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D Van Vactor

Publications and source records attributed to D Van Vactor.

22 records · Page 2Linked to original sources
PubMed1996

The transmembrane tyrosine phosphatase DLAR controls motor axon guidance in Drosophila.

DLAR is a receptor-like, transmembrane protein-tyrosine phosphatase in Drosophila that is expressed almost exclusively by developing neurons. Analysis of Dlar loss-of-function mutations shows that DLAR plays a key role during motoneuron growth cone guidance. Segmental nerve b (SNb) motor axons normally exit the common motor pathway, enter the ventral target region, and then synapse on specific ventral muscles. In Dlar mutant embryos, SNb axons bypass their normal target region and instead continue to extend along the common pathway. SNd motor axons also make pathfinding errors, while SNa and SNc axons appear normal. Thus, DLAR controls the ability of certain motor axons to navigate specific choices points in the developing Drosophila nervous system.

Amino Acid Sequence↗
PubMed1993

From growth cone to synapse: the life history of the RP3 motor neuron.

In Drosophila, the ability to analyze the development of individually identified neurons with a variety of imaging and biophysical techniques can be complemented by sophisticated genetics and molecular biology. This powerful combination is allowing the development and function of single neurons and their synaptic connections to be unraveled at an unparalleled level of resolution. In this article, we focus on a single, identified motoneuron--RP3--arguably the best understood neuron in the fruitfly. Many events in the life history of RP3 are well characterized, including cell migration, axon outgrowth and pathfinding within the central nervous system, pathfinding in the periphery to its appropriate muscle target domain, the specific recognition of its muscle targets, the events of synapse formation and maturation, and its mature function in the locomotion of the fly larva. Genetic analysis has revealed mutations in a number of different genes which affect specific aspects of RP3 development from axon outgrowth to synapse formation.

Animals↗
PubMed1988

Analysis of mutants in chaoptin, a photoreceptor cell-specific glycoprotein in Drosophila, reveals its role in cellular morphogenesis.

Monoclonal antibody 24B10 (MAb24B10) specifically stains photoreceptor neurons in D. melanogaster. It recognizes a 160 kd glycoprotein localized to the extracellular face of the plasma membrane. Using an immunoscreen, we identified two mutations in the encoding gene that cause microvillar disorganization in developing rhabdomeres and disruption of the closely apposed membranes of adjacent cells. In accordance with the mutant phenotype, we have renamed this genetic locus chaoptic and the encoded glycoprotein, chaoptin. Immunoelectron microscopy indicates that chaoptin is distributed along the length of the microvillus. This localization and the morphological abnormalities in mutants support the hypothesis that chaoptin may mediate adhesion between closely apposed membranes. In principle, the immunoscreen utilized here can be used to identify mutations in any gene in Drosophila for which antibodies to the gene product are available.

Animals↗