The aim of the present work was to study the binding of [I-125]-BLGA (beta-lactoglobulin variant A) to the plasma membrane fraction of hybrid cells. This binding increased as a function of time with on-rate and off-rate constant at 4.47 +/- 0.18 x 10(6) M-1 min(-1) and 0.17 +/- 0.07 min(-1), respectively (n = 3). The saturation study showed a single binding site type corresponding to a K-d at 8.26 +/- 2.98 nM and 14.02 +/- 2.61 x 10(12) sites per mg of the plasma membrane protein (n = 3). Competitive of binding BLGA was observed with BLGA, complexed with retinol and also with RBP (retinol-binding protein). Gel filtration of [I-125]-BLGA incubated with Triton X-100 solubilized membrane showed the formation of a ligand-receptor complex. Cross-linking of the tracer to plasma membrane showed a complex with a M-r at 69 kDa, suggesting a receptor M-r of 51 kDa, as seen by autoradiography of SDS-PAGE.
Plasma membrane receptor for beta-lactoglobulin and retinol-binding protein in murine hybridomas
PELOSI, PAOLO;
1998-01-01
Abstract
The aim of the present work was to study the binding of [I-125]-BLGA (beta-lactoglobulin variant A) to the plasma membrane fraction of hybrid cells. This binding increased as a function of time with on-rate and off-rate constant at 4.47 +/- 0.18 x 10(6) M-1 min(-1) and 0.17 +/- 0.07 min(-1), respectively (n = 3). The saturation study showed a single binding site type corresponding to a K-d at 8.26 +/- 2.98 nM and 14.02 +/- 2.61 x 10(12) sites per mg of the plasma membrane protein (n = 3). Competitive of binding BLGA was observed with BLGA, complexed with retinol and also with RBP (retinol-binding protein). Gel filtration of [I-125]-BLGA incubated with Triton X-100 solubilized membrane showed the formation of a ligand-receptor complex. Cross-linking of the tracer to plasma membrane showed a complex with a M-r at 69 kDa, suggesting a receptor M-r of 51 kDa, as seen by autoradiography of SDS-PAGE.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
