Differentiation of mouse embryonic stem cells into a defined neuronal lineage

Although it has long been known that cultured embryonic stem cells can generate neurons, the lineage relationships with their immediate precursors remain unclear. We report here that selection of highly proliferative stem cells followed by treatment with retinoic acid generated essentially pure precursors that markers identified as Pax-6-positive radial glial cells. As they do in vivo, these cells went on to generate neurons with remarkably uniform biochemical and electrophysiological characteristics

Specific Anion and Cation Binding to Lipid Membranes Investigated on a Solid Supported Membrane

Ion binding to a lipid membrane is studied by application of a rapid soln. exchange on a solid supported membrane. The resulting charge displacement is analyzed in terms of the affinity of the applied ions to the lipid surface. The authors find that chaotropic anions and kosmotropic cations are attracted to the membrane independent of the membrane compn. In particular, the same behavior is found for lipid headgroups bearing no charge, like monoolein. This general trend is modulated by electrostatic interaction of the ions with the lipid headgroup charge. These results cannot be explained with the current models of specific ion interactions