The molecular interplay of the establishment of an infection - gene expression of Diaphorina citri gut and Candidatus Liberibacter asiaticus

Author(s)

Bento, Flavia Moura Manoel ^[1] ; Darolt, Josiane Cecilia ^{[2, 3]} ; Merlin, Bruna Lais ^[1] ; Pena, Leandro ^{[3, 4]} ; Wulff, Nelson Arno ^{[2, 3]} ; Consoli, Fernando Luis ^[1]

Affiliation

^[1] Univ Sao Paulo, Luiz de Queiroz Coll Agr, Dept Entomol & Acarol, Insect Interact Lab, Ave Padua Dias 11, BR-13418900 Piracicaba, SP - Brazil

^[2] Sao Paulo State Univ UNESP, Inst Chem, Araraquara, SP - Brazil

^[3] Fund Citrus Protect FUNDECITRUS, BR-14807040 Araraquara, SP - Brazil

^[4] Univ Politecn Valencia UPV, CSIC, Inst Biol Mol & Celular Plantas IBMCP, Valencia 46022 - Spain

• Document type: Journal article
• Source: BMC Genomics; v. 22, n. 1 SEP 21 2021.
• Web of Science Citations: 0

Abstract

Background Candidatus Liberibacter asiaticus (CLas) is one the causative agents of greening disease in citrus, an unccurable, devastating disease of citrus worldwide. CLas is vectored by Diaphorina citri, and the understanding of the molecular interplay between vector and pathogen will provide additional basis for the development and implementation of successful management strategies. We focused in the molecular interplay occurring in the gut of the vector, a major barrier for CLas invasion and colonization. Results We investigated the differential expression of vector and CLas genes by analyzing a de novo reference metatranscriptome of the gut of adult psyllids fed of CLas-infected and healthy citrus plants for 1-2, 3-4 and 5-6 days. CLas regulates the immune response of the vector affecting the production of reactive species of oxygen and nitrogen, and the production of antimicrobial peptides. Moreover, CLas overexpressed peroxiredoxin, probably in a protective manner. The major transcript involved in immune expression was related to melanization, a CLIP-domain serine protease we believe participates in the wounding of epithelial cells damaged during infection, which is supported by the down-regulation of pangolin. We also detected that CLas modulates the gut peristalsis of psyllids through the down-regulation of titin, reducing the elimination of CLas with faeces. The up-regulation of the neuromodulator arylalkylamine N-acetyltransferase implies CLas also interferes with the double brain-gut communication circuitry of the vector. CLas colonizes the gut by expressing two Type IVb pilin flp genes and several chaperones that can also function as adhesins. We hypothesized biofilm formation occurs by the expression of the cold shock protein of CLas. Conclusions The thorough detailed analysis of the transcritome of Ca. L. asiaticus and of D. citri at different time points of their interaction in the gut tissues of the host led to the identification of several host genes targeted for regulation by L. asiaticus, but also bacterial genes coding for potential effector proteins. The identified targets and effector proteins are potential targets for the development of new management strategies directed to interfere with the successful utilization of the psyllid vector by this pathogen. (AU)

• FAPESP's process: 15/07011-3 - Biotechnological approaches to the control of citrus huanglongbing using transgenic plants
• Grantee: Leandro Antonio Peña Garcia
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 18/24768-9 - Edaphic mites: diversity, relationship with the microbiota and ecology in natural and agricultural areas in Brazil, with elaboration of databases and keys to identify selected groups
• Grantee: Bruna Laís Merlin
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 18/24234-4 - Genes for the potential control of Diaphorina citri through gene silencing
• Grantee: Flavia de Moura Manoel Bento
• Support Opportunities: Scholarships in Brazil - Post-Doctoral