Skip to main content
. 2015 Mar 24;27(4):1140–1161. doi: 10.1105/tpc.114.135400

Figure 2.

Figure 2.

RIC1 Acts on Apical Actin Filaments in Pollen Tubes.

All data are presented as means ± se. *P < 0.05, by Student’s t test.

(A) Ws-2 and ric1-1 pollen tubes were incubated on germination medium containing different concentrations of oryzalin. The average lengths of treated pollen tubes relative to untreated controls at 3 h after germination were calculated. Untreated controls were normalized to 100% for Ws-2 and ric1-1 pollen. Oryzalin had little effect on pollen tube growth. CK, untreated control.

(B) Ws-2, ric1-1, Col-0, and OX 9 pollen tubes were incubated on germination medium containing 1 nM LatB. The average lengths of treated pollen tubes relative to untreated controls at 3 h after germination were calculated. Untreated controls were normalized to 100% for pollen from each line. ric1-1 pollen tubes were more resistant to LatB than wild-type (Ws-2) tubes, whereas there was no significant difference between OX 9 and Col-0 pollen tubes.

(C) Schematic showing how the apical dome zone in the pollen tube was defined. A semielliptical region circumscribed by the dotted line at the tip was selected for the apical F-actin analyses shown in (D).

(D) Time-lapse images from Supplemental Movie 1 (Col-0), Supplemental Movie 2 [ric1-1 (Col-0)], and Supplemental Movie 3 (RIC1 OX 9) showing F-actin dynamics in growing pollen tubes. Bar = 5 μm.

(E) Oscillations of fine F-actin in the apical dome were quantified by measuring fluorescence intensity in representative growing Col-0, ric1-1 (Col-0), and RIC1 OX 9 pollen tubes shown in (D). Compared with Col-0, apical F-actin structures in ric1-1 pollen tubes were more abundant, while there were fewer apical F-actin structures in RIC1 OX 9 pollen tubes. a.u., arbitrary units.

(F) Average maximum and minimum fluorescence intensities of F-actin in the apical dome of Col-0 (n = 20), ric1-1 (Col-0) (n = 20), and RIC1 OX 9 (n = 10) pollen tubes. Compared with Col-0, apical F-actin structures in ric1-1 pollen tubes were more abundant with greater oscillatory amplitude, while there were fewer apical F-actin structures with decreased oscillatory amplitude in RIC1 OX 9 pollen tubes.