Figure 3.

CTL1 Localizes to Endomembranes That Move along Actin Filaments.

CLSM images of 4-d-old etiolated CTL1:GFP hypocotyl epidermal cells.

(A) CTL1 localizes to Golgi bodies (yellow circles) and unknown vesicles (yellow arrowheads; CTL1v).

(B) to (F) CTL1vs show different migratory patterns; the vesicles associate and dissociate with Golgi bodies (B), the vesicles’ linear movements are interrupted by short periods of fixed positions (C), sometimes the vesicles are immobile (D), they bifurcate (E), or two independent vesicles move together in close vicinity of each other (F). Typical motility patterns of CTL1vs are shown in Supplemental Movie 2 online.

(C) to (E) Kymographs from CTL1v over the indicated time in seconds (green line = migration path).

(G) and (H) CTL1v movement depends on an intact actin cytoskeleton.

(G) CLSM images of a cell from a seedling expressing CTL1:GFP after 16-h treatment with 20 μM oryzalin or 1 mM LatB for 3 h, which are microtubule and actin disruptors, respectively. CTLvs are indicated by yellow arrowheads. Control treatment is included for comparison. Kymographs from CTL1v over the indicated time in seconds (green line = migration path). Typical motility patterns of CTL1 are shown in Supplemental Movie 3 online.

(H) Seedlings expressing CTL1:GFP and mCherryRFP:FABD were imaged under standard (water) conditions. CTL1v moving over actin filaments is indicated by a white arrowhead. Typical movement of CTL1v along the actin cytoskeleton is shown in Supplemental Movie 4 online.

Bars = 5 μm in (A), (G), and (H), 2 μm in (B) to (F), and 1 μm in kymographs in (C) to (E).