Camilla Larsen

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Developmental axon pruning is widely used in constructing the nervous system. Accordingly, diverse mechanisms are likely employed for various forms of axon pruning. In the Drosophila mushroom bodies (MB), gamma neurons initially extend axon branches into both the dorsal and medial MB axon lobes in larvae. Through a well-orchestrated set of developmental(More)
In Drosophila embryos, segment boundaries form at the posterior edge of each stripe of engrailed expression. We have used an HRP-CD2 transgene to follow by transmission electron microscopy the cell shape changes that accompany boundary formation. The first change is a loosening of cell contact at the apical side of cells on either side of the incipient(More)
The diencephalon comprises three functionally distinct regions: synencephalon, dorsal thalamus, and ventral thalamus. Patterning of the diencephalon has been proposed to involve subdivision of its anteroposterior axis into segments, neuromeres or prosomeres (Bergquist and Kallen, 1954; Vaage, 1969; Figdor and Stern, 1993; Rubenstein et al., 1994; Redies et(More)
We identified a compartment in the avian prosencephalon, whose cell-lineage-restricted borders enclose about one-third of the early prosencephalic vesicle, defining a region that later narrows to form the zona limitans intrathalamica (zli). Lunatic fringe (L-fng) is expressed in domains flanking the compartment, delineating its anterior and posterior(More)
It is well established that perception is largely multisensory; often served by modalities such as touch, vision, and hearing that detect stimuli emanating from a common point in space; and processed by brain tissue maps that are spatially aligned. However, the neural interactions among modalities that share no spatial stimulus domain yet are essential for(More)
By using a combination of dye injections, clonal labeling, and molecular markers, we have reconstructed the axonal connections between brain and ventral nerve cord of the first-instar Drosophila larva. Out of the approximately 1,400 neurons that form the early larval brain hemisphere, less than 50 cells have axons descending into the ventral nerve cord.(More)
Transposable elements have been used in Drosophila to detect gene expression, inactivate gene function, and induce ectopic expression or overexpression. We have combined all of these features in a single construct. A promoterless GAL4 cDNA is expressed when the construct inserts within a transcriptional unit, and GAL4 activates a GFP-encoding gene present(More)
The Drosophila central brain is composed of approximately 100 paired lineages, with most lineages comprising 100-150 neurons. Most lineages have a number of important characteristics in common. Typically, neurons of a lineage stay together as a coherent cluster and project their axons into a coherent bundle visible from late embryo to adult. Neurons born(More)
Chemotaxis is important for the survival of most animals. How the brain translates sensory input into motor output beyond higher olfactory processing centers is largely unknown. We describe a group of excitatory neurons, termed Odd neurons, which are important for Drosophila larval chemotaxis. Odd neurons receive synaptic input from projection neurons in(More)
Olfactory processing has been intensively studied in Drosophila melanogaster. However, we still know little about the descending neural pathways from the higher order processing centers and how these connect with other neural circuits. Here we describe, in detail, the adult projections patterns that arise from a cluster of 78 neurons, defined by the(More)