Figure 1.

Basally localized PIN1 in pid mutant meristem likely transports auxin basally

(A) PIN1::PIN1-GFP expression (magenta) in wild type inflorescence meristem.

(B) PIN1::PIN1-GFP expression in pid-4 mutant inflorescence meristem. Basal PIN1 polarity away from meristem center marked by arrowhead.

(C) pid-4 PIN1-GFP inflorescence meristem forming floral organ tissue 3 days after 10μM NPA treatment. Lower image shows longitudinal optical section of the meristem corresponding to line in top image. Arrows indicate organ primordia.

(D) Mock-treated pid-4 PIN1-GFP inflorescence.

(E) pid-4 PIN1-GFP apex treated with 10μM NPA for 7 days. Arrows indicate floral primordia.

(F) Graph showing number of organ primordia produced from the pid-4 mutant apex after NPA and mock treatments (n = 12). Error bar represents SE of mean.

(G) Graph showing frequency of organ outgrowth from the pin-like inflorescences of pid-4 mutant after local application of NPA in lanoline paste (n=9) and mock treatments (n=5).

(H) Mock treated pid-4 PIN1-GFPinflorescence.

(I) pid-4 PIN1-GFP apex treated with 10µM NPA in lanoline paste. Arrow indicates organ primordia.

Scale bar = 100 μm (A), 20 μm (B–C).