Aim: To explore the possible mechanisms of male infertility caused by antisperm antibody (AsAb). Methods: Thesoluble interleukin-2 receptor (sIL-2R) level in serum was analyzed by ELISA and Na^+ -K^+ -exchanging ATPas...Aim: To explore the possible mechanisms of male infertility caused by antisperm antibody (AsAb). Methods: Thesoluble interleukin-2 receptor (sIL-2R) level in serum was analyzed by ELISA and Na^+ -K^+ -exchanging ATPase activi-ty in semen by phosphorus (Pi) assay. Results: The slL-2R level in serum was significantly higher and the Na^+ -K^+ -exchanging ATPase activity in semen significantly lower in AsAb positive infertile men when compared with thecontrols. Conclusion: The AsAb titer varies with the slL-2R level in serum. A decrease in Na^+ -K^+ -exchangingATPase activity in semen may play a role in male infertility caused by AsAb.展开更多
A bstract Na + /K +-ATPases are membrane-associated enzymes responsible for the active transport of Na + and K + ions across cell membranes, generating chemical and electrical gradients. These enzymes' α-subunit ...A bstract Na + /K +-ATPases are membrane-associated enzymes responsible for the active transport of Na + and K + ions across cell membranes, generating chemical and electrical gradients. These enzymes' α-subunit provides catalytic function, binding and hydrolyzing ATP, and itself becoming phosphorylated during the transport cycle. In this study, Na+ /K +-ATPase α-subunit c DNA was cloned from gill tissue of the swimming crab P ortunus trituberculatus by reverse-transcription polymerase chain reaction(RT-PCR) and rapid amplification of c DNA end methods. Analysis of the nucleotide sequence revealed that the c DNA had a full-length of 3 833 base pairs(bp), with an open reading frame of 3 120 bp, 5' untranslated region(UTR) of 317 bp, and 3' UTR of 396 bp. The sequence encoded a 1 039 amino acid protein with a predicted molecular weight of 115.57 k Da and with estimated p I of 5.21. It was predicted here to possess all expected features of Na+ /K +-ATPase members, including eight transmembrane domains, putative ATP-binding site, and phosphorylation site. Comparison of amino acid sequences showed that the P. trituberculatus α-subunit possessed an overall identity of 75%–99% to that of other organisms. Phylogenetic analysis revealed that this α-subunit was in the same category as those of crustaceans. Quantitative real-time RT-PCR analysis indicated that this α-subunit's transcript were most highly expressed in gill and lowest in muscle. RT-PCR analysis also revealed that α-subunit expression in crab gill decreased after 2 and 6 h, but increased after 12, 24, 48, and 72 h. In addition, α-subunit expression in hepatopancreas of crab decreased after 2–72 h. These facts indicated that the crab's Na+ /K +-ATPase α-subunit was potentially involved in the observed acute response to low salinity stress.展开更多
AIM: Functional characterization of ATP1A2 mutations that are related to familial or sporadic hemiplegic migraine(FHM2, SHM). METHODS: cRNA of human Na+/K+-ATPase α2- and β1-subunits were injected in Xenopus laevis ...AIM: Functional characterization of ATP1A2 mutations that are related to familial or sporadic hemiplegic migraine(FHM2, SHM). METHODS: cRNA of human Na+/K+-ATPase α2- and β1-subunits were injected in Xenopus laevis oocytes. FHM2 or SHM mutations of residues located in putative α/β interaction sites or in the α2-subunit's C-terminal region were investigated. Mutants were analyzed by the twoelectrode voltage-clamp(TEVC) technique on Xenopus oocytes. Stationary K+-induced Na+/K+ pump currents were measured, and the voltage dependence of apparent K+ affinity was investigated. Transient currents were recorded as ouabain-sensitive currents in Na+ buffers to analyze kinetics and voltage-dependent presteady state charge translocations. The expression of constructs was verified by preparation of plasma membrane and total membrane fractions of cRNA-injected oocytes. RESULTS: Compared to the wild-type enzyme, the mutants G900R and E902K showed no significant dif-ferences in the voltage dependence of K+-induced currents, and analysis of the transient currents indicated that the extracellular Na+ affinity was not affected. Mutant G855R showed no pump activity detectable by TEVC. Also for L994del and Y1009X, pump currents could not be recorded. Analysis of the plasma and total membrane fractions showed that the expressed proteins were not or only minimally targeted to the plasma membrane. Whereas the mutation K1003E had no impact on K+ interaction, D999H affected the voltage dependence of K+-induced currents. Furthermore, kinetics of the transient currents was altered compared to the wild-type enzyme, and the apparent affinity for extracellular Na+ was reduced. CONCLUSION: The investigated FHM2/SHM mutations influence protein function differently depending on the structural impact of the mutated residue.展开更多
文摘Aim: To explore the possible mechanisms of male infertility caused by antisperm antibody (AsAb). Methods: Thesoluble interleukin-2 receptor (sIL-2R) level in serum was analyzed by ELISA and Na^+ -K^+ -exchanging ATPase activi-ty in semen by phosphorus (Pi) assay. Results: The slL-2R level in serum was significantly higher and the Na^+ -K^+ -exchanging ATPase activity in semen significantly lower in AsAb positive infertile men when compared with thecontrols. Conclusion: The AsAb titer varies with the slL-2R level in serum. A decrease in Na^+ -K^+ -exchangingATPase activity in semen may play a role in male infertility caused by AsAb.
基金Supported by the National High Technology Research and Development Program of China(863 Program)(No.2012AA10A409)the National Natural Science Foundation of China(No.41306177)the Special Scientific Research Funds for Central Non-Profit Institutes,Yellow Sea Fisheries Research Institutes(No.20603022013027)
文摘A bstract Na + /K +-ATPases are membrane-associated enzymes responsible for the active transport of Na + and K + ions across cell membranes, generating chemical and electrical gradients. These enzymes' α-subunit provides catalytic function, binding and hydrolyzing ATP, and itself becoming phosphorylated during the transport cycle. In this study, Na+ /K +-ATPase α-subunit c DNA was cloned from gill tissue of the swimming crab P ortunus trituberculatus by reverse-transcription polymerase chain reaction(RT-PCR) and rapid amplification of c DNA end methods. Analysis of the nucleotide sequence revealed that the c DNA had a full-length of 3 833 base pairs(bp), with an open reading frame of 3 120 bp, 5' untranslated region(UTR) of 317 bp, and 3' UTR of 396 bp. The sequence encoded a 1 039 amino acid protein with a predicted molecular weight of 115.57 k Da and with estimated p I of 5.21. It was predicted here to possess all expected features of Na+ /K +-ATPase members, including eight transmembrane domains, putative ATP-binding site, and phosphorylation site. Comparison of amino acid sequences showed that the P. trituberculatus α-subunit possessed an overall identity of 75%–99% to that of other organisms. Phylogenetic analysis revealed that this α-subunit was in the same category as those of crustaceans. Quantitative real-time RT-PCR analysis indicated that this α-subunit's transcript were most highly expressed in gill and lowest in muscle. RT-PCR analysis also revealed that α-subunit expression in crab gill decreased after 2 and 6 h, but increased after 12, 24, 48, and 72 h. In addition, α-subunit expression in hepatopancreas of crab decreased after 2–72 h. These facts indicated that the crab's Na+ /K +-ATPase α-subunit was potentially involved in the observed acute response to low salinity stress.
基金Supported by German Research Foundation(Cluster of Excellence"Unifying Concepts in Catalysis")
文摘AIM: Functional characterization of ATP1A2 mutations that are related to familial or sporadic hemiplegic migraine(FHM2, SHM). METHODS: cRNA of human Na+/K+-ATPase α2- and β1-subunits were injected in Xenopus laevis oocytes. FHM2 or SHM mutations of residues located in putative α/β interaction sites or in the α2-subunit's C-terminal region were investigated. Mutants were analyzed by the twoelectrode voltage-clamp(TEVC) technique on Xenopus oocytes. Stationary K+-induced Na+/K+ pump currents were measured, and the voltage dependence of apparent K+ affinity was investigated. Transient currents were recorded as ouabain-sensitive currents in Na+ buffers to analyze kinetics and voltage-dependent presteady state charge translocations. The expression of constructs was verified by preparation of plasma membrane and total membrane fractions of cRNA-injected oocytes. RESULTS: Compared to the wild-type enzyme, the mutants G900R and E902K showed no significant dif-ferences in the voltage dependence of K+-induced currents, and analysis of the transient currents indicated that the extracellular Na+ affinity was not affected. Mutant G855R showed no pump activity detectable by TEVC. Also for L994del and Y1009X, pump currents could not be recorded. Analysis of the plasma and total membrane fractions showed that the expressed proteins were not or only minimally targeted to the plasma membrane. Whereas the mutation K1003E had no impact on K+ interaction, D999H affected the voltage dependence of K+-induced currents. Furthermore, kinetics of the transient currents was altered compared to the wild-type enzyme, and the apparent affinity for extracellular Na+ was reduced. CONCLUSION: The investigated FHM2/SHM mutations influence protein function differently depending on the structural impact of the mutated residue.
