Btn1p regulates Golgi number and positioning. Absence of btn1
causes a reduction in the number of Gms1p-stained Golgi compartments. (A)
Confocal images of wild-type (wt) btn1Δ cells expressing
Gms1p-CFP showing reduced numbers of Golgi and positioning defects (end panel
shows a single typical cell). (B) Bar chart of numbers of Golgi in wild-type
(wt), btn1Δ cells and wild-type cells overexpressing Btn1p
(n>200 Golgi across single cross-sections in three independent
experiments); wild-type cells, 7.1±2.2; btn1Δ cells,
4.2±1.4; cells overexpressing Btn1p, 5.9±2.59;
***P<0.001. (C) Absence of btn1 or ectopic
expression of Btn1p alters the distribution of Golgi compartments. Bar chart
of positions of Gms1p-stained Golgi compartments in wild-type (wt),
btn1Δ cells and cells overexpressing Btn1p with respect to
their distance from the nucleus. The cartoon in A illustrates the positions of
regions counted (n>200 Golgi over three experiments). Scale bars:
10 μm.