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ARS Home » Southeast Area » Fort Pierce, Florida » U.S. Horticultural Research Laboratory » Subtropical Insects and Horticulture Research » Research » Publications at this Location » Publication #321797
Title: Discovery of huanglongbing (HLB) pre-symptomatic Ribonucleic acid (RNA) biomarkers

Author
item WREN, M - Los Alamos National Research Laboratory
item PARDINGTON, P - Los Alamos National Research Laboratory
item Stover, Eddie
item GUPTA, G - Los Alamos National Research Laboratory

Submitted to: American Association for Immunology
Publication Type: Abstract Only
Publication Acceptance Date: 1/11/2015
Publication Date: 5/1/2015
Citation: Wren, M., Pardington, P.E., Stover, E.W., Gupta, G. 2015. Discovery of huanglongbing (HLB) pre-symptomatic Ribonucleic acid (RNA) biomarkers. American Association for Immunology. www.jimmunol.org/content/194/1_Supplement/127.20.

Interpretive Summary:

Technical Abstract: Huanglongbing (HLB) is the most devastating citrus disease and is associated with vector-borne Liberibacter. Currently there is no cure for huanglongbing. Visual disease symptoms appear in only a few leaves months after initial Liberibacter exposure compromising disease management by tree removal. Since infected but non-symptomatic trees are inoculum sources, a robust platform for early diagnosis of huanglongbing is urgently needed. Here, we describe our studies on the discovery of huanglongbing pre-symptomatic Ribonucleic acid (RNA) biomarkers. For this, we infected greenhouse citrus using Liberibacter inoculum delivered by psyllid vectors confined to branch cages for a single week. Total Ribonucleic acid was extracted from leaves at three distances from the point of inoculation and for a range of early post-exposure times. Gene expression data by Ribonucleic acid-seq was collected for all leaf samples. We expect citrus genes belonging to pattern recognition, plant hormone, and stress pathways to be expressed early during infection. The Ribonucleic acid-seq data will be analyzed to identify which citrus genes are altered in leaves during early infection. It is our hypothesis that pre-symptomatic citrus biomarkers will be systemically expressed during the early stages of infection even in leaves distant from the site of Liberibacter inoculation. We will validate the expression of the candidate pre-symptomatic biomarkers by quantitative polymerase chain reaction (qPCR). The candidate biomarkers will reflect citrus genes that are systemically expressed and the Liberibacter genes that are indicative of bacterial growth.