Abstract
cGMP signaling elicited by activation of the transmembrane receptor guanylyl cyclase Npr2 (also known as guanylyl cyclase B) by the ligand CNP controls sensory axon bifurcation of DRG and cranial sensory ganglion (CSG) neurons entering the spinal cord or hindbrain, respectively. Previous studies have shown that Npr2 is phosphorylated on serine and threonine residues in its kinase homology domain (KHD). However, it is unknown whether phosphorylation of Npr2 is essential for axon bifurcation. Here, we generated a knock-in mouse line in which the seven regulatory serine and threonine residues in the KHD of Npr2 were substituted by alanine (Npr2-7A), resulting in a nonphosphorylatable enzyme. Real-time imaging of cGMP in DRG neurons with a genetically encoded fluorescent cGMP sensor or biochemical analysis of guanylyl cyclase activity in brain or lung tissue revealed the absence of CNP-induced cGMP generation in the Npr27A/7A mutant. Consequently, bifurcation of axons, but not collateral formation, from DRG or CSG in this mouse mutant was perturbed at embryonic and mature stages. In contrast, axon branching was normal in a mouse mutant in which constitutive phosphorylation of Npr2 is mimicked by a replacement of all of the seven serine and threonine sites by glutamic acid (Npr2–7E). Furthermore, we demonstrate that the Npr27A/7A mutation causes dwarfism as described for global Npr2 mutants. In conclusion, our in vivo studies provide strong evidence that phosphorylation of the seven serine and threonine residues in the KHD of Npr2 is an important regulatory element of Npr2-mediated cGMP signaling which affects physiological processes, such as axon bifurcation and bone growth.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 9768-9780 |
| Number of pages | 13 |
| Journal | Journal of Neuroscience |
| Volume | 38 |
| Issue number | 45 |
| DOIs | |
| State | Published - Nov 7 2018 |
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Keywords
- Axonal branching
- CGMP signaling
- Npr2
- Phosphorylation
- Sensory axons
Cite this
Regulation of the natriuretic peptide receptor 2 (Npr2) by phosphorylation of juxtamembrane serine and threonine residues is essential for bifurcation of sensory axons. / Schmidt, Hannes; Dickey, Deborah M; Dumoulin, Alexandre; Octave, Marie; Robinson, Jerid W; Kühn, Ralf; Feil, Robert; Potter, Lincoln R; Rathjen, Fritz G.
In: Journal of Neuroscience, Vol. 38, No. 45, 07.11.2018, p. 9768-9780.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Regulation of the natriuretic peptide receptor 2 (Npr2) by phosphorylation of juxtamembrane serine and threonine residues is essential for bifurcation of sensory axons
AU - Schmidt, Hannes
AU - Dickey, Deborah M
AU - Dumoulin, Alexandre
AU - Octave, Marie
AU - Robinson, Jerid W
AU - Kühn, Ralf
AU - Feil, Robert
AU - Potter, Lincoln R
AU - Rathjen, Fritz G.
PY - 2018/11/7
Y1 - 2018/11/7
N2 - cGMP signaling elicited by activation of the transmembrane receptor guanylyl cyclase Npr2 (also known as guanylyl cyclase B) by the ligand CNP controls sensory axon bifurcation of DRG and cranial sensory ganglion (CSG) neurons entering the spinal cord or hindbrain, respectively. Previous studies have shown that Npr2 is phosphorylated on serine and threonine residues in its kinase homology domain (KHD). However, it is unknown whether phosphorylation of Npr2 is essential for axon bifurcation. Here, we generated a knock-in mouse line in which the seven regulatory serine and threonine residues in the KHD of Npr2 were substituted by alanine (Npr2-7A), resulting in a nonphosphorylatable enzyme. Real-time imaging of cGMP in DRG neurons with a genetically encoded fluorescent cGMP sensor or biochemical analysis of guanylyl cyclase activity in brain or lung tissue revealed the absence of CNP-induced cGMP generation in the Npr27A/7A mutant. Consequently, bifurcation of axons, but not collateral formation, from DRG or CSG in this mouse mutant was perturbed at embryonic and mature stages. In contrast, axon branching was normal in a mouse mutant in which constitutive phosphorylation of Npr2 is mimicked by a replacement of all of the seven serine and threonine sites by glutamic acid (Npr2–7E). Furthermore, we demonstrate that the Npr27A/7A mutation causes dwarfism as described for global Npr2 mutants. In conclusion, our in vivo studies provide strong evidence that phosphorylation of the seven serine and threonine residues in the KHD of Npr2 is an important regulatory element of Npr2-mediated cGMP signaling which affects physiological processes, such as axon bifurcation and bone growth.
AB - cGMP signaling elicited by activation of the transmembrane receptor guanylyl cyclase Npr2 (also known as guanylyl cyclase B) by the ligand CNP controls sensory axon bifurcation of DRG and cranial sensory ganglion (CSG) neurons entering the spinal cord or hindbrain, respectively. Previous studies have shown that Npr2 is phosphorylated on serine and threonine residues in its kinase homology domain (KHD). However, it is unknown whether phosphorylation of Npr2 is essential for axon bifurcation. Here, we generated a knock-in mouse line in which the seven regulatory serine and threonine residues in the KHD of Npr2 were substituted by alanine (Npr2-7A), resulting in a nonphosphorylatable enzyme. Real-time imaging of cGMP in DRG neurons with a genetically encoded fluorescent cGMP sensor or biochemical analysis of guanylyl cyclase activity in brain or lung tissue revealed the absence of CNP-induced cGMP generation in the Npr27A/7A mutant. Consequently, bifurcation of axons, but not collateral formation, from DRG or CSG in this mouse mutant was perturbed at embryonic and mature stages. In contrast, axon branching was normal in a mouse mutant in which constitutive phosphorylation of Npr2 is mimicked by a replacement of all of the seven serine and threonine sites by glutamic acid (Npr2–7E). Furthermore, we demonstrate that the Npr27A/7A mutation causes dwarfism as described for global Npr2 mutants. In conclusion, our in vivo studies provide strong evidence that phosphorylation of the seven serine and threonine residues in the KHD of Npr2 is an important regulatory element of Npr2-mediated cGMP signaling which affects physiological processes, such as axon bifurcation and bone growth.
KW - Axonal branching
KW - CGMP signaling
KW - Npr2
KW - Phosphorylation
KW - Sensory axons
UR - http://www.scopus.com/inward/record.url?scp=85056402850&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85056402850&partnerID=8YFLogxK
U2 - 10.1523/JNEUROSCI.0495-18.2018
DO - 10.1523/JNEUROSCI.0495-18.2018
M3 - Article
C2 - 30249793
AN - SCOPUS:85056402850
VL - 38
SP - 9768
EP - 9780
JO - Journal of Neuroscience
JF - Journal of Neuroscience
SN - 0270-6474
IS - 45
ER -