Bi Kai, Chen Tao, He Zhangchao, Gao Zhixiao, Zhao Ying, Fu Yanping, Cheng Jiasen, Xie Jiatao, Jiang Daohong
State Key Laboratory of Agriculture Microbiology, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, People's Republic of China.
Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei Province, People's Republic of China.
BMC Genomics. 2018 Dec 6;19(1):881. doi: 10.1186/s12864-018-5307-4.
The eukaryotic unicellular protist Plasmodiophora brassicae is an endocellular parasite of cruciferous plants. In host cortical cells, this protist develops a unicellular structure that is termed the plasmodium. The plasmodium is actually a multinucleated cell, which subsequently splits and forms resting spores. The mechanism for the growth of this endocellular parasite in host cell is unclear.
Here, combining de novo genome sequence and transcriptome analysis of strain ZJ-1, we identified top five significant enriched KEGG pathways of differentially expressed genes (DEGs), namely translation, cell growth and death, cell communication, cell motility and cancers. We detected 171 proto-oncogenes from the genome of P. brassicae that were implicated in cancer-related pathways, of which 46 were differential expression genes. Three predicted proto-oncogenes (Pb-Raf1, Pb-Raf2, and Pb-MYB), which showed homology to the human proto-oncogenes Raf and MYB, were specifically activated during the plasmodial growth in host cortical cells, demonstrating their involvement in the multinucleate development stage of the unicellular protist organism. Gene networks involved in the tumorigenic-related signaling transduction pathways and the activation of 12 core genes were identified. Inhibition of phosphoinositol-3-kinase relieved the clubroot symptom and significantly suppressed the development process of plasmodia.
Proto-oncogene-related regulatory mechanisms play an important role in the plasmodial growth of P. brassicae.
真核单细胞原生生物芸苔根肿菌是十字花科植物的细胞内寄生虫。在宿主皮层细胞中，这种原生生物形成一种被称为原质团的单细胞结构。原质团实际上是一个多核细胞，随后分裂并形成休眠孢子。这种细胞内寄生虫在宿主细胞中生长的机制尚不清楚。
在此，结合菌株ZJ-1的从头基因组序列和转录组分析，我们鉴定出差异表达基因（DEG）的前五个显著富集的KEGG通路，即翻译、细胞生长与死亡、细胞通讯、细胞运动和癌症。我们从芸苔根肿菌的基因组中检测到171个与癌症相关通路有关的原癌基因，其中46个是差异表达基因。三个预测的原癌基因（Pb-Raf1、Pb-Raf2和Pb-MYB），它们与人类原癌基因Raf和MYB具有同源性，在宿主皮层细胞中原质团生长过程中被特异性激活，表明它们参与了这种单细胞原生生物的多核发育阶段。鉴定出了与致瘤相关信号转导通路相关的基因网络以及12个核心基因的激活情况。抑制磷酸肌醇-3-激酶可缓解根肿病症状并显著抑制原质团的发育过程。
原癌基因相关调控机制在芸苔根肿菌原质团生长中起重要作用。
