Article Figures & Data
Figures
- Figure 1.
Differential activities of PINs in the Arabidopsis root hair. A, Two distinctive PIN groups with different central hydrophilic loop sizes. Topology of PIN proteins was predicted by four different programs as described in Supplemental Figure S1. Numbers above indicate the number of transmembrane helices for each N- and C-terminal region, and numbers below indicate the number of amino acid residues of the central hydrophilic domain. B, Representative root images of control (Cont; Columbia-0) and root-hair-specific PIN-overexpressing (PINox; ProE7:PIN-GFP or ProE7:PIN [−]) plants. Bar = 100 μm for all. C, Root hair lengths of control and PINox plants. Six to 12 independent transgenic lines (average = 8.3), and 42 to 243 roots (average = 86.8) and 336 to 2,187 root hairs (average = 727.8) per construct, were observed for the estimation of root hair length. Data represent means ± se. The root hair lengths of PIN5ox lines were significantly longer than those of the control (P = 0.016 for PIN5ox; P < 0.0001 for PIN5-GFP1ox and PIN5-GFP2ox).
- Figure 2.
Effect of root hair cell-specific expression of PINs on elongation of roots and root hair epidermal cells. A, Four-day-old seedlings of control (Cont; Columbia-0) and PINox (ProE7:PIN-GFP) lines. Bar = 0.5 cm. B, Root hair epidermal cell length in PINox lines. The length between two consecutive root hairs in the same hair cell file was measured as the root hair cell length for control and PINox lines. Five independent transgenic lines for each transformant were analyzed. Data represent means ± se (n = 350–500). [See online article for color version of this figure.]
- Figure 3.
Subcellular localization of PIN-GFP proteins in the Arabidopsis root hair cell. A and B, Root hair specifically expressed PIN-GFP (ProE7:PIN-GFP; PIN5 = ProE7:PIN5-GFP1) fusion proteins were visualized by confocal microscopy. Root hair cells were visualized by only GFP signal (A) or by both GFP and FM4-64 dye signals (B). GFP and FM4-64 signals at the plasma membrane were merged for PIN3 and PIN8, whereas they were not for PIN5 (B). Bars = 10 μm for A and 5 μm for B.
- Figure 4.
Subcellular localization of short-looped PINs in tobacco cells. A and B, PIN-GFP (ProTA:PIN-GFP; PIN5 = ProTA:PIN5-GFP1) fusion proteins were visualized by confocal microscopy. Expression of the fusion proteins was induced by 0.01 mm Dex for 24 h. Cells were visualized by GFP and FM4-64 dye signals. GFP and FM4-64 signals at the plasma membrane were merged for PIN3 and PIN8, whereas they were not for PIN5. Bars = 20 μm for A and 10 μm for B.
- Figure 5.
Relative retention of [3H]NAA in PINox BY-2 tobacco cells. A and B, Relative accumulation of [3H]NAA by PIN5ox (ProTA:PIN5-GFP1; A) and PIN8ox (ProTA:PIN8-GFP; B). Expression of transgenes was induced by 0.01 mm Dex for 24 h (−Dex = noninduced). Data represent means ± se from eight replicates.
- Figure 6.
IAA restores root hair growth of PINox transformants. A, Representative root images of control (Cont; Columbia-0) and root-hair-specific PIN-overexpressing (PINox; ProE7:PIN-GFP) plants. Seedlings were treated with 50 nm IAA for 1 d. Bar = 100 μm for all. B, Root hair lengths of control and PINox plants. Two independent homozygous lines for each transformant were analyzed. Data represent means ± se (n = 56–112; average = 103).
- Figure 7.
Different root-hair-restoring behaviors of auxin transporter-expressing transformants in response to different auxin species. A, IAA effect on root hair growth of wild-type (WT), ProE7:YFP (YFP), ProE7:AUX1-YFP (AUX1ox), ProE7:PIN2-GFP (PIN2ox), ProE7:PIN3-GFP (PIN3ox), and ProE7:PGP4-YFP (PGP4ox) plants. B, The effect of 2,4-D on root hair growth. C, NAA effect on root hair growth. Root hair length was estimated from five independent experiments, each including 50 to 100 root hairs from five to 10 roots. Data points are means ± se (n = 320–430 [average = 380] for A; n = 270–430 [average = 370] for B; n = 310–430 [average = 380] for C).
- Figure 8.
NPA restores root hair growth of PINox transformants. A, Representative root images of control (Cont; Columbia-0) and root-hair-specific PINox (ProE7:PIN-GFP) plants treated with 1 μm NPA for 1 d. Bar = 100 μm for all. B, Root hair lengths of control and PINox plants treated with 0, 1, 10, and 50 μm NPA. Two independent homozygous lines for each transformant were analyzed. Data represent means ± se for each line (n = 154–234; average = 191).
- Figure 9.
BFA restores root hair growth of PINox transformants. A, Representative root images of control (Cont; Columbia-0) and root-hair-specific PINox (ProE7:PIN-GFP) plants treated with 0.2 μm BFA for 1 d. Bar = 100 μm for all. B, Root hair length of control and PINox plants treated with 0, 0.2, 0.5, and 1 μm BFA. Two independent homozygous lines for each transformant were analyzed. Data represent means ± se for each line (n = 118–303; average = 184).
- Figure 10.
The BFA effect on PIN trafficking in Arabidopsis root hair and tobacco cells. A, Confocal microscopy images of root hair cells from Arabidopsis transformant (ProE7:PIN-GFP) seedlings. B, Confocal microscopy images of transgenic (ProTA:PIN-GFP) tobacco cells. Seedlings and cells were treated with 50 μm BFA for 2 h and with 2 μm FM4-64 for 15 min before observation. GFP signals (left) and FM4-64 signals (middle) were merged in the right panels for each PIN. BFA compartments are indicated by arrows. Bars = 10 μm for all.
- Figure 11.
PIN8 localizes in the cell plate. Confocal microscopy images of transgenic tobacco cells (ProTA:PIN3-GFP, ProTA:PIN5-GFP1, and ProTA:PIN8-GFP). Cells were treated with 50 μm BFA for 2 h and with 2 μm FM4-64 for 15 min before observation. GFP signals (left) and FM4-64 signals (middle) were merged in the right panels for each PIN. The arrows indicate PIN-residing cell plates (for PIN3 and PIN8, but not for PIN5). Bar = 10 μm for all.
- Figure 12.
TIR1-mediated nuclear events are implicated in root hair growth. A, Representative root images of control (Cont; ProE7:GFP) and root-hair-specific TIR1ox (ProE7:TIR1) transformants. Bar = 100 μm for both. B, Root hair lengths of control and TIR1ox plants. The root hair length value of TIR1ox is a mean of values from five independent homozygous lines (Supplemental Fig. S3). Data represent means ± se (n = 200 for control and 1,000 for TIR1ox).
Additional Files
Supplemental Data
Supplemental Figures and Table
Files in this Data Supplement:
- Supplemental Data - Supplemental Figures 1-4 and Supplemental Table
