TABLE 1.

Chromosome binding activity of EBNA-1 derivatives following chromosome spreading and in living cells

Mutant	Amino acids	Binding to chromosome spreadingsa	Binding in mitotic living cellsb	% Positive mitotic living cellsc
EBNA-1	8–641	+	++	100
M1	378–641	−	−	0
M2	8–487	+	++	100
M3	57–432	+	++	100
M4	8–410Δ95–314	+	++	100
M5	8–89	+	+	100
M6	8–67	−	++	100
M7	8–54	−	+	<10
M8	57–67	−	−	0
M9	56–89	+	+	100
M10	70–89	+	++	100
M11	72–84	+	+	100
M12	57–641	+	++	100
M13	8–641Δ68–90	−	++	100
M14	91–641	−	+	<10
M15	378–606	−	−	0
M16	91–456	−	+	<10
M17	91–410	−	+	<10
M18	328–456	−	++	100
M19	328–410	−	++	100
M20	328–393	−	++	100
M21	328–365	−	++	100
M22	378–456	−	−	0
M23	378–410	−	−	0
M24	370–393	−	−	0

^aBinding was observed by fluorescence microscopy in the presence of PBS following centrifugation of transfected mitotic cells onto microscope slides. 

^bTransfected HeLa cells were grown on coverslips and observed by fluorescence microscopy at a low light level. When binding was observed, the protein was localized mainly on the chromosomes (++) or localized both on the chromosomes and in the nucleoplasm (+). 

^cFor some mutants, binding to metaphase chromosomes could be observed in only a fraction of transfected mitotic cells.