Fig. 3: AcRR1 improves floret fertility by activating TaWOX11-2D.
SEM image of young spikes (a) and central florets (b) from Fielder and AcRR1-OE at the pistil and stamen formation stages. Scale bar, a 1 mm; b 0.5 mm. c Comparison of the florets number that eventually formed in Fielder and AcRR1-OE. d GUS histochemical assays of ProAcRR1:GUS during young spike differentiation. I, floret differentiation stage; II, pistil and stamen formation stage; III, anther connective stage; IV, tetrad stage; V, white anther stage. Scale bar, 100 μm. In (a‒d) S, spikelet; F, floret primordia; AP, awn primordia; AF, apical floret; CF, central florets; BF, basal florets; A, anther. e, f Cytokinin and IAA contents of Fielder and AcRR1-OE young spikes at the double ridge stage. g DEGs related to cytokinin degradation and biosynthesis in Fielder and AcRR1-OE young spikes. h Expression of TaWOX11-2D in young spikes of AcRR1-OE lines. i Direct binding of AcRR1 to the TaWOX11-2D promoter. j EMSA of the binding of AcRR1-His to the AGATN (A/T/C) motif in the TaWOX11-2D promoter. k ChIP‒qPCR assay of the binding of AcRR1 to the TaWOX11-2D promoter. l Representative spikes and middle spikelets of Jing 411 and the Tawox11-2D mutant. Scale bar, left, 2 cm; right, 1 cm. The grain number per spikelet (m) and grain number per spike (n) of F2 TaWOX11-2DDD, TaWOX11-2DDd and TaWOX11-2Ddd plants derived from a cross of the Tawox11-2D mutant with Jing 411. o Direct binding of AcRR1 and wheat orthologs to the TaWOX11-2D promoter. The data are presented as the means ± S.D.s. In (e‒i, k, o) n = 3 biologically independent replicates. In (c, m, n) n represents the number of biologically independent plants. A two-tailed Student’s t test was used to determine P values. Source data are provided as a Source Data file.
