Heterologous Expression of CLIBASIA_03915/CLIBASIA_04250 by Tobacco Mosaic Virus Resulted in Phloem Necrosis in the Senescent Leaves of Nicotiana benthamiana

• Published in: International journal of molecular sciences Vol. 21; no. 4; p. 1414
• Main Authors: Li, Hui, Ying, Xiaobao, Shang, Lina, Redfern, Bryce, Kypraios, Nicholas, Xie, Xuejun, Xu, FeiFei, Wang, Shaopeng, Zhang, Jinghua, Jian, Hongju, Yu, Hongtao, Lv, Dianqiu
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI 19.02.2020; MDPI AG
• Subjects: Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Citrus - metabolism; Host-Pathogen Interactions - genetics; huanglongbing; Nicotiana - virology; Nuclear Localization Signals - genetics; Nuclear Localization Signals - metabolism; Phloem - genetics; Phloem - metabolism; Phloem - virology; phloem necrosis; Plant Diseases - microbiology; Plant Leaves - genetics; Plant Leaves - growth & development; Plant Necrosis and Chlorosis - genetics; Plant Proteins - metabolism; protein–protein interaction; Rhizobiaceae - genetics; Rhizobiaceae - pathogenicity; subcellular localization; Tobacco Mosaic Virus - metabolism; virulence factor; Virulence Factors - genetics; Virulence Factors - metabolism; protein–protein interaction; virulence factor; Huanglongbing; phloem necrosis; subcellular localization
• ISSN: 1422-0067; 1422-0067
• DOI: 10.3390/ijms21041414

Huanglongbing (HLB), also known as citrus greening, is the most notorious citrus disease worldwide. Liberibacter asiaticus ( Las) is a phloem-restricted bacterium associated with HLB. Because there is no mutant library available, the pathogenesis of Las is obscure. In this study, we employed TMV) to express two mature secretion proteins CLIBASIA_03915 (m03915) and CLIBASIA_04250 (m04250) in ( ). Phloem necrosis was observed in the senescent leaves of that expressed the two low molecular weight proteins, while no phloem necrosis was observed in the plants that expressed the control, green fluorescent protein (GFP). Additionally, no phloem necrosis was observed in the senescent leaves of that expressed the null mutation of m03915 and frameshifting m04250. The subcellular localizations of m03915 and m04250 were determined by fusion with GFP using confocal microscopy. The subcellular localization of m03915 was found to be as free GFP without a nuclear localization sequence (NLS). However, m04250 did have an NLS. Yeast two-hybrid (Y2H) was carried out to probe the citrus proteins interacting with m03915 and m04250. Six citrus proteins were found to interact with m03915. The identified proteins were involved in the metabolism of compounds, transcription, response to abiotic stress, ubiquitin-mediated protein degradation, etc. The prey of m04250 was involved in the processing of specific pre-mRNAs. Identification of new virulence factors of Las will give insight into the pathogenesis of Las, and therefore, it will eventually help develop the HLB-resistant citrus.