Extended Data Fig. 1: Promoter activity analysis using the nuclear marker H2B-GFP expressed by the NTL11 promoter.
From: EGG CELL 1 contributes to egg-cell-dependent preferential fertilization in Arabidopsis
a-d, NTL11 promoter-driven H2B-GFP reporter fluorescence in nuclei of roots (a), root hairs (b), leaves (c), and trichomes (d), respectively. e, NTL11 promoter activity analysis during male gametophyte development. The H2B-GFP signals were visible in the microspore nucleus (MN), and in the generative cell nucleus (GN) and the vegetative cell nucleus (VN) of bicellular pollen (BC). In tricellular pollen (TC), the reporter signal became weak in the VN. In contrast, the signal remained persistently detectable in the sperm nuclei (SN) of tricellular pollen and germinated pollen tubes. f, Quantification of the GFP signal intensity shown in e from the microspore stage to the tricellular pollen stage (n = 22, 32, 32, 30 and 30, from left to right). Identical settings were used for microscopy, fluorophore excitation and detection. The central lines in the box plots represent the median, the box represents the interquartile range (IQR) and the whiskers extend to minima and maxima. Significant differences by two-sided Student’s t-test are indicated. g, NTL11 promoter-driven H2B–GFP reporter fluorescence in unfertilized and fertilized ovules. The H2B-GFP signals were visible in the egg cell nucleus (ECN), the central cell nucleus (CCN) and synergid cell nucleus (SCN) in mature ovules and could be detected in the zygote nucleus (ZYN) and endosperm nucleus (ESN) after fertilization. Scale bars, 25 µm in a, 10 µm in b and g, 20 µm in c, 60 µm in d and 4 µm in e.
