The Genome of “Candidatus Liberibacter asiaticus” Is Highly Transcribed When Infecting the Gut of Diaphorina citri

Abstract

The Asian citrus psyllid, Diaphorina citri, is the vector of the bacterium “Candidatus Liberibacter asiaticus” (Las), associated with the devastating, worldwide citrus disease huanglongbing. In order to explore the molecular interactions of this bacterium with D. citri during the vector acquisition process, cDNA libraries were sequenced on an Illumina platform, obtained from the gut of adult psyllids confined in healthy (H) and in Las-infected young shoots (Las) for different periods of times (I = 1/2 days, II = 3/4 days, and III = 5/6 days). In each sampling time, three biological replicates were collected, containing 100 guts each, totaling 18 libraries depleted in ribosomal RNA. Reads were quality-filtered and mapped against the Chinese JXGC Las strain and the Floridian strain UF506 for the analysis of the activity of Las genome and SC1, SC2, and type 3 (P-JXGC-3) prophages of the studied Las strain. Gene activity was considered only if reads of at least two replicates for each acquisition access period mapped against the selected genomes, which resulted in coverages of 44.4, 79.9, and 94.5% of the JXGC predicted coding sequences in Las I, Las II, and Las III, respectively. These genes indicate an active metabolism and increased expression according to the feeding time in the following functional categories: energy production, amino acid metabolism, signal translation, cell wall, and replication and repair of genetic material. Pilins were among the most highly expressed genes regardless of the acquisition time, while only a few genes from cluster I of flagella were not expressed. Furthermore, the prophage region had a greater coverage of reads for SC1 and P-JXGC-3 prophages and low coverage in SC2 and no indication of activity for the lysis cycle. This research presents the first descriptive analysis of Las transcriptome in the initial steps of the D. citri gut colonization, where 95% of Las genes were active.

Sub-optimal temperatures lead to altered expression of stress-related genes and increased ‘Candidatus Liberibacter solanacearum’ accumulation in potato psyllid

“…Other B. cockerelli gene products are implicated as ‘Ca. L. solanacearum ’ -effector interactors with predicted functions in attachment/invasion/exocytosis, and potentially salivary glands entry ( 65 , 73 , 84 , 91 , 92 ). The RNAseq differential expression profiles reported here provide the first snapshots into host-pathogen thermal adaptation mechanisms and highlight key biochemical pathways in its insect host, apparently essential for ‘Ca.…”

Possible economic losses on the oranges production chain of Peru due to introduction of Huanglongbing (HLB): Simulation of prospective scenarios to 2045

“…Introduction Huanglongbing (HLB), also known as "Yellow Dragon" or "Citrus Greening," is a bacterial disease that affects citrus trees. The causative agent is a gram-negative, persistent, and propagative bacteria (Aidoo et al, 2023;Darolt et al, 2021;Nguyen et al, 2023;Stover et al, 2018). In the Americas, the Candidatus Liberibacter americanus strain is prevalent (Bové et al, 2006;Clarke & Brown, 2018;De Chaves et al, 2023;Hansen et al, 2022).…”