Grant Information
| Knowledge Area | Subject of Investigation | Field of Science | Percent |
|---|---|---|---|
| 212 - Pathogens and Nematodes Affecting Plants | 910 - Grapefruit | 1040 - Molecular biology | 50% |
| 212 - Pathogens and Nematodes Affecting Plants | 920 - Orange | 1060 - Biology (whole systems) | 50% |
Characterize the hypl gene and determine its effects on insect transmission and/or virulence in host plants. The objectives of the original proposal include:
Transient expression with alternative expression systems and RT-qPCR, etc., will be used to elucidate the function of the hypl gene of Las and shed the light on the molecular mechanism of this "phase variation" phenomenon and thereby develop a novel control strategy for citrus HLB. In addition, antibodies and probes along with standardized protocols, developed during this project can be applied for better detection and differentiation of the HLB bacteria.
Transient expression with alternative expression systems and RT-qPCR, etc. , will be used to elucidate the function of the hypl gene of Las and shed the light on the molecular mechanism of this "phase variation" phenomenon and thereby develop a novel control strategy for citrus HLB. In addition, antibodies and probes along with standardized protocols, developed during this project can be applied for better detection and differentiation of the HLB bacteria. This research relates to inhouse project objective: 1. Characterize ecology, biology, epidemiology, molecular genetics, and vector and host (crop and weed) interactions of domestic, exotic, newly emerging, and re- emerging pathogens, and 2. Develop/refine rapid, sensitive reliable detection/sampling methods for pathogens. We have characterized two novel autotransporter proteins of �Candidatus Liberibacter asiaticus� (Las), and redesignated them as LasAI and LasAII in lieu of the previous names HyvI and HyvII. Bioinformatic analyses revealed that LasAI and LasAII share the structural features of an autotransporter family containing large repeats of a passenger domain and a unique C-terminal translocator domain. When fused to the Green fluorescent protein (GFP) gene and expressed in Escherichia coli, the LasAI C-terminus and the full length LasAII were localized to the bacterial poles, similar to other members of autotransporter family. Despite the absence of the signal peptide, LasAI was found to localize at the cell surface by immuno-dot blot using a monoclonal antibody against the partial LasAI protein. Its surface localization was also confirmed by the removal of the LasAI antigen using a proteinase K treatment of the intact bacterial cells. When co-inoculated with a P19 gene silencing suppressor and transiently expressed in tobacco leaves, the GFP-LasAI translocator targeted to the mitochondria of host plants. This is the first report that Las encodes novel autotransporters that target to mitochondria.