Relative receptor gene expression in wild type and ethylene receptor mutants. (A) expression of remaining wild-type receptor genes in receptor mutants relative to total receptor gene expression in wild type (Col-0). P value indicates the probability of a numerically larger value of t for the comparison (Student's t test) between two isogenic mutants highlighted with a box. (B), (C), (D), and (E) expression of individual receptor genes in isogenic receptor mutants relative to that in wild type. Box highlights the common receptor gene mutations of a set of isogenic mutants. Error bars indicate standard deviation. n = 3 × 3: each measurement was repeated three times from three independent biological materials. NA: the ERS1 expression is not measured in ers1 mutants. P: probability of a numerically larger value of t in a LSD-t test.