Interaction between regions of 4.1R and eIF3-p44 in the yeast 2-hybrid system.

The eIF3-p44 clone (p44-1) was first isolated by a yeast 2-hybrid screen from a human lymphocyte cDNA library using the 22/24-kd domain of 4.1R (4.1R-22) as bait. (A) Schematic diagram of the various portions of 4.1R that interact with eIF3-p44 in a yeast 2-hybrid screen. The constructs containing various portions of 4.1R fused to the DNA binding domain of Gal4 (Gal4-BD) were cotransformed with an eIF3-p44/pACT2 clone (p44-1) that expressed eIF3-p44 (residues 54-321) fused to the activation domain of Gal4 (Gal4-AD). (B) Schematic diagram of various portions of eIF3-p44 that interact with 4.1R. A series of eIF3-p44 deletion mutants, fused to Gal-AD in the pACT2 vector, were cotransformed with 4.1R-22/pAS2-1 in Y187 cells. +, expression of the lacZ reporter gene using the colony-lift assay; −, nonexpression of the reporter gene. Right-hand column represents results of the liquid assay for β-galactosidase activity.