Many studies of ion channels expressed by neural tissues have focused on channels gated by ligands or voltage. In this mini review, another relatively new class of ion channels will be discussed – those known more for their constitutive activity than for gating properties. Prior to 1995, K+ channel subunits had been isolated with one pore domain that encoded voltage-gated or inward rectifier channels. However, that year a yeast K+ channel subunit was identified that contained two pore domains in tandem within its primary amino acid sequence7. When expressed, functional channels were formed whose activation was coupled to the equilibrium potential for K+ and passed large amounts of outward current at depolarized potentials. Accordingly, this channel was named TOK1 (two P domain outward rectifier K+ channel). TOK1 is the only K+
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Issue No. 13
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Endothelin Receptors
In 1988, a 21-amino acid endothelium-derived bioactive peptide was cloned and named endothelin (ET)1. Later, two other isoforms differing from …
Continue readingNovel Neurotrophic Factors
Heparin – binding growth factors have been implicated in central nervous system development, regeneration and pathology. Typical members of this family of secreted cytokines are basic Fibroblast Growth Factor (human FGF-basic), Midkine and Pleiotrophin.
human Midkine, a 13 kDa heparin-binding growth factor with 50% sequence identity to Pleiotrophin is the product of a retinoic acid responsive gene and is a developmental regulated, highly conserved, neurotrophic factor2 which induces neurite extension3 ,4 and neuronal survival5. human Pleiotrophin, an 18 kDa, heparin–binding growth – associated molecule (HB-GAM,HBGF-8)6 is also a developmentally regulated neurotrophin which promotes neurite out growth7, 8, axonal guidance9 and
Continue readingERG K+ Channels
The first member of the Eag family was cloned in Drosophila melanogaster in 19915, 6. The mutants in its gene, …
Continue readingThe Molecular Diversity of TRPC Channels and Related Proteins
The cytosolic Ca2+ serves an intracellular mediator for many extracellular signals. The receptors coupling via heterotrimeric G proteins to different …
Continue readingCell Death Modulators for in vitro Apoptosis Models
Until the beginning of 1980s, nerve cell necrosis was thought to responsible for nerve cell death in human brain, stroke …
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