Infectious diseases are one of the major drivers of coral reef decline worldwide. White plague-like disease (WPL) is a widespread disease with a complex etiology that infects several coral species, including the Brazilian endemic species Mussismilia braziliensis. Gene expression profiles of healthy and WPL-affected M. braziliensis were analyzed in winter and summer seasons. The de novo assembly of the M. braziliensis transcriptome from healthy and white plague samples produced a reference transcriptome containing 119,088 transcripts. WPL-diseased samples were characterized by repression of immune system and cellular defense processes. Autophagy and cellular adhesion transcripts were also repressed in WPL samples, suggesting exhaustion of the coral host defenses. Seasonal variation leads to plasticity in transcription with upregulation of intracellular signal transduction, apoptosis regulation, and oocyte development in the summer. Analysis of the active bacterial rRNA indicated that Pantoea bacteria were more abundant in WPL corals, while Tistlia, Fulvivirga, and Gammaproteobacteria Ga0077536 were more abundant in healthy samples. Cyanobacteria proliferation was also observed in WPL, mostly in the winter. These results indicate a scenario of dysbiosis in WPL-affected M. braziliensis, with the loss of potentially symbiotic bacteria and proliferation of opportunistic microbes after the start of the infection process.

传染病是全球珊瑚礁衰退的主要驱动因素之一。白鼠疫样疾病 (WPL) 是一种广泛存在的疾病，其病因复杂，可感染多种珊瑚物种，包括巴西特有物种Mussismilia braziliensis。在冬季和夏季分析了健康和受 WPL 影响的M. braziliensis 的基因表达谱。M. braziliensis 的从头组装来自健康和白鼠疫样本的转录组产生了一个包含 119,088 个转录本的参考转录组。WPL 患病样本的特征是抑制免疫系统和细胞防御过程。自噬和细胞粘附转录本在 WPL 样本中也受到抑制，表明珊瑚宿主防御力已耗尽。季节性变化导致转录的可塑性，夏季细胞内信号转导、细胞凋亡调节和卵母细胞发育的上调。活性细菌 rRNA 的分析表明，泛菌在 WPL 珊瑚中含量更高，而Tistlia、Fulvivirga和Gammaproteobacteria Ga0077536 在健康样本中含量更高。在 WPL 中也观察到蓝藻增殖，主要是在冬季。这些结果表明，在受 WPL 影响的巴西分枝杆菌中存在生态失调的情况，在感染过程开始后，潜在共生细菌的丧失和机会性微生物的增殖。