Project description:‘Candidatus Liberibacter asiaticus’ (CLas), the bacterial pathogen associated with citrus greening disease, is transmitted by Diaphorina citri, the Asian citrus psyllid (ACP). We used quantitative mass spectrometry to compare the proteomes of CLas(+) and CLas(-) populations of D. citri. This experiment used adult mixed sex whole insect samples as starting material for protein extraction. DNA extracted from CLas(+) ACP was tested by qPCR to confirm presence of CLas.
Project description:Hemolymph was characterized from Diaphorina citri adults infected with the phytopathogen, Candidatus Liberibacter asiaticus (CLas) and compared with that from uninfected psyllids. This study identified 5531 and 3220 peptides within infected and uninfected hemolymph using nano LC-MS/MS. A reduced number of proteins were detected for D. citri and all known endosymbionts within infected hemolymph as compared to uninfected hemolymph. A large number of immune defense proteins were absent from D. citri hemolymph; however, a single recognition protein (PGRP), two serine protease inhibitors, three prophenoloxidase (proPO) enzymes, and a single serine protease in an uninfected D. citri were detected. The hemolymph is nearly devoid of nutrient storage proteins. This is the first proteomic analysis of D. citri hemolymph that also analyzes the components contributed by all of the endosymbionts. By comparing the contribution of each endosymbiont (CCR, CPA,WB) in the presence and absence of CLas infection, this study provides initial insights regarding the hemolymph response to microbial community shifts associated with D. citri infection status. Our data also present potential protein targets for analysis and disruption of CLas transmission that may facilitate management of huanglongbing (HLB) caused by CLas in citrus.
Project description:Candidatus Liberibacter asiaticus (Las) is an emergent bacterial pathogen associated with the devastating citrus Huanglongbing (HLB), also known as the greening disease. Vectored by the Asian Citrus Psyllid (Diaphorina citri), Las colonizes the phloem tissue of citrus. So far, efforts of cultivating Las in vitro have not been successful and dual-transcriptome analyses could only detect ~100 Las genes due to the low abundance of bacterial RNA in infected citrus/psyllid tissues. Therefore, the biology of this pathogen is poorly understood. Here, we established a procedure to enrich Las RNA for transcriptome analysis in order to obtain insights into the interactions of Las with its two hosts. We were able to confidently determine the expression profiles of >400 Las genes, including 106 that were differentially expressed between citrus and psyllids. Genes related to transcription/translation and defense were found to be upregulated in citrus; whereas genes upregulated in psyllids are involved in metabolic pathways related to tricarboxylic acid (TCA) cycle. Genes encoding the succinate dehydrogenase and NADH quinone oxidoreductase complexes, as well as the flagellar system are also expressed to higher levels in psyllids. We also analyzed the relative expression levels of Sec-delivered effectors, which are considered key virulence factors of Las. This work advances our understanding of the HLB biology and offers novel insight into the HLB pathogenesis.
Project description:‘Candidatus Liberibacter asiaticus’ (CLas), the bacterial pathogen associated with citrus greening disease, is transmitted by Diaphorina citri, the Asian citrus psyllid (ACP). This dataset was obtained from analysis of CLas(-) whole adult ACP samples.
Project description:‘Candidatus Liberibacter asiaticus’ (CLas), the bacterial pathogen associated with citrus greening disease, is transmitted by Diaphorina citri, the Asian citrus psyllid (ACP). This dataset was obtained from analysis of CLas(+) whole nymph ACP samples.
Project description:‘Candidatus Liberibacter asiaticus’ (CLas), the bacterial pathogen associated with citrus greening disease, is transmitted by Diaphorina citri, the Asian citrus psyllid (ACP). This dataset was obtained from analysis of CLas(+) whole adult ACP samples.
