Development of wild-type (WT), ΔPpXLG, and ΔPpGβ2 P. patens plants. Protonemata growth of 1-week-old P. patens (A) wild-type (WT; B), ΔPpXLG (C), and ΔPpGβ2 and 24-d-old gametophores of WT (D), ΔPpXLG (E), and ΔPpGβ2 (F) on BCD medium. G, WT, ΔPpXLG, and ΔPpGβ2 plants at 44 d showing impaired elongation of mutants. Scale bar = 500 µm. H, Quantification of gametophore length after 6 weeks of growth on BCD medium (n = 12). Mean value and SD are plotted. Significance was calculated using t test for unequal variances (P < 0.001).