Table II. Analysis of SMN and extranucleolar foci in MEF cell lines.

MEF	Genotype	Extranucleolar focia,b	SMN focia	SMN foci containing Nopp
			%	%
26	+/+	60–80c (1.7/cell)d	20–30 (1.4/cell)d	90 (212 of 237)
42	−/−	10–30 (∼1/cell)d	15–25 (1.5/cell)d	0 (0 of 368)
43	−/−	10–30 (∼1/cell)d	<10 (1.5/cell)d	0 (0 of 268)

^aFraction of cells with one or more foci; ranges reflect variability between experiments.

^bFoci scored with Fb or Nopp in the presence of NOH61 to exclude small nucleoli.

^cSimilar results were obtained when cells were scored with anticoilin antibodies.

^dScored for cells with one or more foci.