title: An inducible expression system of the calcium-activated potassium channel 4 to study the differential impact on embryonic stem cells.
abstract: Rationale. The family of calcium-activated potassium channels consists of four members with varying biological functions and conductances. Besides membrane potential modulation, SK channels have been found to be involved in cardiac pacemaker cell development from ES cells and morphological shaping of neural stem cells. Objective. Distinct SK channel subtype expression in ES cells might elucidate their precise impact during cardiac development. We chose SK channel subtype 4 as a potential candidate influencing embryonic stem cell differentiation. Methods. We generated a doxycycline inducible mouse ES cell line via targeted homologous recombination of a cassette expressing a bicistronic construct encoding SK4 and a fluorophore from the murine HPRT locus. Conclusion. We characterized the mouse ES cell line iSK4-AcGFP. The cassette is readily expressed under the control of doxycycline, and the overexpression of SK4 led to an increase in cardiac and pacemaker cell differentiation thereby serving as a unique tool to characterize the cell biological variances due to specific SK channel overexpression.
authors.affiliation: Institute for Anatomy and Cell Biology, Ulm University, 89081 Ulm, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Liebau
authors.forename: Michael
authors.initials: M
authors.lastname: Tischendorf
authors.forename: Daniel
authors.initials: D
authors.lastname: Ansorge
authors.forename: Leonhard
authors.initials: L
authors.lastname: Linta
authors.forename: Marianne
authors.initials: M
authors.lastname: Stockmann
authors.forename: Clair
authors.initials: C
authors.lastname: Weidgang
authors.forename: Michelina
authors.initials: M
authors.lastname: Iacovino
authors.forename: Tobias
authors.initials: T
authors.lastname: Boeckers
authors.forename: Götz
authors.initials: G
authors.lastname: von Wichert
authors.forename: Michael
authors.initials: M
authors.lastname: Kyba
authors.forename: Alexander
authors.initials: A
authors.lastname: Kleger