Learn More
Structure-function relationships of the sodium channel expressed in Xenopus oocytes have been investigated by the combined use of site-directed mutagenesis and patch-clamp recording. This study provides evidence that the positive charges in segment S4 are involved in the voltage-sensing mechanism for activation of the channel and that the region between(More)
The results of previous in vitro experiments indicate that a glycosylphosphatidylinositol (GPI)-anchored protein may play an important role in the guidance of temporal retinal axons during the formation of the topographically ordered retinotectal projection. We have purified and cloned a GPI-anchored, 25 kDa glycoprotein that is a good candidate for a(More)
The levels of the mRNAs encoding sodium channels I, II and III in various regions of the developing rat central nervous system (from embryonal day 10 to postnatal day 90) have been examined by blot hybridization analysis with specific probes. The three sodium channel mRNAs exhibit different temporal and regional expression patterns. The expression of sodium(More)
6B4 proteoglycan/phosphacan is one of the major phosphate-buffered saline-soluble chondroitin sulfate proteoglycans of the brain. Recently, this molecule has been demonstrated to be an extracellular variant of the proteoglycan-type protein tyrosine phosphatase, PTPzeta (RPTPbeta). The influence of the 6B4 proteoglycan, adsorbed onto the substratum, on cell(More)
The direction of image motion is coded by direction-selective (DS) ganglion cells in the retina. Particularly, the ON DS ganglion cells project their axons specifically to terminal nuclei of the accessory optic system (AOS) responsible for optokinetic reflex (OKR). We recently generated a knock-in mouse in which SPIG1 (SPARC-related protein containing(More)
Na(v)2/NaG is a putative sodium channel, whose physiological role has long been an enigma. We generated Na(v)2 gene-deficient mice by inserting the lacZ gene. Analysis of the targeted mice allowed us to identify Na(v)2-producing cells by examining the lacZ expression. Besides in the lung, heart, dorsal root ganglia, and Schwann cells in the peripheral(More)
Topographical maps of neuronal connectivity occur in various brain regions. In the visual system of birds, retinal ganglion-cell axons from the anterior retina connect to a posterior part of the optic tectum, and posterior retinal axons connect to the anterior part, thereby establishing a point-to-point projection map. The chemoaffinity theory predicts that(More)
In Shaker-group potassium channels the presence of a tyrosine residue, just downstream of the pore signature sequence GYG, determines sensitivity to tetraethylammonium (TEA). The KCNQ family of channels has a variety of amino acid residues in the equivalent position. We studied the effect of TEA on currents generated by KCNQ homomers and heteromers(More)
Sodium (Na) homeostasis is crucial for life, and Na levels in body fluids are constantly monitored in the brain. The subfornical organ (SFO) is the center of the sensing responsible for the control of salt-intake behavior, where Na(x) channels are expressed in specific glial cells as the Na-level sensor. Here, we show direct interaction between Na(x)(More)
Pleiotrophin/heparin-binding growth-associated molecule (HB-GAM) is a specific ligand of protein tyrosine phosphatase zeta (PTPzeta)/receptor-like protein tyrosine phosphatase beta (RPTPbeta) expressed in the brain as a chondroitin sulfate proteoglycan. Pleiotrophin and PTPzeta isoforms are localized along the radial glial fibers, a scaffold for neuronal(More)