TABLE 1.

Quantification of adaptin binding to fusion proteins

Fusion proteina	α-Adaptinb		γ-Adaptin
	Amt boundc	% Differenced	Amt bound	% Difference
C terminal	657 ± 33	NA	618 ± 54	NA
Y72A	140 ± 8	−79	222 ± 19	−64
Y79A	1,009 ± 97	+53	373 ± 23	−40

^aPeripheral membrane proteins were incubated with 100 μg of fusion protein attached to glutathione beads. The fusion proteins tested had either wild-type RIDα Ile63-Leu91 sequences or Ile63-Leu91 sequences with Y72A or Y79A substitutions.

^bBound proteins were immunoblotted with adaptin-specific antibodies followed by a ¹²⁵I-labeled secondary antibody, and blots were exposed to a phosphor screen.

^cVolume integration of pixel values in a defined area with background subtracted. Pixel values are arbitrary units that are proportional to the amount of radiation stored and re-emitted from the phosphor screen. Values in the table are the means from three independent determinations for each band ± standard errors of the means and have been multiplied by 10⁻³. Similar results were obtained in two independent determinations.

^dPercent difference relative to the amount of protein bound to C-terminal fusion protein, which is set to 100%.