PUBLICATION
A Cytosolic Juxtamembrane Interface Modulates Plexin A3 Oligomerization and Signal Transduction
- Authors
- Barton, R., Palacio, D., Iovine, M.K., Berger, B.W.
- ID
- ZDB-PUB-150108-4
- Date
- 2015
- Source
- PLoS One 10: e0116368 (Journal)
- Registered Authors
- Iovine, M. Kathryn
- Keywords
- none
- MeSH Terms
-
- Amino Acid Sequence
- Animals
- COS Cells
- Cell Adhesion Molecules/antagonists & inhibitors
- Cell Adhesion Molecules/genetics
- Cell Adhesion Molecules/metabolism*
- Cell Membrane/metabolism*
- Chlorocebus aethiops
- Cytosol/metabolism
- Dimerization
- Embryo, Nonmammalian/metabolism
- Humans
- Membrane Proteins/metabolism
- Molecular Sequence Data
- Motor Neurons/metabolism
- Mutagenesis, Site-Directed
- Nerve Tissue Proteins/antagonists & inhibitors
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism*
- Neuropilin-2/metabolism
- Protein Structure, Secondary
- Protein Structure, Tertiary
- Sequence Alignment
- Signal Transduction*
- Zebrafish
- Zebrafish Proteins/antagonists & inhibitors
- Zebrafish Proteins/genetics
- Zebrafish Proteins/metabolism*
- PubMed
- 25565389 Full text @ PLoS One
Citation
Barton, R., Palacio, D., Iovine, M.K., Berger, B.W. (2015) A Cytosolic Juxtamembrane Interface Modulates Plexin A3 Oligomerization and Signal Transduction. PLoS One. 10:e0116368.
Abstract
Plexins (plxns) are transmembrane (TM) receptors involved in the guidance of vascular, lymphatic vessel, and neuron growth as well as cancer metastasis. Plxn signaling results in cytosolic GTPase-activating protein activity, and previous research implicates dimerization as important for activation of plxn signaling. Purified, soluble plxn extracellular and cytosolic domains exhibit only weak homomeric interactions, suggesting a role for the plxn TM and juxtamembrane regions in homooligomerization. In this study, we consider a heptad repeat in the Danio rerio PlxnA3 cytosolic juxtamembrane domain (JM) for its ability to influence PlxnA3 homooligomerization in TM-domain containing constructs. Site-directed mutagenesis in conjunction with the AraTM assay and bioluminescent energy transfer (BRETβ) suggest an interface involving a JM heptad repeat, in particular residue M1281, regulates PlxnA3 homomeric interactions when examined in constructs containing an ectodomain, TM and JM domain. In the presence of a neuropilin-2a co-receptor and semaphorin 3F ligand, disruption to PlxnA3 homodimerization caused by an M1281F mutation is eliminated, suggesting destabilization of the PlxnA3 homodimer in the JM is not sufficient to disrupt co-receptor complex formation. In contrast, enhanced homodimerization of PlxnA3 caused by mutation M1281L remains even in the presence of ligand semaphorin 3F and co-receptor neuropilin-2a. Consistent with this pattern of PlxnA3 dimerization in the presence of ligand and co-receptor, destabilizing mutations to PlxnA3 homodimerization (M1281F) are able to rescue motor patterning defects in sidetracked zebrafish embryos, whereas mutations that enhance PlxnA3 homodimerization (M1281L) are not. Collectively, our results indicate the JM heptad repeat, in particular residue M1281, forms a switchable interface that modulates both PlxnA3 homomeric interactions and signal transduction.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping