Site-specific mutagenesis of the human interleukin-1 beta gene: the role of arginine residue at the N-terminal region.
Using the expression system for site-specific mutagenesis in Escherichia coli, we have made deletion mutants at the N-terminal or C-terminal region of human interleukin-1 beta (IL-1 beta) consisting of 153 amino acids. The truncated mutants showed that at least 147 amino acids (numbers 4-150) in IL-1 beta are necessary for the exertion of biological activity. When we changed the arginine at the 4th position (Arg4) in IL-1 beta to other specific amino acids, there was a marked difference in the relative extent of biological and receptor binding activities among the mutants. The order of the mutants was Arg4 = Lys4 greater than Gln4 greater than Gly4 = des-Arg4 greater than Asp4. Our results demonstrate that the arginine residue at the 4th position in IL-1 beta is important, but not essential, for IL-1 beta to exhibit its biological and receptor binding activities, and the positive charge at this site plays a key role for IL-1 beta to exert the activities.
Kamogashira
T
T
Laboratories of Cellular Technology, Otsuka Pharmaceutical Co., Ltd., Tokushima.
Sakaguchi
M
M
Ohmoto
Y
Y
Mizuno
K
K
Shimizu
R
R
Nagamura
K
K
Nakai
S
S
Masui
Y
Y
Hirai
Y
Y
D001120:Arginine / Q000502:physiology*; D001665:Binding Sites; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D006801:Humans; D015151:Immunoblotting; D007375:Interleukin-1 / Q000235:genetics* / Q000494:pharmacology; D008545:Melanoma; D009154:Mutation; D014407:Tumor Cells, Cultured / Q000187:drug effects
D007375:Interleukin-1; D001120:Arginine