2013 Annual Report
1a.Objectives (from AD-416):
Investigate the cause(s) of collapse of managed European honey bees, Apis mellifera L. and find appropriate strategies to reduce colony loss. A USDA AFRI Coordinated Agricultural Project (CAP), granted to the University of Georgia, has two objectives that directly relate to the ARS interest:.
1)investigate the epidemiology and pathogenesis of Israeli Acute Paralysis Virus (IAPV), a virus that was found to be strongly associated with Colony Collapse Disorder (CCD, and develop RNA interference (RNAi) therapeutics for the treatment of the viral disease; and.
2)develop diagnostic tools for high-throughput detection and monitoring of honey bee diseases. The cooperator (representing a consortium of researchers on the funded AFRI grant) is interested in the synergistic interactions between honey bee microsproidian parasites, Nosema and viruses. ARS-BRL will work with the cooperators of the grant toward these common objectives.
1b.Approach (from AD-416):
We will use genomic approaches to:.
1)investigate the transmission routes of IAPV in honey bees;.
2)determine the spread and replication of IAPV infection under different host physiological conditions, develop the host genetic markers for diseases;.
3)develop RNAi-based l therapeutics for the treatment of viral diseases; and.
4)develop an economic screening tool and streamlined screening system for high-throughput detection and monitoring of honey bee diseases.
Honey bee colonies are suffering from numerous parasites and pathogens which are significant threats to the health and well-being of honey bees. Among the pathogens attacking honey bees, viruses are probably the least understood because of the lack of information about the dynamics underlying viral disease outbreaks. In the recent years, honey bee colonies across the U.S, and around the world have declined dramatically, in part due to a a poorly understood malady labeled Colony Collapse Disorder (CCD). IAPV was identified to be strongly associated with CCD and is considered to be a significant marker for CCD. Therefore, gaining knowledge of the transmission and epidemiology of this virus is an integral part of the study of viral disease outbreaks and the development of environmentally friendly disease management strategies. In addition, it is important to develop genetic diagnostic tools for identifying the pathogens and defining disease threats to honey bees.
Our specific focus areas in past year (2012-2013) included identification of an IAPV-encoded putative suppressor of RNA interference (RNAi), and evidence that RNAi-based silencing this suppressor reduces IAPV replication, contributing a novel therapeutic strategy for limiting IAPV and colony losses due to viral diseases. A second focus was the identification that an immune pathway, JAK-STAT pathway, along with other signaling events such as the mTOR and MAPK pathways, was implicated in antiviral responses by honey bees toward IAPV. The research resulting from these efforts has been disseminated to state and federal regulators, stakeholders, and other researchers via presentations, diagnostic reports, and publications in trade and research journals.