The Basic Leucine Zipper Transcription Factor PlBZP32 Associated with the Oxidative Stress Response Is Critical for Pathogenicity of the Lychee Downy Blight Oomycete Peronophythora litchii
The Basic Leucine Zipper Transcription Factor PlBZP32 Associated with the Oxidative Stress Response Is Critical for Pathogenicity of the Lychee Downy Blight Oomycete Peronophythora litchii
复制标题
与氧化应激反应相关的碱性亮氨酸拉链转录因子 PlBZP32 对于荔枝霜霉病卵菌荔枝霜霉病的致病性至关重要。
DOI：
10.1128/msphere.00261-20
复制
发表时间：
2020-05-01
期刊：
影响因子：
4.8
通讯作者：
Xi, Pinggen
中科院分区：
文献类型：
--
作者：
Kong, Guanghui;Chen, Yubin;Xi, Pinggen
碱性亮氨酸拉链（bZIP）转录因子广泛存在于真核生物中，包括植物、动物、真菌和卵菌。然而，bZIPs在卵菌中的功能很少有人知道。在本研究中，我们鉴定了荔枝霜疫霉中具有特殊bZIP-PAS结构的bZIP蛋白，命名为PlBZP 32。我们发现PlBZP 32在游动孢子、孢囊和侵入性菌丝生长过程中上调。我们利用RNAi技术研究了PlBZP 32基因的功能。PlBZP 32沉默突变体对氧化胁迫更敏感，表现出较低的孢囊萌发率，并且比野生型菌株SHS 3产生更多的孢子囊。PlBZP 32沉默突变体对宿主植物的侵袭性也较小。此外，我们分析了胞外过氧化物酶和漆酶的活性，发现沉默PlBZP 32降低了荔枝假单胞菌过氧化物酶和漆酶的活性。据我们所知，这是第一个报告，bZIP-PAS蛋白的功能与氧化应激，无性发育，并在卵菌的致病性。重要在这项研究中，我们利用RNAi技术研究的功能，具有碱性亮氨酸拉链（bZIP）-PAS结构的PlBZP 32，并提供见解的贡献bZIP转录因子的氧化应激，荔枝霜疫霉孢子囊的产生、孢囊的萌发及致病性。本研究还揭示了PlBZP 32在调节植物病原卵菌胞外过氧化物酶和漆酶活性中的作用。
Basic leucine zipper (bZIP) transcription factors are widespread in eukaryotes, including plants, animals, fungi, and oomycetes. However, the functions of bZIPs in oomycetes are rarely known. In this study, we identified a bZIP protein possessing a special bZIP-PAS structure in Peronophythora litchii, named PlBZP32. We found that PlBZP32 is upregulated in zoospores, in cysts, and during invasive hyphal growth. We studied the functions of PlBZP32 using the RNAi technique to suppress the expression of this gene. PlBZP32-silenced mutants were more sensitive to oxidative stress, showed a lower cyst germination rate, and produced more sporangia than the wild-type strain SHS3. The PlBZP32-silenced mutants were also less invasive on the host plant. Furthermore, we analyzed the activities of extracellular peroxidases and laccases and found that silencing PlBZP32 decreased the activities of P. litchii peroxidase and laccase. To our knowledge, this is the first report that the functions of a bZIP-PAS protein are associated with oxidative stress, asexual development, and pathogenicity in oomycetes.IMPORTANCE In this study, we utilized the RNAi technique to investigate the functions of PlBZP32, which possesses a basic leucine zipper (bZIP)-PAS structure, and provided insights into the contributions of bZIP transcription factors to oxidative stress, the production of sporangia, the germination of cysts, and the pathogenicity of Peronophythora litchii. This study also revealed the role of PlBZP32 in regulating the enzymatic activities of extracellular peroxidases and laccases in the plant-pathogenic oomycete.