TABLE 1.

Efficiency of fusion protein shuttling in COS-1/NIH 3T3 heterokaryons

Fusion protein	No. of heterokaryonsa	% Shuttledb
GFP 1-742	86	100
NLS-βgal	205	20.5
NLS-Rev βgal	107	95
NLS-485-495 βgal	79	82.3
1-319 βgal	51	96
1-131 βgal	51	96
1-66 βgal	49	8.5
NLS-67-131 βgal	125	93.7
NLS-67-123 βgal	177	95
NLS-67-95 βgal	168	21.4
NLS-95-123 βgal	98	96
GFP ΔNES2	71	94.4

^aNumber of heterokaryons counted for each fusion protein.

^bPercentage of heterokaryons containing fusion protein in the nuclei of both COS-1 cells and NIH-3T3 cells.