Identification of the glucose transport protein of the microvillous membrane of human placenta by photoaffinity labelling
Johnson, L.W.; Smith, C.H.
Biochemical and Biophysical Research Communications 109(2): 408-413
1982
ISSN/ISBN: 0006-291X PMID: 6891216 Document Number: 183502
The initial step in transfer of glucose from mother to fetus is facilitated diffusion transport across the microvillous membrane of the placental syncytium. 3H-Cytochalasin B was used as a photoaffinity label to identify the transport protein involved. Two binding proteins were present, one of which is apparently the glucose transport protein and one of which is actin. The 2 were identified by competition labeling with D-glucose, and cytochalasin E. They were separated by selective extraction with dimethyl maleic anhydride. The glucose transport protein is apparently a single molecular species of 52,000 MW.