Fig. 4. DEGs analyses and visualizations in corresponding comparisons.

a KEGG enrichment analysis of sex-associated DEGs underlines the phytohormone signal transduction in male flowers when compared to female ones. Auxin-related TIR1/AFBs signaling transduction: auxin was transported by membrane-bound carrier AUX (CpAUX1 encoding) and bound to receptor TIR/AFBs (CpTIR1 encoding). ① Complex containing TIR/AFBs triggered subsequently ubiquitin-mediated proteolysis of AUX/IAA by recruiting proteasome; ② Aux/IAA degradation alleviates the transcript repression of ARF5 gene CpARF5. In the last step, ARF5 bound the DNA elements and promoted the transcription of IAA gene (CpIAA4 and CpIAA6). Ub in yellow circles indicate the degradation of target proteins via the ubiquitin proteasome pathway. b Volcano diagram showing the DEGs in spring male flowers when compared with the spring female counterparts. Each dot represents individual DEG, the red and blue dots indicate upregulated and downregulated sex-associated DEGs in male flowers, respectively; gray dots represent DEGs excluding sex-associated DEGs. Plotted −log₁₀ (P value of DEGs) on the vertical y-axis against log₂ (fold-changes of DEGs) on the horizontal x-axis. Eleven sex-associated DEGs involved in phytohormone signal transduction were marked as green labels, and nine sex-associated DEGs with identical methylation variances were marked as black labels. CpARR5 is earmarked by rectangle as the only phytohormone signal-responsive DEG associated with a hypomethylated methylation variance. Nine other DEGs were CpACP4 (encoding acyl carrier protein 4, two CsDMC in third introns and three CsDMCs in downstream region), CpAPE2 (encoding chloroplast triose phosphate/3-phosphoglycerate translocator, five CsDMCs in promoter), CpGsSRK (encoding G-type lectin S-receptor-like serine/threonine-protein kinase, one CsDMCs in downstream), CpMAGL4 (encoding alpha/beta-Hydrolases superfamily protein, four CsDMCs in third introns and three CsDMCs in downstream), Cp NB-ARC (encoding NB-ARC domain-containing disease resistance protein, three CsDMCs in promoter), CpSBT3.3 (encoding Subtilase family protein, one CsDMCs in fourth exon), CpTFIID (encoding Transcription initiation factor TFIID subunit 8, one CsDMCs in first exon), CpTLC (encoding TRAM, LAG1 and CLN8 lipid-sensing domain-containing protein, one CsDMCs in promoter and one CsDMCs in downstream), CpUNC (encoding uncharacterized conserved protein, one CsDMCs in downstream). For related CsDMCs genomic positions, see Supplementary Table 6