Premium
Toward an Understanding of Divergent Compound Eye Development in Drones and Workers of the Honeybee ( Apis mellifera L.): A Correlative Analysis of Morphology and Gene Expression
Author(s) -
Marco Antonio David S.,
Hartfelder Klaus
Publication year - 2016
Publication title -
journal of experimental zoology part b: molecular and developmental evolution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.823
H-Index - 63
eISSN - 1552-5015
pISSN - 1552-5007
DOI - 10.1002/jez.b.22696
Subject(s) - biology , antennal lobe , eye development , retina , drosophila melanogaster , optic nerve , compound eye , gene expression , microarray analysis techniques , microbiology and biotechnology , ommatidium , neuroscience , gene , anatomy , genetics , phenotype , sensory system , optics , physics
Eye development in insects is best understood in Drosophila melanogaster , but little is known for other holometabolous insects. Combining a morphological with a gene expression analysis, we investigated eye development in the honeybee, putting emphasis on the sex‐specific differences in eye size. Optic lobe development starts from an optic lobe anlage in the larval brain, which sequentially gives rise to the lobula, medulla, and lamina. The lamina differentiates in the last larval instar, when it receives optic nerve projections from the developing retina. The expression analysis focused on seven genes important for Drosophila eye development: eyes absent, sine oculis, embryonic lethal abnormal vision, minibrain, small optic lobes, epidermal growth factor receptor , and roughest . All except small optic lob es were more highly expressed in third‐instar drone larvae, but then, in the fourth and fifth instar, their expression was sex‐specifically modulated, showing shifts in temporal dynamics. The clearest differences were seen for small optic lobes , which is highly expressed in the developing eye of workers, and minibrain and roughest , which showed a strong expression peak coinciding with retina differentiation. A microarray analysis for optic lobe/retina complexes revealed the differential expression of several metabolism‐related genes, as well as of two micro‐RNAs. While we could not see major morphological differences in the developing eye structures before the pupal stage, the expression differences observed for the seven candidate genes and in the transcriptional microarray profiles indicate that molecular signatures underlying sex‐specific optic lobe and retina development become established throughout the larval stages.