Phosphatidylserine (PtdSer) in Chinese hamster ovary (CHO) cells is synthesized through the action of PtdSer synthase (PSS) I and II, which catalyzes the exchange of L-serine with the base moiety of phosphatidylcholine and phosphatidylethanolamine, respectively. The PtdSer synthesis in a CHO cell mutant, PSA-3, which lacks PSS I but has normal PSS II activity, was almost completely inhibited by...

Rennie, K. J., J. F. Ashmore, and M. J. Correia. Evidence for an Na1-K1-Cl2 cotransporter in mammalian type I vestibular hair cells. Am. J. Physiol. 273 (Cell Physiol. 42): C1972–C1980, 1997.—In amniotes, there are two types of hair cells, designated I and II, that differ in their morphology, innervation pattern, and ionic membrane properties. Type I cells are unique among hair cells in that th...

Abstract In this paper, we introduce the notion of a connected sum K1 #Z K2 of simplicial complexes K1 and K2, as well as define a strong connected sum. Geometrically, the connected sum is motivated by Lerman’s symplectic cut applied to a toric orbifold, and algebraically, it is motivated by the connected sum of rings introduced by Ananthnarayan–Avramov–Moore [1]. We show that the Stanley–Reisn...

Tetraethylammonium (TEA1) is widely used for reversible blockade of K channels in many preparations. We noticed that intracellular perfusion of voltage-clamped squid giant axons with a solution containing K1 and TEA1 irreversibly decreased the potassium current when there was no K1 outside. Five minutes of perfusion with 20 mM TEA1, followed by removal of TEA1, reduced potassium current to <5% ...

The purpose of this study was to validate a method for measuring vitamin K isomers in rat tissues by liquid chromatography (LC) with fluorescence detection after simple solvent extraction. This method uses separation on a C30 column, followed by zinc reduction and fluorescence measurement (243 nm, excitation; 430 nm, emission) to detect and quantitate vitamin K isomers. We were able to separate...

Keratins K1 and K10 represent the major differentiation products of the maturing epidermal keratinocytes. Primary epidermal cell cultures from newborn K1 transgenic mice containing a 12-kilobase human K1 genomic fragment were established in order to examine the expression of both human and mouse K1 in the presence of known modulators of epidermal differentiation. Elevated levels of Ca2+ in the ...

SII-K1 is a member of the transcription elongation factor S-II family. In the mouse, SII-K1 is expressed exclusively in the liver, kidney, heart, and skeletal muscle. Here, we report that deletion of the SII-K1 gene in mice resulted in the downregulation of the synaptotagmin-like 1 (Sytl 1) gene in liver and of the coiled-coil domain-containing 21 (Ccdc21) gene in liver and kidney. Moreover, th...