Table 4_Identification and characteristics of differentially expressed genes under UV-B stress in Gossypium hirsutum.xlsx

ObjectiveThis study aimed to screen the differentially expressed genes (DEGs) of Gossypium hirsutum under UV-B stress and identify the significant pathways based on gene enrichment analysis results.
MethodsIn this study, the allotetraploid crop G. hirsutum was used to examine changes in various physiological indexes under UV-B stress, and screened out all DEGs under UV-B stress (16 kJ m-2 d-1) based on six leaf transcriptomes. The main enrichment pathways of DEGs were analyzed according to gene annotation. Finally, we predicted the regulatory genes of phenylpropanoid pathway under UV-B stress by co-expression network analysis, and selected GhMYB4 for verification.
ResultsGene annotation analysis revealed that DEGs were predominantly enriched in pathways related to photosynthesis and secondary metabolism. Further analysis revealed that UV-B stress impaired photosynthesis mainly by damaging photosystem II (PSII) and inhibiting electron transport, whereas G. hirsutum responded to UV-B stress by synthesizing secondary metabolites such as anthocyanins and lignin. We selected the regulatory genes GhMYB4 for verification. It was found to be an anthocyanin negative regulator in response to UV-B stress.
ConclusionsUV-B stress impaired photosynthesis mainly by damaging photosystem II (PSII) and inhibiting electron transport, whereas G. hirsutum responded to UV-B stress by synthesizing secondary metabolites such as anthocyanins and lignin.

研究目的：本研究旨在筛选UV-B胁迫下陆地棉（Gossypium hirsutum）的差异表达基因（differentially expressed genes, DEGs），并基于基因富集分析结果识别显著富集的通路。
研究方法：本研究以异四倍体作物陆地棉为实验材料，检测其在UV-B胁迫下的各项生理指标变化；基于6份叶片转录组数据，筛选出16 kJ·m⁻²·d⁻¹强度UV-B胁迫下的全部差异表达基因。通过基因注释分析差异表达基因的主要富集通路，最终通过共表达网络分析预测UV-B胁迫下苯丙烷通路的调控基因，并选取GhMYB4进行验证。
研究结果：基因注释分析显示，差异表达基因主要富集于光合作用与次生代谢相关通路。进一步分析表明，UV-B胁迫主要通过损伤光系统II（photosystem II, PSII）并抑制电子传递破坏光合作用过程；而陆地棉则通过合成花青素、木质素等次生代谢产物响应UV-B胁迫。本研究选取调控基因GhMYB4进行验证，发现其为响应UV-B胁迫的花青素负调控因子。
研究结论：UV-B胁迫主要通过损伤光系统II（PSII）并抑制电子传递破坏光合作用，而陆地棉通过合成花青素、木质素等次生代谢产物响应UV-B胁迫。