3.2 Gene expressions
The gene expressions and KEGG functional enrichment results for each
region under different soil moisture treatments were shown in Figs. 1 &
2. For individuals from the eastern region, gene expressions were
significantly enriched in photosynthesis-antenna proteins, RNA
degradation, spliceosome, and photosynthesis (Figs. 2a-c). Specifically,
gene expressions were enriched in sulphur metabolism pathway and
phenylalanine, tyrosine and tryptophan biosynthesis pathway under the
light drought treatment (Fig. 2b), and in porphyrin and chlorophyll
metabolism, thiamine metabolism, fructose and mannose metabolism
pathways under the heavy drought treatment (Fig. 2c).
For individuals from the middle region, gene expressions were mainly
enriched in photosynthesis-antenna proteins, RNA degradation,
spliceosome, and photosynthesis (Figs. 2d-f). Specifically, gene
expressions were enriched in basal transcription factors, circadian
rhythm-plant, and ribosome biosynthesis in eukaryotes pathways under the
heavy drought treatment (Fig. 2f).
For individuals from the western region, gene expressions were mainly
enriched in photosynthesis-antenna proteins, spliceosome, and
photosynthesis (Figs. 2g-i). Specifically, gene expressions were
enriched in RNA degradation under the light drought treatment (Fig. 2h),
and in protein processing in endoplasmic reticulum and ubiquitin
mediated proteolysis pathways under the heavy drought treatment (Fig.
2i).
Results of heatmaps and the dendrogram showed that individuals from the
eastern and middle regions showed higher similarity and grouped into one
subgroup under the same soil moisture treatments. Individuals from the
eastern region under the heavy drought treatment showed higher
similarity with those from two other regions under the light drought
treatment. Individuals from the western region under both control and
light drought treatments showed higher similarity, and this subgroup was
clustered with another subgroup that included the eastern and middle
regions under the control treatment (Fig. 3).