Semaphorin 3A is a chemoattractant for cortical apical dendrites

  title={Semaphorin 3A is a chemoattractant for cortical apical dendrites},
  author={Franck Polleux and Theresa Morrow and Anirvan Ghosh},
The apical dendrites of pyramidal neurons integrate inputs from various cortical layers and are central to information processing. Here we show that the growth of apical dendrites towards the pial surface is regulated by a diffusible chemoattractant present at high levels near the marginal zone. A major component of this signal is semaphorin 3A (Sema3A), which was previously characterized as a chemorepellant for cortical axons. Soluble guanylate cyclase is asymmetrically localized to the… 

Semaphorin-3A guides radial migration of cortical neurons during development

It is reported that the radial migration of rat layer II/III cortical neurons requires guidance by the extracellular diffusible factor Semaphorin-3A (Sema3A), which is expressed in a descending gradient across the cortical layers, whereas its receptor neuropilin-1 (NP1) is highly expressed in migrating neurons.

Semaphorin 3A induces CaV2.3 channel-dependent conversion of axons to dendrites

Secreted semaphorin 3A (Sema3A) induces the neurite identity of Xenopus spinal commissural interneurons by activating CaV2.3 channels and revealing a mechanism by which a guidance cue controls the identity of neurites during nervous system development.

Semaphorin 5B is a novel inhibitory cue for corticofugal axons.

It is proposed that Semaphorin 5B functions to prevent corticofugal axons from abnormally projecting into germinal regions as they project to their subcortical targets.

Distinct Cytoplasmic Domains in Plexin-A4 Mediate Diverse Responses to Semaphorin 3A in Developing Mammalian Neurons

This study provided insights into the multifunctionality of guidance receptors, in particular showing that the semaphorin 3A signal diverges through specific functions of the modular domains of Plexin-A4 to promote disparate cellular behavior in different neuronal cell types.

Regulation of dendritic development by semaphorin 3A through novel intracellular remote signaling

A control mechanism by which retrograde Sema3A signaling regulates the glutamate receptor localization through trafficking of cis-interacting PlexAs with GluA2 along dendrites may be an alternative mechanism to local adhesive contacts for neural network formation.

Regulation of Dendritic Branching and Spine Maturation by Semaphorin3A-Fyn Signaling

It is shown that Sema3A induces clustering of both postsynaptic density-95 (PSD-95) and presynaptic synapsin I in cultured cortical neurons without changing the density of spines or filopodia, and this suggests that the Sema 3A signaling pathway plays an important role in the regulation of dendritic spine maturation in the cerebral cortex neurons.

Regulation of dendritic length and branching by semaphorin 3A.

It is concluded that Sema3A is necessary for the elaboration of second and third order dendritic branches in pyramidal neurons.



Semaphorins act as attractive and repulsive guidance signals during the development of cortical projections.

The coordinated expression of different semaphorins, together with their specific activities on cortical axons, suggests that multiple guidance signals contribute to the formation of precise corticofugal pathways.

Patterning of cortical efferent projections by semaphorin-neuropilin interactions.

Observations indicate that semaphorin-neuropilin interactions play a critical role in the initial patterning of projections in the developing cortex.

Semaphorin-mediated neuronal growth cone guidance.

Semaphorins III and IV repel hippocampal axons via two distinct receptors.

Chemorepulsion plays a role in axon guidance in the hippocampus, secreted semaphorins are likely to be responsible for this action, and the same axons can be repelled by two distinct semaphoreins via two different receptors.

Differential patterns of semaphorin expression in the developing rat brain

The hypothesis that semaphorins could act as guidance signals in the development of the thalamocortical projections is supported and suggest that innervation specificity is achieved through the combined action of multiple guidance cues.

Many Major CNS Axon Projections Develop Normally in the Absence of Semaphorin III

It is found that many major axonal projections, including climbing fiber, mossy fiber, thalamocortical, and basal forebrain projections and cranial nerves, develop normally in the absence of Sema III, consistent with recent models suggesting that axon guidance is controlled by a balance of forces resulting from multiple guidance cues.

Semaphorin III is needed for normal patterning and growth of nerves, bones and heart

It is shown that in the mutants, some sensory axons project into inappropriate regions of the spinal cord where semaIII is normally expressed, which might serve as a signal that restrains growth in several developing organs.