Table 1.
Wheat expansin genes identified in this study.
Fig 1.
Phylogenetic analysis of wheat expansins.
a. Phylogenetic tree of the 128 expansin sequences; b. Evolutionary branches of wheat expansins; c. Analysis of gene structure, coding domain sequences (CDSs), 5’/3’ untranslated region and exson/introns; d. Motif analysis of the 128 expansin sequences.
Fig 2.
Expansin gene expression and subexpression profiles in different tissues. Expression profiles were expressed as transcripts per million.
The subexpression profiles were expressed as reads per kilobase of exon model per Million mapped reads (FPKM). A, B and D represent subgenomes A, B, and D. Columns are labeled to show expansion expression as follows: Rt 1: in root during the cotyledon emergence stage, Rt 2: in root during the three leaf stage, Rt 3: in root during the maximum stem length stage; Sm 1: in stem during the half of flower open stage, Sm 2: in stem at the beginning of stem elongation, Sm 3: in stem during two nodes or internodes visible stages; Lf 1: in leaf during the main shoot and axillary shoots visible at three nodes stage, Lf 2: in stem during cotyledon emergence, Lf 3: in leaf during fruit formation; Ie 1: in inflorescence during the half of flower open stage, Ie 2: in inflorescence during the two nodes or internodes visible stage; Ie 3: in inflorescence at maximum stem length; Ft 1: in fruit during fruit formation (30 to 50% fruit formation), Ft 2: in fruit during fruit formation (70% to final size), Ft 3: in fruit during fruit ripening.
Fig 3.
Heat map of cis-acting elements of expansin genes.
Color indicates the number of cis-acting elements (0–12) in each expansin gene.
Fig 4.
Phenotypic analysis of the wheat cultivars Chinese Spring (CS) and Dongnongdongmai 1 (D1).
a. Morphology of CS and D1 plants (including roots); b. Average root length, node length and third leaf length of CS and D1, unit: cm; c. Morphology of tilling nodes of CS and D1 at the same magnification (unit: mm); d. Average tilling rate and tiller numbers of CS and D1. e. Morphology of CS and D1 plants under 4°C treatment; CK: control (growing at 15°C); f. growth of the third leaf under 4°C treatment.
Fig 5.
RT-qPCR of wheat expansin expressions in CS (blue) and D1 (orange) during the three leaf stage under normal growth condition.
Note that certain genes (such as TaEXPA12 and TaEXPA13) were only shown their expression in CS (blue) and certain other genes (such as TaEXPA23 and TaEXPA24) were only shown their expression in D1 (orange). It indicates that the expression of these genes was only detected in cultivar, but not the other.
Fig 6.
Differential expansin expression in CS and D1 during the three leaf stage at 4°C, compared against the expression at normal growth condition at the same time point.
a–b. roots in CS and D1; c. tillering nodes in CS and D1; d. stem in CS and D1; e. leaves in CS and D1. Results were shown as average of three independent experiments.