Transcriptional response to spatial learning and foraging in honey bees: molecular bases for adult neuroplasticity

An important goal of neuroscience research is to discover molecular processes that enable persistent neuroplasticity in the adult and aging brain. In many species, some types of neuroplasticity typically decrease with age. Honey bees and other social hymenopterans, however, exhibit a reinstatement of structural plasticity in association with flight and foraging behavior. Adult plasticity in these species often includes growth and remodeling of processes in the mushroom bodies, a paired region of the insect brain involved in sensory integration, learning and memory. Honey bees (Apis mellifera) learn to navigate in the environment surrounding the hive by performing orientation flights for several days before they begin to forage; both orientation flights and foraging are cognitively challenging behaviors. Honey bee mushroom bodies show increases in neuropil volume coincident with the increased cognitive demands of orientation flights and foraging behavior, and treatment with pilocarpine, a muscarinic cholinergic receptor agonist, produces growth of the mushroom body neuropil comparable to that produced by maturation and foraging. I have examined molecular processes associated with flight and foraging experience in the mushroom bodies of honey bees to discover mechanisms that may support neuropil growth. Foraging experience regulates multiple molecular processes in the mushroom bodies, including some that may contribute directly to neuropil growth, and others that could potentially protect the brain from the effects of aging and physiological stress. My investigation of a specific behavior, the orientation flight, found that this experience triggers a rapid and transient upregulation of egr in the mushroom bodies. Egr is a homolog of egr-1, an immediate-early gene well known to respond to novel experience that also exhibits higher basal levels in brain regions undergoing development or remodeling in vertebrates. I found that egr expression was upregulated in bees prepared to perform orientation flights and in foragers relative to hive bees engaged in brood care, and established its plausibility as a link between muscarinic signaling and neuropil growth.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Neuroscience

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2013

Author dc:creator

• Lutz, Claudia

Contributors dc:contributor

• Newmark, Phillip A.
• Robinson, Gene E.
• Clayton, David F.
• Korol, Donna L.

• Honey bees
• mushroom bodies
• gene expression
• neuroplasticity

Statement dc:rights

• Contents of Chapter 2 were previously published in Developmental Neurobiology, and copyright has been transferred to Wiley-Blackwell. A blanket permission to reprint first author material as part of a thesis is listed here: http://authorservices.wiley.com/bauthor/faqs_copyright.asp#1.7. All other contents copyright 2012 Claudia Lutz.

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/42153

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/42153