Purification and subunit structure of a putative K+-channel protein identified by its binding properties for dendrotoxin I.

Abstract

The binding protein for the K+-channel toxin dendrotoxin I was purified from a detergent extract ofrat brain membranes. The purification procedure utilized chromatography on DEAE-Trisacryl, affinity chromatography on a dendrotoxin

Cloning of a human cDNA expressing a high voltage‐activating. Tea‐sensitive, type‐a K+ channel which maps to chromosome 1 band p21

“…In addition, Sh proteins may undergo posttranslational modifications such as glycosylation and phosphorylation, which could change the properties of Sh channels . Channels composed of Sh subunits can apparently also interact with other not yet identified subunits, and this may also change the functional properties of the final product (Rehm et al, 1989a,b;Rehm and Lazdunski 1988;Rudy et al, 1988Rudy et al, , 1991. Factors such as those listed here are likely to contribute to the functional properties of native channels containing HKShIIIC proteins.…”

Characterization of Ca2+‐activated 86Rb+ fluxes in rat C6 glioma cells: a system for identifying novel IKCa‐channel toxins

“…Toxins play an important role in the molecular characterization of potassium channels (Rehm & Lazdunski, 1988;Scott et al, 1990;Garcia-Calvo et al, 1991), which is complementary to cDNA cloning approaches. The discovery and characterization of novel toxins which selectively modulate different channel subtypes will no doubt continue to contribute to our understanding of structural and functional relationships between different members of this large family of ion channel proteins.…”

Use of Venom Peptides to Probe Ion Channel Structure and Function

“…These peptides comprise 57-60 aa and three disulfide bonds that stabilize a "Kunitz-type toxin" fold. Initially, the high affinity binding of dendrotoxins was exploited to isolate a K ϩ channel protein (24). Later, structure-activity studies of ␣-and ␦-dendrotoxins revealed the importance of the functional dyad, and several models of the interaction of dendrotoxins with K ϩ channels have been proposed (25,26).…”