Darolt Josiane Cecília, Bento Flavia de Moura Manoel, Merlin Bruna Laís, Peña Leandro, Cônsoli Fernando Luis, Wulff Nelson Arno
Instituto de Química, Universidade Estadual Paulista "Julio de Mesquita Filho" - UNESP, Araraquara, Brazil.
Departamento de Pesquisa & Desenvolvimento, Fundo de Defesa da Citricultura - Fundecitrus, Araraquara, Brazil.
Front Microbiol. 2021 Jul 12;12:687725. doi: 10.3389/fmicb.2021.687725. eCollection 2021.
The Asian citrus psyllid, , is the vector of the bacterium " Liberibacter asiaticus" (Las), associated with the devastating, worldwide citrus disease huanglongbing. In order to explore the molecular interactions of this bacterium with 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 gut colonization, where 95% of Las genes were active.
亚洲柑橘木虱是与毁灭性的全球柑橘病害黄龙病相关的“亚洲韧皮杆菌”（Las）的传播媒介。为了探究该细菌在传播媒介获取过程中与亚洲柑橘木虱的分子相互作用，在Illumina平台上对从分别在健康（H）和感染Las的嫩梢（Las）中饲养不同时间段（I = 1/2天，II = 3/4天，III = 5/6天）的成年木虱肠道中获得的cDNA文库进行了测序。在每个采样时间，收集了三个生物学重复样本，每个样本包含100个肠道，总共18个去除核糖体RNA的文库。对读取的序列进行质量过滤，并与中国JXGC Las菌株和佛罗里达菌株UF506进行比对，以分析Las基因组以及所研究Las菌株的SC1、SC2和3型（P-JXGC-3）前噬菌体的活性。仅当每个获取时间段至少两个重复样本的读取序列与选定基因组比对上时，才考虑基因活性，这分别导致Las I、Las II和Las III中JXGC预测编码序列的覆盖率为44.4%、79.9%和94.5%。这些基因表明在以下功能类别中，根据取食时间，代谢活跃且表达增加：能量产生、氨基酸代谢、信号转导、细胞壁以及遗传物质的复制和修复。无论获取时间如何，菌毛蛋白都是表达量最高的基因之一，而鞭毛簇I中只有少数基因未表达。此外，前噬菌体区域中SC1和P-JXGC-3前噬菌体的读取序列覆盖率更高，而SC2的覆盖率较低，并且没有裂解周期活性的迹象。本研究首次对Las在亚洲柑橘木虱肠道定殖初始阶段的转录组进行了描述性分析，其中95%的Las基因具有活性。
