Development of the embryonic and larval peripheral nervous system of Drosophila

Abstract

The peripheral nervous system (PNS) of embryonic and larval stage Drosophila consists of diverse types of sensory neurons positioned along the body wall. Sensory neurons, and associated end organs, show highly stereotyped locations and morphologies. The many powerful genetic tools for gene manipulation available in Drosophila make the PNS an advantageous system for elucidating basic principles of neural development. Studies of the Drosophila PNS have provided key insights into molecular mechanisms of cell fate specification, asymmetric cell division, and dendritic morphogenesis. A canonical lineage gives rise to sensory neurons and associated organs, and cells within this lineage are diversified through asymmetric cell divisions. Newly specified sensory neurons develop specific dendritic patterns, which are controlled by numerous factors including transcriptional regulators, interactions with neighboring neurons, and intracellular trafficking systems. In addition, sensory axons show modality specific terminations in the central nervous system, which are patterned by secreted ligands and their receptors expressed by sensory axons. Modality-specific axon projections are critical for coordinated larval behaviors. We review the molecular basis for PNS development and address some of the instances in which the mechanisms and molecules identified are conserved in vertebrate development.

Transient localization of the Arp2/3 complex initiates neuronal dendrite branching in vivo

“…To address the specific regulatory events at the core of the process of initial dendrite branch formation, we concentrated on the Drosophila larval sensory da neurons (Gao et al, 1999;Jan and Jan, 2010;Singhania and Grueber, 2014). These fall into four morphologically and functionally distinct neuronal subclasses, which range from the simple cIda to the complex cIIIda and space-filling cIVda neurons (Grueber et al, 2002).…”

Even-Skipped+ Interneurons Are Core Components of a Sensorimotor Circuit that Maintains Left-Right Symmetric Muscle Contraction Amplitude

“…We benefited from prior annotation of many sensory and motor neurons (Ohyama et al, 2015), but we also reconstructed additional sensory and motor neurons to ensure that each sensory neuron class was represented (chordotonal, external sensory, proprioceptors) and each motor neuron class was represented (dorsal-, ventral-, and lateral-projecting motor neurons) (Kohsaka et al, 2012; Singhania and Grueber, 2014). We discovered that multiple proprioceptive sensory neurons – but few or no external sensory or chordotonal neurons – formed direct presynaptic contacts with both local and projection EL interneurons (Figure 7A,B).…”

Growth Factor Signaling Regulates Mechanical Nociception in Flies and Vertebrates

“…Drosophila Type II multidendritic (md) sensory neurons are structurally and functionally similar to vertebrate nociceptors. These neurons have nonmyelinated endings and display elaborate peripheral dendritic projections that contact nearly every larval epidermal cell (Singhania and Grueber, 2014). There are four classes of Type II multidendritic sensory neurons (I-IV) defined by peripheral arbor complexity (Singhania and Grueber, 2014).…”

“…These neurons have nonmyelinated endings and display elaborate peripheral dendritic projections that contact nearly every larval epidermal cell (Singhania and Grueber, 2014). There are four classes of Type II multidendritic sensory neurons (I-IV) defined by peripheral arbor complexity (Singhania and Grueber, 2014). Class III neurons respond to gentle touch (Tsubouchi et al, 2012;Yan et al, 2013), whereas class IV neurons transduce noxious mechanical stimuli (Hwang et al, 2007).…”