title: Transepithelial resistance in human bestrophin-1 stably transfected Madin-Darby canine kidney cells.
abstract: Bestrophin-1 (Best1) is a transmembrane protein, found in the basolateral plasma membrane of retinal pigmented epithelial cells. The exact structure and functions of Best1 protein are still unclear. The protein is thought to be a regulator of ion channels, or an ion channel itself: it was shown to be permeable for chloride, thiocyanate, bicarbonate, glutamate and γ-aminobutyric acid (GABA). Mutations in the gene for Best1 are leading to best vitelliform macular dystrophy (BVMD) and are found in several other types of maculopathy. In order to obtain additional information about Best1 protein, we determined cell polarization of a stably transfected Madin-Darby canine kidney cell line II (MDCK II) cell line, expressing human Best1. We measured the transepithelial resistance of transfected and non-transfected MDCK cells by voltmeter EVOM, over 10 days at 24 hour intervals. The first few days (first-fourth day) both cell lines showed the same or similar values ​​of transmembrane resistance. As expected, on the fifth day the non-transfected cells showed maximum value of epithelial resistance, corresponding to the forming of monolayer. The transfected cells showed maximum value of transepithelial resistance on the ninth day of their cultivation. Phalloidin staining of actin demonstrated the difference in actin arrangements between transfected and non-transfected cells due to Best1. As a consequence of actin rearrangement, Best1 strongly affects the transepithelial resistance of polarizing stably transfected MDCK cells. Our results suggest that Best1 protein has an effect on transepithelial resistance and actin rearrangements of polarized stably transfected MDCK cells.
authors.affiliation: Faculty of Biology, Sofia University "St. Kliment Ohridski" , Sofia , Bulgaria.
authors.forename: Kirilka
authors.initials: K
authors.lastname: Mladenova
authors.affiliation: Faculty of Biology, Sofia University "St. Kliment Ohridski" , Sofia , Bulgaria.
authors.forename: Svetla
authors.initials: S
authors.lastname: Petrova
authors.affiliation: Faculty of Biology, Sofia University "St. Kliment Ohridski" , Sofia , Bulgaria.
authors.forename: Veselina
authors.initials: V
authors.lastname: Moskova-Doumanova
authors.affiliation: Faculty of Biology, Sofia University "St. Kliment Ohridski" , Sofia , Bulgaria.
authors.forename: Tanya
authors.initials: T
authors.lastname: Topouzova-Hristova
authors.affiliation: Institute of Microbiology, Bulgarian Academy of Science , Sofia , Bulgaria.
authors.forename: Stoyanka
authors.initials: S
authors.lastname: Stoitsova
authors.affiliation: Faculty of Biology, Sofia University "St. Kliment Ohridski" , Sofia , Bulgaria.
authors.forename: Irena
authors.initials: I
authors.lastname: Tabashka
authors.affiliation: Institute of Ophthalmology, UCL , London , UK.
authors.forename: Christina
authors.initials: C
authors.lastname: Chakarova
authors.affiliation: Faculty of Biology, Sofia University "St. Kliment Ohridski" , Sofia , Bulgaria.
authors.forename: Zdravko
authors.initials: Z
authors.lastname: Lalchev
authors.affiliation: Faculty of Biology, Sofia University "St. Kliment Ohridski" , Sofia , Bulgaria.
authors.forename: Jordan
authors.initials: J
authors.lastname: Doumanov
keywords: BVMD; MDCK cells; actin; hBest1