Spatial Variations ◽  
Female Reproductive Tract ◽  
Surface Binding ◽  
Reproductive Tissues ◽  
Sperm Surface ◽  
Molecular Functions

Abstract Background The buffalo, despite its superior milk-producing ability, suffers from reproductive limitations that constrain its lifetime productivity. Male sub-fertility, manifested as low conception rates (CRs), is a major concern in buffaloes. The epididymal sperm surface-binding proteins which participate in the sperm surface remodelling (SSR) events affect the survival and performance of the spermatozoa in the female reproductive tract (FRT). A mutation in an epididymal secreted protein, beta-defensin 126 (DEFB-126/BD-126), a class-A beta-defensin (CA-BD), resulted in decreased CRs in human cohorts across the globe. To better understand the role of CA-BDs in buffalo reproduction, this study aimed to identify the BD genes for characterization of the selection pressure(s) acting on them, and to identify the most abundant CA-BD transcript in the buffalo male reproductive tract (MRT) for predicting its reproductive functional significance. Results Despite the low protein sequence homology with their orthologs, the CA-BDs have maintained the molecular framework and the structural core vital to their biological functions. Their coding-sequences in ruminants revealed evidence of pervasive purifying and episodic diversifying selection pressures. The buffalo CA-BD genes were expressed in the major reproductive and non-reproductive tissues exhibiting spatial variations. The Buffalo BD-129 (BuBD-129) was the most abundant and the longest CA-BD in the distal-MRT segments and was predicted to be heavily O-glycosylated. Conclusions The maintenance of the structural core, despite the sequence divergence, indicated the conservation of the molecular functions of the CA-BDs. The expression of the buffalo CA-BDs in both the distal-MRT segments and non-reproductive tissues indicate the retention the primordial microbicidal activity, which was also predicted by in silico sequence analyses. However, the observed spatial variations in their expression across the MRT hint at their region-specific roles. Their comparison across mammalian species revealed a pattern in which the various CA-BDs appeared to follow dissimilar evolutionary paths. This pattern appears to maintain only the highly efficacious CA-BD alleles and diversify their functional repertoire in the ruminants. Our preliminary results and analyses indicated that BuBD-129 could be the functional ortholog of the primate DEFB-126. Further studies are warranted to assess its molecular functions to elucidate its role in immunity, reproduction and fertility.

168. IDENTIFICATION AND CHARACTERISATION OF SURFACE PROTEIN COMPLEXES IN HUMAN SPERMATOZOA

2009 ◽  
Vol 21 (9) ◽  
pp. 86
Author(s):  
K. A. Redgrove ◽  
E. A. McLaughlin ◽  
M. K. O'Bryan ◽  
R. J. Aitken ◽  
B. Nixon
Keyword(s):  
Zona Pellucida ◽  
Reproductive Tract ◽  
Protein Complexes ◽  
Polyacrylamide Gel Electrophoresis ◽  
Human Sperm ◽  
Female Reproductive Tract ◽  
Human Spermatozoa ◽  
20S Proteasome ◽  
Sperm Surface ◽  
Final Maturation

Upon leaving the testis mammalian spermatozoa are functionally incompetent and are thus unable to fertilize an oocyte. As the spermatozoa ascend the female reproductive tract, functional maturity is achieved through a complex cascade of biophysical and biochemical changes known as capacitation. An important aspect of this final maturation phase is the remodelling of the sperm surface architecture to enable it to interact with the zona pellucida, a glycoprotein matrix that surrounds the oocyte, and initiate fertilisation. While originally thought to be underpinned by a simple lock and key mechanism, emerging evidence has suggested that this interaction may instead be mediated by a multimeric recognition complex that is formed on the sperm surface during capacitation. However, to date the presence and composition of such a complex has yet to be described. Through the application of Blue Native Polyacrylamide Gel Electrophoresis (BN-PAGE), we have provided evidence that human spermatozoa express a number of high molecular weight protein complexes on their surface. Furthermore, the affinity of these surface expressed complexes for the zona pellucida was assessed utilising solubilised human zona pellucida and the technique of Far Western Blotting. Among the complexes that showed affinity for the zona pellucida we identified one comprising 14 subunits of the 20S proteasome. Interestingly, the 20S proteasome has previously been implicated in various aspects of mammalian fertilisation, including zona pellucida penetration and the acrosome reaction, although its precise role in these events has yet to be elucidated. Collectively, these results demonstrate the presence of multimeric protein complexes on the surface of human spermatozoa, and support their putative role in the initial interaction between the sperm and the zona pellucida. Our current research is focused on elucidation of the role of the 20S proteasome in human sperm-zona binding and further investigation of surface expressed protein complexes.

Effect of Contraceptive Steroids on the Endometrium of Guinea Pig: SEM study

1977 ◽  
Vol 35 ◽  
pp. 668-669
Author(s):  
Mai M. Said ◽  
Ramesh K. Nayak ◽  
Randall E. McCoy
Keyword(s):  
Guinea Pig ◽  
Reproductive Tract ◽  
Three Dimensional ◽  
Female Reproductive Tract ◽  
Human Female ◽  
Surface Ultrastructure ◽  
Transmission Electron ◽  
Sem Study ◽  
Uterine Mucosa ◽  
Group 1

Burgos and Wislocki described changes in the mucosa of the guinea pig uterus, cervix and vagina during the estrous cycle investigated by transmission electron microscopy. More recently, Moghissi and Reame reported the effects of progestational agents on the human female reproductive tract. They found drooping and shortening of cilia in norgestrel and norethindrone- treated endometria. To the best of our knowledge, no studies concerning the effects of mestranol and norethindrone given concurrently on the three-dimensional surface features on the uterine mucosa of the guinea pig have been reported. The purpose of this study was to determine the effect of mestranol and norethindrone on surface ultrastructure of guinea pig uterus by SEM.Seventy eight animals were used in this study. They were allocated into two groups. Group 1 (20 animals) was injected intramuscularly 0.1 ml vegetable oil and served as controls.

Surface ultrastructure of danazol treated rat endometrium: A SEM study

1983 ◽  
Vol 41 ◽  
pp. 556-557
Author(s):  
R.P. Apkarian ◽  
J.S. Sanfilippo
Keyword(s):  
Cross Sections ◽  
Reproductive Tract ◽  
Preliminary Investigation ◽  
Breast Disease ◽  
Distal Segment ◽  
Uterine Horn ◽  
Female Reproductive Tract ◽  
Ultrastructural Changes ◽  
Cycle Phase ◽  
Sprague Dawley

The synthetic androgen danazol, is an isoxazol derivative of ethisterone. It is utilized in the treatment of endometriosis, fibrocystic breast disease, and has a potential use as a contraceptive. A study was designed to evaluate the ultrastructural changes associated with danazol therapy in a rat model. The preliminary investigation of the distal segment of the rat uterine horn was undertaken as part of a larger study intended to elucidate the effects of danazol on the female reproductive tract.Cross-sections (2-3 mm in length) of the distal segment of the uterine horn from sixteen Sprague-Dawley rats were prepared for SEM. Ten rats in estrus served as controls and six danazol treated rats were noted to have alterations of the estrus cycle i.e. a lag in cycle phase or noncycling patterns. Specimens were fixed in 3% glutaraldehyde in 0.05M phosphate buffer containing CaCl2 at pH 7.0-7.4 and chilled to 4°C. After a brief wash in distilled water, specimens were passed through a graded series of ethanol, critical point dryed in CO2 from absolute ethanol, and coated with 6nm Au. Observations were made with an IS1-40 SEM operated at 15kV.

The application of electron microscopy to diagnosis in gynecologic neoplasms and tumor-like conditions

1984 ◽  
Vol 42 ◽  
pp. 102-105
Author(s):  
Lawrence M. Roth
Keyword(s):  
Electron Microscopy ◽  
Reproductive Tract ◽  
Malignant Tumors ◽  
Frozen Section ◽  
Cost Effective ◽  
Female Reproductive Tract ◽  
Ultrastructural Examination ◽  
Specific Diagnosis ◽  
Potential Value ◽  
Gynecologic Neoplasms

The female reproductive tract may be the site of a wide variety of benign and malignant tumors, as well as non-neoplastic tumor-like conditions, most of which can be diagnosed by light microscopic examination including special stains and more recently immunoperoxidase techniques. Nevertheless there are situations where ultrastructural examination can contribute substantially to an accurate and specific diagnosis. It is my opinion that electron microscopy can be of greatest benefit and is most cost effective when applied in conjunction with other methodologies. Thus, I have developed an approach which has proved useful for me and may have benefit for others. In cases where it is deemed of potential value, glutaraldehyde-fixed material is obtained at the time of frozen section or otherwise at operation. Coordination with the gynecologic oncologist is required in the latter situation. This material is processed and blocked and is available if a future need arises.

Sign in / Sign up

Export Citation Format

Share Document