Expression of Robo/Slit and Semaphorin/Plexin/Neuropilin family members in the developing hypothalamic paraventricular and supraoptic nuclei

doi:10.1016/j.gep.2008.06.003

Gene Expression Patterns

Volume 8, Issues 7–8, September 2008, Pages 502-507

https://doi.org/10.1016/j.gep.2008.06.003 Get rights and content

Abstract

The hypothalamic paraventricular nucleus (PVN) and supraoptic nucleus (SON) contain neuroendocrine cells that modulate pituitary secretion to maintain homeostasis. These two nuclei have a common developmental origin but they eventually form at locations distant from each other. Little is known about the molecular cues that direct the segregation of PVN and SON. As a means to identify potential factors, we have documented expression patterns of genes with known guidance roles in neural migration. Here, we focus on two groups of ligand/receptor families classified to mediate chemo-repulsion of neurons and their axons: the Slit/Robo and the Semaphorin/Plexin/Neuropilin families. Their dynamic expression patterns within and around the common PVN/SON progenitor as well as the mature PVN and SON may provide a framework for understanding the formation of these two important nuclei.

Section snippets

Results and discussion

Birth dating experiments in rodents have assigned the origin of the PVN and SON to the anterior ventral lobes of the diencephalon (Altman and Bayer, 1978). They are derived from a common progenitor origin (i.e. the PVN/SON progenitor), but segregate into two distinct nuclei distant from each other. The mature PVN contains both magnocellular (large-body) and parvocellular (small-body) hormone-producing neurons, while the mature SON contains only the magnocellular neurons (Swanson, 1986,

Experimental animals

Mice of BL6/129sv mixed genetic background were used for mating. The vaginal plug date is assigned as E0.5. The anatomical nomenclatures are based on the rat brain atlas by Altman and Bayer (1995). All animal experimentation described herein was conducted in accordance with accepted standards of humane animal care outlined in Ethical Guidelines and approved by IACUC.

In situ hybridization (ISH)

Whole embryo heads were fixed in Methancarn (60% methanol, 30% chloroform, and 10% acetic acid), dehydrated in methanol, embedded

Acknowledgments

We thank Drs. K. Brose, A. Kolodkin, L. Puelles and J. Rubenstein for the plasmids to generate probes for ISH. We also thank Fan lab members for critical readings of the manuscript. This work is supported by National Institutes of Health Grant RO1 HD35596 (to C.M.F.).

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Expression of Robo/Slit and Semaphorin/Plexin/Neuropilin family members in the developing hypothalamic paraventricular and supraoptic nuclei

Abstract

Section snippets

Results and discussion

Experimental animals

In situ hybridization (ISH)

Acknowledgments

Dev. Biol.

Curr. Opin. Cell Biol.

Neurosci. Res.

Brain Res.

Cell

Development of the diencephalon in the rat. II. Correlation of the embryonic development of the hypothalamus with the time of origin of its neurons

J. Comp. Neurol.

Atlas of Prenatal Rat Brain Development

Slit–Robo interactions during cortical development

J. Anat.

Neuropilins as Semaphorin receptors: in vivo functions in neuronal cell migration and axon guidance

Adv. Exp. Med. Biol.

Altered midline axon pathways and ectopic neurons in the developing hypothalamus of netrin-1- and DCC-deficient mice

J. Neurosci.