QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online July 25, 2008
doi: 10.1242/10.1242/dev.019968

This Article Summary Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Eickholt, B. J. Search for Related Content PubMed PubMed Citation Articles by Eickholt, B. J. Social Bookmarking                         What's this?

Functional diversity and mechanisms of action of the semaphorins

MRC Centre for Developmental Neurobiology, King's College London, London SE1 1UL, UK.

View larger version (110K): [in this window] [in a new window]   Fig. 1. Flagging the Sema code. From the left, Hajime Fujisawa and the three meeting organisers Alain Chedotal, Alex Kolodkin and Valerie Castellani in front of the Abbaye des Vaulx de Cernay, where the second EMBO workshop on `Semaphorin function and mechanisms of action' was held. Photo courtesy of B.J.E.

View larger version (27K): [in this window] [in a new window]   Fig. 2. The semaphorin family of proteins. The known members of the semaphorin family have been categorised into 8 classes (V-7). All semaphorins share a 500 amino acid semaphorin (Sema) domain, which is followed, in some classes, by a single Ig-like domain. Several members of the semaphorin family are secreted molecules with no membrane attachment site (for example Class 2 and Class 3 semaphorins), whereas others are linked to the cell surface by a transmembrane domain or by a GPI anchor. One subfamily, the Class 5 semaphorins, contains a set of thrombospondin type I repeats. Adapted, with permission, from the Semaphorin Nomenclature Committee (Semaphorin Nomenclature Committee, 1999).

View larger version (98K): [in this window] [in a new window]   Fig. 3. Semaphorin responses in different neuronal systems. (A) Bath application of embryonic chick dorsal root ganglion (DRG) neurons with Sema3A induces a rapid growth cone collapse response. Picture sequence shows images that were taken 2 minutes before and every 2 minutes after the application of Sema3A at 0 minutes (0'). Image courtesy of B.J.E. (B) Sema3F, expressed in Cos-cells, induces strong repulsion of axons extending from a rat hippocampal explant in a collagen gel assay. Image courtesy of A. Chedotal. (C) Mesodiencephalic dopaminergic (mdDA) neurons in the ventral tegmental area project their axons (green) in the medial forebrain bundle (MFB) rostroventrally through the developing diencephalon and telencephalon to innervate the prefrontal cortex (PFC). Innervation of the PFC is controlled by Class III semaphorins and their neuropilin receptors. Image courtesy of J. Pasterkamp. (D) Growth cones of the medial longitudinal fascicle (MLF) imaged in live transgenic zebrafish embryos. Axons extend normally in tightly bundled fascicles, whereas loss of either Sema3D or Tag1 disrupts fasciculation. Shown here is a morpholino knockdown of Tag1. Image courtesy of M. Halloran. (E) Side view of a neuropilin 1-/- mouse embryo at E12.5 labeled with anti-neurofilament antibody. Loss of neuropilin 1 results in abnormal targetting of efferent projecting neurons. Image courtesy of H. Fujisawa.

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati

Twitter