Spermatozoa of the old endemic rodents of Australia – the possible functional significance of their ventral processes

2014 ◽  
Vol 26 (8) ◽  
pp. 1183 ◽  
Author(s):  
Simon Drew ◽  
Chris Leigh ◽  
William G. Breed
Keyword(s):  
Cell Membrane ◽  
Functional Significance ◽  
In Vitro Study ◽  
Cytoskeletal Proteins ◽  
Sperm Transport ◽  
Apical Hook ◽  
Sperm Binding ◽  
Initial Penetration ◽  
Egg Coat

Spermatozoa of the plains mouse (Pseudomys australis), like those of most Australian old endemic rodents, contain, in addition to an apical hook, two further processes that extend from the upper concave surface of the head, the ventral processes. This study shows that these processes contain thiol-rich cytoskeletal proteins, which presumably help to maintain their rigidity during sperm transport, together with the overlying cell membrane having abundant intramembranous proteins. To determine the possible functional significance of these processes, an in vitro study of spermatozoon–zona binding was undertaken. The findings suggest that initial sperm binding occurs by way of the cell membrane over the acrosome of the apical hook and that, subsequently, the lateral surfaces of the ventral processes also become tightly bound to the zona matrix. These ventral processes may therefore have evolved to increase sperm adhesion to the outer zona surface and/or to enhance stabilisation of the spermatozoon at the time of zona binding and initial penetration of the egg coat.

The Degree of Resistance of Erythrocyte Membrane Cytoskeletal Proteins to Supra-Physiologic Concentrations of Calcium: An In Vitro Study

2014 ◽  
Vol 247 (8) ◽  
pp. 695-701 ◽  
Author(s):  
Ebrahim Mostafavi ◽  
Arash Aghajani Nargesi ◽  
Zaniar Ghazizadeh ◽  
Mehrdad Larry ◽  
Roya Horabad Farahani ◽  
...  
Keyword(s):  
Erythrocyte Membrane ◽  
In Vitro Study ◽  
Cytoskeletal Proteins ◽  
Vitro Study

An In Vitro Study on Adjuvant Enhanced Irreversible Electroporation

2012 ◽  
Author(s):  
Chunlan Jiang ◽  
Zhenpeng Qin ◽  
Gary Long ◽  
John C. Bischof
Keyword(s):  
Cell Death ◽  
Cell Membrane ◽  
Thermal Injury ◽  
Irreversible Electroporation ◽  
Membrane Integrity ◽  
In Vitro Study ◽  
Connective Tissues ◽  
Careful Choice ◽  
Electrical Pulses

Recently, irreversible electroporation (IRE) has emerged as a promising tumor ablation technique. IRE induces cell death by irreversibly compromising membrane integrity with a series of short, high voltage electrical pulses [1]. IRE offers many advantages over surgery and thermal ablations including that it 1) is fast and minimally invasive, 2) destroys the tumor while preserving adjacent connective tissues [2], and 3) can be delivered with negligible thermal injury [3]. Here we hypothesize that the thresholds necessary to successfully electroporate cancer cell membranes, and therefore more effectively destroy an entire tumor, can be dramatically improved by careful choice of 1) electroporation parameter, and 2) chemical adjuvants that specifically impact the cell membrane.

scholarly journals Mice expressing aberrant sperm-specific protein PMIS2 produce normal-looking but fertilization-incompetent spermatozoa

2012 ◽  
Vol 23 (14) ◽  
pp. 2671-2679 ◽  
Author(s):  
Ryo Yamaguchi ◽  
Yoshitaka Fujihara ◽  
Masahito Ikawa ◽  
Masaru Okabe
Keyword(s):  
Zona Pellucida ◽  
Cumulus Cells ◽  
Specific Protein ◽  
Aberrant Expression ◽  
Sperm Transport ◽  
Vitro Fertilization ◽  
Sperm Binding ◽  
Sperm Membrane ◽  
Domain 3

Eight kinds of gene-disrupted mice (Clgn, Calr3, Pdilt, Tpst2, Ace, Adam1a, Adam2, and Adam3) show impaired sperm transition into the oviducts and defective sperm binding to the zona pellucida. All of these knockout strains are reported to lack or show aberrant expression of a disintegrin and metallopeptidase domain 3 (ADAM3) on the sperm membrane. We performed proteomic analyses of the proteins of these infertile spermatozoa to clarify whether the abnormal function is caused exclusively by a deficiency in ADAM3 expression. Two proteins, named PMIS1 and PMIS2, were missing in spermatozoa from Clgn-disrupted mice. To study their roles, we generated two gene-disrupted mouse lines. Pmis1-knockout mice were fertile, but Pmis2-knockout males were sterile because of a failure of sperm transport into the oviducts. Pmis2-deficient spermatozoa also failed to bind to the zona pellucida. However, they showed normal fertilizing ability when eggs surrounded with cumulus cells were used for in vitro fertilization. Further analysis revealed that these spermatozoa lacked the ADAM3 protein, but the amount of PMIS2 was also severely reduced in Adam3-deficient spermatozoa. These results suggest that PMIS2 might function both as the ultimate factor regulating sperm transport into the oviducts and in modulating sperm–zona binding.

scholarly journals Identification of Sperm-Binding Sites in the N-Terminal Domain of Bovine Egg Coat Glycoprotein ZP4

2022 ◽  
Vol 23 (2) ◽  
pp. 762
Author(s):  
Kamila Dilimulati ◽  
Misaki Orita ◽  
Yoshiki Yonahara ◽  
Fabiana Lica Imai ◽  
Naoto Yonezawa
Keyword(s):  
Binding Sites ◽  
Binding Activity ◽  
Binding Region ◽  
Terminal Domain ◽  
Sperm Binding ◽  
Bovine Sperm ◽  
Selective Interaction ◽  
Egg Coat

The species-selective interaction between sperm and egg at the beginning of mammalian fertilisation is partly mediated by a transparent envelope called the zona pellucida (ZP). The ZP is composed of three or four glycoproteins (ZP1–ZP4). The functions of the three proteins present in mice (ZP1–ZP3) have been extensively studied. However, the biological role of ZP4, which was found in all other mammals studied so far, has remained largely unknown. Previously, by developing a solid support assay system, we showed that ZP4 exhibits sperm-binding activity in bovines and the N-terminal domain of bovine ZP4 (bZP4 ZP-N1 domain) is a sperm-binding region. Here, we show that bovine sperm bind to the bZP4 ZP-N1 domain in a species-selective manner and that N-glycosylation is not required for sperm-binding activity. Moreover, we identified three sites involved in sperm binding (site I: from Gln-41 to Pro-46, site II: from Leu-65 to Ser-68 and site III: from Thr-108 to Ile-123) in the bZP4 ZP-N1 domain using chimeric bovine/porcine and bovine/human ZP4 recombinant proteins. These results provide in vitro experimental evidence for the role of the bZP4 ZP-N1 domain in mediating sperm binding to the ZP.

scholarly journals A Model In Vitro Study Using Hypericin: Tumor-Versus Necrosis-Targeting Property and Possible Mechanisms

Biology ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 13 ◽  
Author(s):  
Yue Li ◽  
Shuncong Wang ◽  
Yuanyu Zhao ◽  
Hexige Saiyin ◽  
Xiaoyan He ◽  
...  
Keyword(s):  
Energy Metabolism ◽  
Confocal Microscopy ◽  
Cell Membrane ◽  
Cell Lines ◽  
Fluorescence Intensity ◽  
Subcellular Distribution ◽  
In Vitro Study ◽  
Vitro Study ◽  
Binding Theory

Hypericin (Hyp) had been explored as a tumor-seeking agent for years; however, more recent studies showed its necrosis-avidity rather than cancer-seeking property. To further look into this discrepancy, we conducted an in vitro study on Hyp retention in vital and dead cancerous HepG2 and normal LO2 cell lines by measuring the fluorescence intensity and concentration of Hyp in cells. To question the DNA binding theory for its necrosis-avidity, the subcellular distribution of Hyp was also investigated to explore the possible mechanisms of the necrosis avidity. The fluorescence intensity and concentration are significantly higher in dead cells than those in vital cells, and this difference did not differ between HepG2 and LO2 cell lines. Hyp was taken up in vital cells in the early phase and excreted within hours, whereas it was retained in dead cells for more than two days. Confocal microscopy showed that Hyp selectively accumulated in lysosomes rather than cell membrane or nuclei. Hyp showed a necrosis-avid property rather than cancer-targetability. The long-lasting retention of Hyp in dead cells may be associated with halted energy metabolism and/or binding with certain degraded cellular substrates. Necrosis-avidity of Hyp was confirmed, which may be associated with halted energy metabolism in dead LO2 or HepG2 cells.

scholarly journals In-vitro study of monocytic THP-1 leukemia cell membrane elasticity with a single-cell microfluidic-assisted optical trapping system

2020 ◽  
Vol 11 (10) ◽  
pp. 6027
Author(s):  
Ric John L. Ombid ◽  
Glenn G. Oyong ◽  
Esperanza C. Cabrera ◽  
Wilfred V. Espulgar ◽  
Masato Saito ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Single Cell ◽  
Optical Trapping ◽  
Leukemia Cell ◽  
In Vitro Study ◽  
Vitro Study ◽  
Membrane Elasticity
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