Fig. 1. Effect of Hub expression on immunolocalization by confocal microscopy of
clathrin light chain and proinsulin. Rat islet cells were infected with
Adeno-Hub/EGFP (a recombinant adenovirus expressing both the Hub peptide and
EGFP such that the latter is a marker for Hub expression) or with Adeno-EGFP
(only expressing EGFP) as indicated. The left-hand images show direct EGFP
fluorescence. Right-hand images show staining for (A) clathrin light chain;
(B) proinsulin. Control cells infected with Adeno-EGFP show a strong
perinuclear and punctate staining for clathrin light chain regardless of the
level of EGFP expression (A: lower). Expression of Hub leads to the
disappearance of the perinuclear and punctate staining pattern for clathrin
light chain in those cells with the highest level of expression of EGFP (and
thus Hub — see representative cell marked by arrow in A: upper), whereas
cells in the same cluster but expressing low or nondetectable levels of EGFP
(and thus Hub) present normal clathrin light chain staining (see
representative cell marked by arrowhead in A: upper). Proinsulin
immunostaining (B) was unaffected by expression of Hub, with all cells
presenting the same staining pattern regardless of the level of EGFP
expression. Bar, 10 µm.
