O-118 Activation of mouse oocytes with human sperm extract increases fertilization rates after injection of immotile mature sperm and nuclei isolated from round spermatids

1997 ◽  
Vol 68 ◽  
pp. S59-S60
Author(s):  
O Lacham-Kaplan ◽  
Y Ohkuma ◽  
A Trounson
1991 ◽  
Vol 99 (1) ◽  
pp. 157-165
Author(s):  
R.K. Naz ◽  
K. Ahmad ◽  
R. Kumar

The monoclonal anti-phosphotyrosine antibody (PTA) recognized proteins related to relative molecular mass regions of 94,000 +/− 3000 and 46,000 +/− 3000 Mr on Western blots of detergent-solubilized non-capacitated human sperm extract (HSE). The pattern of phosphorylation at tyrosine residues depended upon the physiological state of the sperm cells. At least six protein bands corresponding to four molecular regions of 94,000 +/− 3000, 46,000 +/− 3000, 25,000 +/− 7000 and 12,000 +/− 2000 Mr, respectively, were labeled with 32P when human sperm were capacitated in vitro; the proteins belonging to the former three regions were phosphotyrosine proteins as they were precipitable by PTA. In vitro kinase assay performed directly on HSE indicated autophosphorylation of proteins of the same four molecular regions, with the capacitated sperm preparations having 30% higher 32P incorporation into 94,000 +/− 3000 Mr proteins and 17% less incorporation into 12,000 +/− 2000 Mr proteins as compared to the non-capacitated sperm preparations. Both of these protein regions were also autophosphorylated at tyrosine residues when immunoprecipitated phosphotyrosine proteins were used for the kinase assay. Phosphorylation of tyrosine residues of 94,000 +/− 3000 Mr proteins was further stimulated by 1.38- to 1.46-fold in response to exposure to zona pellucida proteins, namely the porcine ZP3 and human zona proteins (HZP); the HZP induced the highest response. Immunofluorescence observations on fixed human sperm demonstrated that capacitation as well as exposure to zona proteins increased the degree of tyrosine-specific fluorescence per sperm cell as well as the number of sperm cells that showed fluorescence at the acrosomal region of the spermhead.(ABSTRACT TRUNCATED AT 250 WORDS)


2019 ◽  
Vol 34 (7) ◽  
pp. 1186-1194 ◽  
Author(s):  
Yi-min Cheng ◽  
Xiao-nian Hu ◽  
Zhen Peng ◽  
Ting-ting Pan ◽  
Fang Wang ◽  
...  

AbstractSTUDY QUESTIONIs there a role for lysine glutarylation (Kglu), a newly identified protein post-translational modification (PTM), in human sperm?SUMMARY ANSWERKglu occurs in several proteins located in the tail of human sperm, and it was reduced in asthenozoospermic (A) men and positively correlated with progressive motility of human sperm, indicating its important role in maintaining sperm motility.WHAT IS KNOWN ALREADYSince mature sperm are almost transcriptionally silent, PTM is regarded as an important pathway in regulating sperm function. However, only phosphorylation has been extensively studied in mature sperm to date. Protein lysine modification (PLM), a hot spot of PTMs, was rarely studied except for a few reports on lysine methylation and acetylation. As a newly identified PLM, Kglu has not been well characterized, especially in mature sperm.STUDY DESIGN, SIZE, DURATIONSperm samples were obtained from normozoospermic (N) men and A men who visited the reproductive medical center between February 2016 and January 2018. In total, 61 N men and 59 A men were recruited to participate in the study.PARTICIPANTS/MATERIALS, SETTING, METHODSKglu was examined by immunoblotting and immunofluorescence assays using a previously qualified pan-anti-glutaryllysine antibody that recognizes glutaryllysine in a wide range of sequence contexts (both in histones and non-histone substrates) but not the structurally similar malonyllysine and succinyllysine. The immunofluorescence assay was imaged using laser scanning confocal microscopy and super-resolution structured illumination microscopy. Sperm motility parameters were examined by computer-assisted sperm analysis.MAIN RESULTS AND THE ROLE OF CHANCEKglu occurs in several proteins (20–150 kDa) located in the tail of human sperm, especially in the middle piece and the latter part of the principal piece. Sperm Kglu was modulated by regulatory systems (enzymes and glutaryl-CoA) similar to those in HeLa cells. The mean level of sperm Kglu was significantly reduced in A men compared with N men (P < 0.001) and was positively correlated with progressive motility (P < 0.001). The sodium glutarate-induced elevation of Kglu levels in A men with lower Kglu levels in sperm significantly improved the progressive motility (P < 0.001). Furthermore, the reduced sperm Kglu levels in A men was accompanied by an increase in sperm glutaryl-CoA dehydrogenase (a regulatory enzyme of Kglu).LARGE SCALE DATAN/ALIMITATIONS, REASONS FOR CAUTIONAlthough the present study indicated the involvement of sperm Kglu in maintaining progressive motility of human sperm, the underlying mechanism needs to be investigated further.WIDER IMPLICATIONS OF THE FINDINGSThe findings of this study provide an insight into the novel role of Kglu in human sperm and suggest that abnormality of sperm PLMs may be one of the causes of asthenozoospermia.STUDY FUNDING/COMPETING INTEREST(S)National Natural Science Foundation of China (81 771 644 to T.L.; 31 671 204 to X.Z. and 81 871 207 to H.C.); National Basic Research Program of China (973 Program, 2015CB943003 to X.Z.); Natural Science Foundation of Jiangxi, China (20171ACB21006 and 20161BAB204167 to T.L.; 20165BCB18001 to X.Z.). The authors have no conflicts of interest to declare.


Reproduction ◽  
2015 ◽  
Vol 150 (4) ◽  
pp. 257-268 ◽  
Author(s):  
Yuchuan Zhou ◽  
Yanfei Ru ◽  
Huijuan Shi ◽  
Yanjiao Wang ◽  
Bin Wu ◽  
...  

Cholecystokinin (CCK), a peptide hormone and a neurotransmitter, was detected in mature sperm two decades ago. However, the exact role of CCK and the types of CCK receptors (now termed CCK1 and CCK2) in sperm have not been identified. Here, we find that CCK1 and CCK2 receptors are immunolocalized to the acrosomal region of mature sperm. The antagonist of CCK1 or CCK2 receptor strongly activated the soluble adenylyl cyclase/cAMP/protein kinase A signaling pathway that drives sperm capacitation-associated protein tyrosine phosphorylation in dose- and time-dependent manners. But these actions of stimulation were abolished when sperm were incubated in the medium in the absence of HCO3−. Further investigation demonstrated that the inhibitor of CCK1 or CCK2 receptor could accelerate the uptake of HCO3−and significantly elevate the intracellular pH of sperm. Interestingly, the synthetic octapeptide of CCK (CCK8) showed the same action and mechanism as antagonists of CCK receptors. Moreover, CCK8 and the antagonist of CCK1 or CCK2 receptor were also able to accelerate human sperm capacitation-associated protein tyrosine phosphorylation by stimulating the influx of HCO3−. Thus, the present results suggest that CCK and its receptors may regulate sperm capacitation-associated protein tyrosine phosphorylation by modulating the uptake of HCO3−.


Zygote ◽  
2004 ◽  
Vol 12 (2) ◽  
pp. 95-103 ◽  
Author(s):  
Hugo Díaz ◽  
Pedro Esponda

The cortical cytoplasm and cortical granules (CGs) of mouse oocytes were analysed by electron microscopy. Oocytes were collected soon and 20 h after ovulation from adult young females (3–4 months old). In addition, gametes collected soon after ovulation from 12- to 14-month-old females were used. Ultrastructural analyses were undertaken using the conventional procedures and the alcoholic PTA method. PTA selectively stains the CGs indicating the presence of lysine-rich proteins in these granules. Oocytes from young females showed CGs as dense granules 300–500 nm in diameter linearly arranged under the oolemma. In oocytes recovered 20 h after ovulation 24.31% of CGs appeared vacuolated and 38.40% internalized in the cytoplasm. In gametes collected from old females several changes were observed in the cortical cytoplasm: (a) CGs appeared concentrated in some areas while others regions were devoid of granules; (b) groups of CGs appeared internalized in the egg cytoplasm; (c) the CG contents had swollen and changed, showing dense and clear areas; (d) numerous dense structures and vesicles (lysosome-like vesicles) were present; (e) cytoplasmic fragmentation was frequently seen. Fragments contained CGs, dense structures and vacuoles. These changes are closely related to the low fertilization rates shown by these oocytes when they were used for in vitro fertilization procedures.


2005 ◽  
Vol 20 (5) ◽  
pp. 1244-1247 ◽  
Author(s):  
Yasuyuki Araki ◽  
Midori Yoshizawa ◽  
Yasuhisa Araki

2016 ◽  
Vol 62 (2) ◽  
pp. 125-132 ◽  
Author(s):  
Hoda Rajabi ◽  
Homa Mohseni-Kouchesfehani ◽  
Abdollah Mohammadi-Sangcheshmeh ◽  
Fattaneh Farifteh-Nobijari ◽  
Mohammad Salehi

2016 ◽  
Vol 33 (6) ◽  
pp. 747-756 ◽  
Author(s):  
Anna Ferrer-Vaquer ◽  
Montserrat Barragan ◽  
Thomas Freour ◽  
Valérie Vernaeve ◽  
Rita Vassena

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