2023年4月4日，中国农业科学院蔬菜花卉研究所甘蓝青花菜团队在期刊International Journal of Molecular Sciences（2023 IF=5.6）上发表了题为Comparative T ranscriptome Analysis Reveals a Potential Regulatory Network for Ogura Cytoplasmic Male Sterility in Cabbage (Brassica oleracea L.)的研究论文。论文第一作者是陈立博士，通讯作者是南京农业大学园艺学院的侯喜林教授和中国农业科学院蔬菜花卉研究所的张扬勇研究员。
为了研究orf138和Rfo导入后小孢子发育过程和基因表达的变化，以保持系Ogura CMS不育系、和Ogura CMS恢复系为材料，进行了材料学观察和转录组分析。不同发育阶段的小孢子半薄切片表明，Ogura CMS不育系绒毡层细胞的降解始于四分体时期，而保持系和恢复系的绒毡层细胞的讲解始于双核至三核期，因此，绒毡层细胞的提前讲解可能是导致Ogura CMS不育的原因。转录组分析表明，1287个DEGs在保持系和恢复系中有一致的表达趋势，但是在Ogura CMS中显著下调或显著上调，表明它们可能和Ogura CMS的花粉败育有关。
功能注释表明，1287个核心DEGs包括大量的和花粉发育、氧化磷酸化、碳水化合物、脂质和蛋白代谢有关的基因。进一步的验证表明，与能量代谢有关基因的表达下调导致Ogura CMS花药中ATP含量降低和ROS过量积累。基于这些结果，作者提出了一个甘蓝Ogura CMS的转录调控网络。
即在小孢子发育的四分体时期，甘蓝 Ogura CMS中参与能量代谢途径的关键酶基因显著下调表达，导致 ATP合成受阻和质子过量积累，从而导致细胞内的活性氧含量显著升高，过量的活性氧破坏细胞膜壁，引起了绒毡层细胞的异常 PCD，绒毡层的提前降解导致小孢子因缺乏所需的各种营养物质而停止发育，最终导致花粉败育。
Figure 1. Flower morphology and pollen viability of the maintainer line, Ogura CMS line, andrestorer line.(A,D) Maintainer line 19-616.(B,E) Ogura CMS 19-2167.(C,F) Restorer line FR2202 Bar = 0.5 cm.
Figure 3. Differential expression analysis of nuclear genes. (A–C) The pairwise comparison between
19–616, 19–2167 and FR2202. (D) Analysis of the shared DEGs in 19–616, 19–2167 and FR2202.
Figure 4. Gene ontology analysis of the core DEGs enriched in part IV . (A) The number of DEGs
enriched in the three categories. (B) The expression trends and annotations of the core DEGs.
Figure 5. The expression trends and annotations of DEGs enriched in pollen development (A); energy
metabolism (B); carbohydrate, lipid, and protein metabolism (C); and transcription factors (D).
Figure 6. Mitochondrial biochemical indices among three lines. (A) ATP content. (B) ATPase activity .
(C) H2O2 content. Significant differences between samples labeled with different Roman letters (a, b)
were determined by Turkey’s tests. p < 0.05.
Figure 7. Potential transcriptome-mediated regulation network in cabbage Ogura CMS. PCD, programmed cell death; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; PDC, pyruvate ehydrogenase; CS, citrate synthase; ND, NADH dehydrogenase; SDH, succinate dehydrogenase; CCO, cytochrome c oxidase; ATG8, autophagy-related protein 8; ACD11, accelerated cell death 11; SHT, spermidine hydroxycinnamoyl transferase; CCM, caffeoyl-CoA O-methyltransferase; BGL, Beta-glucosidase; AGP , arabinogalactan protein; STP , sugar transport protein; PME, pectinesterase; PMEI, Pectinesterase inhibitor; NLT, non-specific lipid-transfer protein; PEAM, phosphoethanolamine N-methyltransferase; Ole, Oleosin.
