Crystalline-like structure in sperm membrane of Chinese Rhodeus sinensis, Acheilognathinae

Author(s):  
Ting-Lu Guan ◽  
Yi Yang

It is well know that the spermatozoa are highly polarized cells. The membrane of mammals sperm have been studied in detail. The results have shown are markable diversity of structure with in an otherwise common place unit membrane. However, very few papers were dealt with teleost sperm membrane. Our privious report shows that Carassius auratus (Cyprinidae) sperm membrane have differentiated with regional specificity just like those in mammals. In general, intramembrane protein particles are highly organized at certain are as in the head plasma membrane forming crystalline-like structure, in contrast, rest areas of plasma membrane contain many random dispersed particles. The present study has shown the existence as well as the characteristics of crystalline-like structure in sperm membrane of Chinese Rhodeus sinensis, Acheilognathinae, Cyprinidae.In spawing season the male fish are killed, apart of test is were took out and put into 2.5% glutaraldehyde buffered to pH 7.2 with 0.1mol/L sodium cacodylate.

Author(s):  
N. Seki ◽  
Y. Toyama ◽  
T. Nagano

It is believed that i ntramembra.nous sterols play an essential role in membrane stability and permeability. To investigate the distribution changes of sterols in sperm membrane during epididymal maturation and capacitation, filipin has been used as a cytochemical probe for the detection for membrane sterols. Using this technique in combination with freeze fracturing, we examined the boar spermatozoa under various physiological conditions.The spermatozoa were collected from: 1) caput, corpus and cauda epididymides, 2) sperm rich fraction of ejaculates, and 3)the uterus 2hr after natural coition. They were fixed with 2.5% glutaraldehyde in 0.05M cacodylate buffer (pH 7.4), and treated with the filipin solution (final concentration : 0.02.0.05%) for 24hr at 4°C with constant agitation. After the filipin treatment, replicas were made by conventional freeze-fracture technique. The density of filipin-sterol complexes (FSCs) was determined in the E face of the plasma membrane of head regions.


Development ◽  
1991 ◽  
Vol 113 (1) ◽  
pp. 141-149 ◽  
Author(s):  
S. Mortillo ◽  
P.M. Wassarman

Egg zona pellucida glycoproteins mZP3 and mZP2 serve as primary and secondary sperm receptors, respectively, during initial stages of fertilization in mice [Wassarman (1988) A. Rev. Biochem. 57, 415–442]. These receptors interact with complementary egg-binding proteins (EBPs) located on the sperm surface to support species-specific gamete adhesion. Results of whole-mount autoradiographic experiments suggest that purified egg mZP3 and mZP2 bind preferentially to acrosome-intact (AI) and acrosome-reacted (AR) sperm heads, respectively [Bleil and Wassarman (1986) J. Cell Biol. 102, 1363–1371]. Here, we used purified egg mZP2, egg mZP3 and fetuin, which were coupled directly to colloidal gold (‘gold-probes’), to examine binding of these glycoproteins to membrane compartments of AI and AR sperm by transmission electron microscopy. mZP3 gold-probes were found associated primarily with plasma membrane overlying the acrosomal and post-acrosomal regions of AI sperm heads. They were also found associated with plasma membrane overlying the post-acrosomal region of AR sperm heads. mZP2 gold-probes were found associated primarily with inner acrosomal membrane of AR sperm heads, although some gold was associated with outer acrosomal membrane of AI sperm that had holes in plasma membrane overlying the acrosome. Fetuin gold-probes, used to assess background levels of binding, were bound at relatively low levels to plasma membrane and inner acrosomal membrane of AI and AR sperm, respectively. None of the gold-probes exhibited significant binding to sperm tails, or to red blood cells and residual bodies present in sperm preparations. These results provide further evidence that mZP2 and mZP3 bind preferentially to heads of AR and AI sperm, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)


2016 ◽  
Vol 68 (3) ◽  
pp. 620-628 ◽  
Author(s):  
L.S.L.S. Reis ◽  
A.A. Ramos ◽  
A.S. Camargos ◽  
E. Oba

ABSTRACT This study evaluated the plasma membrane integrity, acrosomal membrane integrity, and mitochondrial membrane potential of Nelore bull sperm from early puberty to early sexual maturity and their associations with sperm motility and vigor, the mass motility of the spermatozoa (wave motion), scrotal circumference, and testosterone. Sixty Nelore bulls aged 18 to 19 months were divided into four lots (n=15 bulls/lot) and evaluated over 280 days. Semen samples, collected every 56 days by electroejaculation, were evaluated soon after collection for motility, vigor and wave motion under an optical microscope. Sperm membrane integrity, acrosomal integrity, and mitochondrial activity were evaluated under a fluorescent microscope using probe association (FITC-PSA, PI, JC-1, H342). The sperm were classified into eight integrity categories depending on whether they exhibited intact or damaged membranes, an intact or damaged acrosomal membrane, and high or low mitochondrial potential. The results show that bulls have a low amount of sperm with intact membranes at puberty, and the sperm show low motility, vigor, and wave motion; however, in bulls at early sexual maturity, the integrity of the sperm membrane increased significantly. The rate of sperm membrane damage was negatively correlated with motility, vigor, wave motion, and testosterone in the bulls, and a positive correlation existed between sperm plasma membrane integrity and scrotal circumference. The integrity of the acrosomal membrane was not influenced by puberty. During puberty and into early sexual maturity, bulls show low sperm mitochondrial potential, but when bulls reached sexual maturity, high membrane integrity with high mitochondrial potential was evident.


1979 ◽  
Vol 81 (1) ◽  
pp. 229-253 ◽  
Author(s):  
L G Tilney ◽  
J G Clain ◽  
M S Tilney

The membranes of Limulus (horseshoe crab) sperm were examined before and during the acrosomal reaction by using the technique of freeze-fracturing and thin sectioning. We focused on three areas. First, we examined stages in the fusion of the acrosomal vacuole with the cell surface. Fusion takes place in a particle-free zone which is surrounded by a circlet of particles on the P face of the plasma membrane and an underlying circlet of particles on the P face of the acrosomal vauole membrane. These circlets of particles are present before induction. Up to nine focal points of fusion occur within the particle-free zone. Second, we describe a system of fine filaments, each 30 A in diameter, which lies between the acrosomal vacuole and the plasma membrane. These filaments change their orientation as the vacuole opens, a process that takes place in less than 50 ms. Membrane particles seen on the P face of the acrosomal vacuole membrane change their orientation at the same time and in the same way as do the filaments, thus indicating that the membrane particles and filaments are probably connected. Third, we examined the source and the point of fusion of new membrane needed to cover the acrosomal process. This new membrane is almost certainly derived from the outer nuclear envelope and appears to insert into the plasma membrane in a particle-free area adjacent to an area rich in particles. The latter is the region where the particles are probably connected to the cytoplasmic filaments. The relevance of these observations in relation to the process of fertilization of this fantastic sperm is discussed.


Author(s):  
B. Ch. Behboodi

IntroductionBorder bodies or lomasomes are the aggregation of membranes and vesicles located between the plasma membrane and the cell wall of many fungi, algae, and higher plants. Despite extensive investigation, the biogenesis as well as function of these structures is not yet known. The purpose of this investigation was to describe the biogenesis of lomasomes in Armillaria mellea and to provide some observations on their function related to cell wall formation.Materials and MethodsVarious thalli of fungi as non-aggregated hyphae, pseudosclerotes, rhizomorphs and carpophores were grown either on orange or synthetic media as described previously. The thalli were fixed in 4% glutaraldehyde buffered with 0.1 M sodium cacodylate (pH 7.4), and 0.15 M sucrose for 4 h at 4°. They were postfixed with 1% osmium tetroxide in the same buffer for 2 h at 4° and embedded in Epon according to the Luft procedure. Cytochemical studies using thiocarbohydrazide-silver proteinate were performed according the Thiéry.


2021 ◽  
Author(s):  
Wenfeng Xiong ◽  
Chunling Shen ◽  
Chaojie Li ◽  
Xiaohong Zhang ◽  
Haoyang Ge ◽  
...  

A disintegrin and metalloproteinase 3 (ADAM3) is a sperm membrane protein critical for sperm migration from the uterus into the oviduct and sperm-egg binding in mice. Disruption of PRSS37 results in male infertility concurrent with the absence of mature ADAM3 from cauda epididymal sperm. However, how PRSS37 modulates ADAM3 maturation remains largely unclear. Here, we determine PRSS37 interactome by GFP immunoprecipitation coupled with mass spectrometry in PRSS37-EGFP knock-in mice. Three molecular chaperones (CLGN, CALR3 and PDILT) and three ADAM proteins (ADAM2, ADAM6B and ADAM4) were identified to be interacting with PRSS37. Coincidently, five of them (except ADAM4) have been reported to interact with precursor ADAM3 and regulate its maturation. We further demonstrated that PRSS37 also interacts directly with precursor ADAM3 and its deficiency impedes the association between PDILT and ADAM3. This could contribute to improper translocation of ADAM3 to the germ cell surface, leading to ADAM3 loss in PRSS37 null mature sperm. The understanding of the maturation mechanisms of pivotal sperm plasma membrane proteins will pave the way toward novel strategies for contraception and treatment of unexplained male infertility.


2013 ◽  
Vol 25 (1) ◽  
pp. 158
Author(s):  
F. P. Hartwig ◽  
F. P. Lisboa ◽  
G. A. Monteiro ◽  
R. R. D. Maziero ◽  
M. A. Alvarenga ◽  
...  

Artificial insemination with cooled-shipped semen has been widely used in horse breeding. However, some stallions, referred to as poor coolers, present abrupt fertility decrease when their semen is processed, cooled, and transported. Cholesterol incorporation into sperm membranes improves the quality of cryopreserved semen by increasing the sperm membrane stability and fluidity at low temperatures. Despite the beneficial effect of cholesterol addition on sperm quality, studies demonstrate that the presence of large amounts of cholesterol in the plasma membrane interferes with the physiological process of sperm capacitation and is detrimental to frozen equine sperm fertility. The aim of this study was to assess the fertility of cooled semen from good-cooler and poor-cooler stallions after adding cholesterol to sperm membranes. Two stallions were used and classified as good cooler (n = 1) and poor cooler (n = 1) based on the ability to maintain sperm progressive motility after 24 h of cooling at 5°C. For classification of the stallions, the fertility history was also taken into account through the results of pregnancy per cycle using inseminations with cooled semen (<50% for poor cooler and >70% for good cooler). Ejaculates of these stallions were subjected to 2 treatments: control (CON) and cholesterol (CLC). In the CON group, the semen was extended to 30 × 106 sperms mL–1 with skim milk-based extender (BotuSemen™). In the CLC group, the semen was extended as in the CON group plus 0.25 µL/1 × 106 sperms of 6.1 mM cholesterol-loaded cyclodextrin was added. Afterwards, both treatments were cooled at 5°C for 24 h. To test the fertility of poor-cooler and good-cooler stallions, 2 cycles from 25 mares and 2 cycles from 10 mares were respectively used. For both stallions, randomly for each mare, the inseminations were performed by alternating both treatments. If the mare was first inseminated with the CLC treatment, in the next cycle the CON treatment was used and vice versa. After 24 h of ovulation induction, the inseminations were done in the uterine body with 1 × 109 viable cells. Statistical analyses were performed using the Fisher exact test and significance was set at P < 0.05. For the poor cooler, the CON treatment presented 44% pregnancy/cycle compared to 76% for the CLC treatment (11/25a v. 19/25b). For the good cooler, both treatments presented 80% (8/10) pregnancy/cycle. The results suggest that the fertility capability of stallions is not affected by incorporation of cholesterol-loaded cyclodextrin to the sperm plasma membrane. Additionally, the utilization of cholesterol-loaded cyclodextrin may be an option to enable the utilization of cooled-shipped semen from poor cooler stallions for AI programs.


2014 ◽  
Vol 26 (5) ◽  
pp. 725 ◽  
Author(s):  
Olga García-Álvarez ◽  
Alejandro Maroto-Morales ◽  
Manuel Ramón ◽  
Enrique del Olmo ◽  
Pilar Jiménez-Rabadán ◽  
...  

The present study evaluated modifications occurring in thawed ram spermatozoa during incubation in different media that supported in vitro capacitation and fertilisation, and examines how these changes relate to IVF. Thawed sperm samples were incubated under capacitating (Cap) and non-capacitating (non-Cap) conditions for 0, 1 and 2 h and used in an IVF test. During incubation, changes related to membrane status and the motility pattern of spermatozoa were assessed, the latter being used to characterise sperm subpopulations. A significantly greater increase (P ≤ 0.05) in the percentage of spermatozoa with higher membrane fluidity was observed in samples incubated with Cap medium from the beginning of incubation. In addition, changes over time in the distribution of the motile subpopulation were particularly evident when spermatozoa were incubated with Cap medium, with a noted increase in spermatozoa classified as ‘hyperactivated like’, with major changes occurring after 1 h incubation. Both characteristics (i.e. membrane fluidity and the percentage of the hyperactivated-like subpopulation) were significantly related with in vitro fertility, and only sperm samples incubated with the Cap medium were capable of fertilising oocytes. These results support the idea that changes in sperm membrane fluidity and motility pattern (i.e. an increase in hyperactivated spermatozoa) are needed for fertilisation to take place.


Author(s):  
Dang Liankai

With the developing process from the spermatid to the sperm, the great changes of membrane structure are token place both in plasma membrane and nuclear membrane. This note will report the development of polarization in membrane and the distribution of nuclear pores and protein particles during spermiogenesis, and also compare the number of protein in P-face with that in E-face.Mice, Rats, Rabbits and Dogs were operated by taking out the seminiferous tube. It was fixed in 2.5% glutaradehyde for 2 hrs 5 washed in cacodylated buffer, and then the sample was put in to 30% glycerol solution for 6-12hrs. Samples were put into liquid nitrogen rapidly and afterwards moved to BALZAR BAF-400D instrument to get Freeze-Fracture replica and double replica for observation with TEM.The expression and the development of the polarization in membrane structure of the spermatid. The spermatid in different stepshas different characteristics and there is more polarization for membrane structure following spermiogenesis.


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