Deletion of C-terminal 12 amino acids of GLUT1 protein does not abolish the transport activity.
We engineered the GLUT1 cDNA to delete C-terminal 12 amino acids of encoded GLUT1 protein. This mutated GLUT1 protein expressed in CHO cells by transfection of its cDNA was demonstrated to reside on the plasma membrane by cell surface labeling technique, and retain the transport activity, similar to that of the wild-type GLUT1. In addition, metabolic labeling of the intact cells with 35S indicated that the half-life of the mutated GLUT1 was not significantly different from that of the wild-type GLUT1. These results suggest that C-terminal 12 amino acids of GLUT1 are not important for the transport activity and the stability of the protein. Taken together with our previous results on the mutant without C-terminal 37 amino acids, the amino acids between the 37th and the 13th from the C-terminus appear to be essential for the transport activity.
Lin
J L
JL
Third Department of Internal Medicine, Faculty of Medicine, University of Tokyo, Japan.
Asano
T
T
Katagiri
H
H
Tsukuda
K
K
Ishihara
H
H
Inukai
K
K
Yazaki
Y
Y
Oka
Y
Y
D000818:Animals; D001483:Base Sequence; D001894:Borohydrides / Q000378:metabolism; D016466:CHO Cells; D002462:Cell Membrane / Q000378:metabolism; D002872:Chromosome Deletion; D006224:Cricetinae; D004247:DNA / Q000235:genetics; D003847:Deoxyglucose / Q000378:metabolism*; D005692:Galactose Oxidase / Q000378:metabolism; D007700:Kinetics; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009004:Monosaccharide Transport Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D016297:Mutagenesis, Site-Directed; D009838:Oligodeoxyribonucleotides; D011817:Rabbits; D014162:Transfection
D001894:Borohydrides; D009004:Monosaccharide Transport Proteins; D009838:Oligodeoxyribonucleotides; C025364:sodium borohydride; D004247:DNA; D003847:Deoxyglucose; D005692:Galactose Oxidase