Biomaterial Database

Characterization of the placental brush border membrane Na+/H+ exchanger: identification of thiol-dependent transitions in apparent molecular size. 1993

L Fliegel, and R S Haworth, and J R Dyck

Department of Biochemistry, Faculty of Medicine, University of Alberta, Edmonton, Canada.

We examined the protein and mRNA encoding the amiloride-sensitive Na+/H+ exchanger from human placenta. Reverse transcriptase PCR of human placental RNA and a human choriocarcinoma cell line showed that the message for the amiloride-sensitive Na+/H+ exchanger from human placenta. Reverse transcriptase PCR of human placental RNA and a human choriocarcinoma cell line showed that the message for the amiloride-sensitive Na+/H+ exchanger is present in the placenta and its derived cell line. Northern blot analysis showed only one species of Na+/H+ exchanger mRNA, of about 5 kb in size. To examine the Na+/H+ exchanger protein two different affinity-purified antibodies were produced against the C-terminal cytoplasmic region of the Na+/H+ exchanger. The antibodies both identified a 105 kDa protein in human placental brush border membrane vesicles. Under non-reducing conditions the amount of 105 kDa protein was greatly decreased, while a 205 kDa protein became apparent. This is probably a dimer of the 105 kDa protein. The monomer-to-dimer transition was dependent on the concentration of beta-mercaptoethanol. The results show that the amiloride-sensitive Na+/H+ exchanger is relatively abundant in human placenta and that it can exist as a larger 205 kDa protein linked by disulphide bonds.

UI	MeSH Term	Description	Entries
D008623	Mercaptoethanol	A water-soluble thiol derived from hydrogen sulfide and ethanol. It is used as a reducing agent for disulfide bonds and to protect sulfhydryl groups from oxidation.	2-ME,2-Mercaptoethanol,2 Mercaptoethanol
D008871	Microvilli	Minute projections of cell membranes which greatly increase the surface area of the cell.	Brush Border,Striated Border,Border, Brush,Border, Striated,Borders, Brush,Borders, Striated,Brush Borders,Microvillus,Striated Borders
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D010446	Peptide Fragments	Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.	Peptide Fragment,Fragment, Peptide,Fragments, Peptide
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D011257	Pregnancy Proteins	Proteins produced by organs of the mother or the PLACENTA during PREGNANCY. These proteins may be pregnancy-specific (present only during pregnancy) or pregnancy-associated (present during pregnancy or under other conditions such as hormone therapy or certain malignancies.)	Placental Proteins,Proteins, Placental,Proteins, Pregnancy
D002352	Carrier Proteins	Proteins that bind or transport specific substances in the blood, within the cell, or across cell membranes.	Binding Proteins,Carrier Protein,Transport Protein,Transport Proteins,Binding Protein,Protein, Carrier,Proteins, Carrier
D003001	Cloning, Molecular	The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.	Molecular Cloning
D004277	DNA, Single-Stranded	A single chain of deoxyribonucleotides that occurs in some bacteria and viruses. It usually exists as a covalently closed circle.	Single-Stranded DNA,DNA, Single Stranded,Single Stranded DNA