Cell calcium signalling induced by endogenous lectin carbohydrate interaction in the Jurkat T cell line |
| |
Authors: | Hermann Walzel Jun Hirabayashi Ken-Ichi Kasai Josef Brock Peter Neels |
| |
Institution: | (1) Institute of Medical Biochemistry, University of Rostock, Schillingallee 70, D-18057 Rostock, Germany;(2) Department of Biological Chemistry, Faculty of Pharmaceutical Sciences, Teikyo University, 199-01 Sagamiko, Kanagawa, Japan |
| |
Abstract: | The effects of the -galactoside-binding lectin from human placenta (HPL14) on intracellular calcium concentration (Ca2+]i) were examined in the human Jurkat T cell line. The lectin induces a concentration dependent increase in Ca2+]i. This calcium signalling effect is clearly mediated through complementary cell surface galactoglycoconjugates because it can be blocked by -galactosides. The observed Ca2+-response involves both the release of calcium from intracellular stores and a calcium influx from the extracellular space. It is sustained in the presence of 1 mM extracellular calcium whereas it becomes transient when the influx of extracellular calcium was blocked by calcium chelation to EGTA. Voltage-sensitive calcium channel blockers like verapamil and prenylamine were without effect on the action of HPL14. Protection of the sugar binding activity of HPL14 in the absence of a thiol-reducing reagent by carboxamidomethylation (CM-HPL14) or by substitution Cys2 with serine (C2S) results in lectin proteins with considerably decreased calcium signalling efficiency. The recombinant lectin (Rec H) and the mutant protein obtained by substitution of highly conservative Trp68 with tyrosine (W68Y) induce lower levels of Ca2+]i compared to wild type lectin.Abbreviation Ca2+]i
concentration of intracytoplasmic free calcium
- CM
carboxamidomethylation
- CRD
earbohydrate recognition domain
- C2S
mutant lectin protein in which Cys2 was replaced by serine
- EGTA
ethyleneglycol-bis(2-aminoethylether)-N,N,N
-
N -tetraacetic acid
HEPES,N-(2-hydroxyethyl)piperazine-N -2-ethanesulfonic acid
- HPL14
human -galactoside-binding placental lectin
- Rec H
recombinant human 14 kDa lectin
- W68Y
mutant lectin protein in which Trp68 was substituted to tyrosine |
| |
Keywords: | -galactoside-binding lectin" target="_blank">gif" alt="beta" align="MIDDLE" BORDER="0">-galactoside-binding lectin cell calcium signalling Jurkat T cells |
本文献已被 SpringerLink 等数据库收录! |
|