Fig 1.
Phylogenetic analysis of expansins from Arabidopsis, poplar, rice, and potato.
The evolutionary tree of expansin were constructed by MEGA7 software, using ClustalW alignment, Maximum Likelihood method, Equal input model, Bootstrap method, and 1,000 repetitions. The expansins in Arabidopsis, poplar, rice, and potato were presented in green, grey, red, and purple words, respectively.
Table 1.
Description of expansin's genes identified from potato genome.
Fig 2.
Phylogenetic relationships and structure of potato expansin genes (StEXPs).
a, phylogenetic relationship. b, exon and intron are indicated by green box and black line, respectively. c, Motif, predicted by MEME online tool. A total of 16 kinds of motifs were found in the 36 StEXPs (e-value<0.05). Each gene contained 6–10 motifs, and the X-axis indicated the predicted amino acid no.
Fig 3.
The chromosome positions of potato expansin genes (StEXP).
The genes at two ends of blue line mean the potential partial duplicated expansin gene pairs (StEXPA8 and StEXPA14, StEXPA11 and StEXPA17, StEXPA13 and StEXPA20, and StEXLB3 and StEXLB4). The blue triangle indicates the four tandem repeated genes (StEXPA21, StEXPA22, StEXPA23 and StEXPA24).
Fig 4.
Expression profiles of potato expansin genes (StEXP).
a, the expression patterns of StEXPs in the tissues of heterozygous diploid Solanum tuberosum, RH89-039-16. b, the expression patterns of StEXPs in doubled monoploid S. tuberosum Group Phureja clone, DM1-3. The whole plant in vitro was respectively treated for 24 hours by 50 μmol L-1 ABA, 10 μmol L-1 IAA, 50 μmol L-1 GA3, and 10 μmol L-1 BAP. c. the expression patterns of StEXPs in DM1-3. The whole plant in vitro was exposured to 150 mmol L-1 NaCl, 260 μmol L-1 Mannitol, 35°C high temperature, respectively, or three separate detached leaves of the plant was spray inoculated by Phytophthora infestans, BABA and BTH, respectively [33]. All FPKM = 0 of transcripts were replaced by FPKM = 0.01, and the FPKM data in Fig 4A and 4B was undergone a log2 (FPKMTreatment / FPKMControl) transformation.
Table 2.
The expression levels of potato expansin genes (StEXPs) under hormone and stress treatments.
Fig 5.
The co-expression network of potato expansin genes (StEXP).
The dash or solid lines indicate weight value of edges between 0.85 and 0.90 or >0.90.
Table 3.
Function of protein involved in co-expression network.
Fig 6.
Expression profiles of potato expansin-like genes under various abiotic stresses.
Values represent mean± standard deviation of three replicates. Different letters indicate significant differences by Tukey's test (P < 0.05) using PROC ANOVA in SAS 9.4.
Fig 7.
Expression profiles of co-expression network involved genes under various abiotic stresses.
a, StEXPA7 and 3 of its directly adjacent genes. b, StEXPA18 and its directly adjacent genes. c, 4 directly adjacent genes to StEXLB2. Values represent mean± standard deviation of three replicates. Different letters indicate significant differences by Tukey's test (P < 0.05) using PROC ANOVA in SAS 9.4.
Table 4.
Pearson's correlation coefficient of StEXPA7, EXT1, ADF2 and an unknown function gene.
Table 5.
Pearson's correlation coefficient of StEXPA18, POE1, PME and CPOD1.
Table 6.
Pearson's correlation coefficient of StEXLB2, ERF, APOD, CP and miraculin.