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Fig. 4. SNAP-23 was redistributed to the ER in cells expressing syntaxin 1. HeLa
cells transfected with syntaxin 1 or co-transfected with syntaxin 1 and nSec1
as indicated were fixed and double stained for syntaxin 1 and endogenous
SNAP-23 (A) or the plasma membrane marker Na+/K+ ATPase
(B). Note the colocalization of SNAP-23 and ectopic syntaxin 1 (arrowhead) and
the absence of SNAP-23 from the plasma membrane in cells expressing syntaxin 1
alone and the plasma membrane staining of SNAP-23 in non-transfected cells or
in cells co-transfected with syntaxin 1 plus nSec1 (arrows). By contrast,
endogenous Na+/K+ ATPase is not relocalized from the
plasma membrane in syntaxin-1-expressing cells. Bar, 7 µm.