Annotated protein:Egl nine homolog 1 (EC 1.14.11.29) (Hypoxia-inducible factor prolyl hydroxylase 2) (HIF-PH2) (HIF-prolyl hydroxylase 2) (HPH-2) (Prolyl hydroxylase domain-containing protein 2) (PHD2) (SM-20). Gene symbol: EGLN1. Taxonomy: Mus musculus (Mouse). Uniprot ID: Q91YE3
antibody wiki:
SynGO gene info:SynGO data @ EGLN1
Ontology domain:Biological Process
SynGO term:regulation of modification of postsynaptic structure (GO:0099159)
Synapse type(s):hippocampus, glutamatergic
Annotated paper:Segura I, et al. "The Oxygen Sensor PHD2 Controls Dendritic Spines and Synapses via Modification of Filamin A" Cell Rep. 2016 Mar 22;14(11):2653-67 PMID:26972007
Figure(s):Fig.3, 5, 6, 7
Annotation description:Complicated story: Egl nine homolog 1; PHD2 is a oxygen sensor that is known to hydroxylate proline residues in target proteins. The E3 ubiquitin ligase von Hippel-Lindau (VHL) is known to ubiquitinate these hydroxylated proteins triggering proteasomal degradation. This paper shows that Egl nine homolog 1; PHD2 is involved in the remodelling of dendritic spines. This remodeling involves proline-hydroxylation of Filamin and its degradation via VHL.

Fig.3: "Phd2 Silencing Impairs Dendritic Spine Maturation"
- "At 14 DIV, Phd2 silencing reduced dendritic protrusion density and the frequency of spines with a head, whereas it increased protrusion length (Figures 3C, 3D, and 3G-3I). Hypoxia did not further alter these parameters in Phd2-silenced MHNs (Figures 3E-3I)...Phd2 silencing also impaired synaptic density, as revealed by the reduced number of vGlut1+/PSD-95+ co-clusters (Figures 3J-3L) and synaptophysin+ clusters (Figures S4M-S4Q)."

Fig.3: "Loss of PHD2 Impairs Dendritic Spine Maturation"
- "Compared with control RFP+ neurons, YFP+ or CFP+ PHD2-deficient cells had reduced protrusion density and increased protrusion length (Figure S4U). Similar results were obtained in MNHs from mice lacking PHD2 in neurons (PHD2NKO) (Figures 3M-3Q; Figure S4V). "
- "Thus, PHD2-mediated hydroxylation is required to induce dendritic spine maturation."

Fig.3: "Phd2 Regulates Dendritic Spine and Synaptic Density In Vivo"
- "Analysis of dendritic spines in the hippocampal CA1 region on postnatal day 15 (P15) revealed that spine density was reduced in shPhd2 neurons in vivo (Figure 3T; Figures S6A and S6B)."

Fig.4:
- "FLNA Is Expressed in Dendritic Filopodia and Spines"
- "FLNA Is Stabilized by Hypoxia, DMOG, or PHD2 Knockdown"

Fig.5:
- "PHD2 Interacts with Domains D21-D23 of FLNA"
- "PHD2 Hydroxylates Proline Residues P2309 and P2316 in FLNA"

Fig.6:
- "VHL Regulates FLNA Protein Levels"
- "VHL Ubiquitinates FLNA"

Fig.7:
- "FLNA Levels Determine Dendritic Spine Morphology"
- "We explored whether Flna silencing reverted the phenotype induced by silencing Phd2. We co-transfected MHNs with tdT together with scr or Flna-specific shRNA (shFlna) alone or together with shPhd2. shFlna reduced FLNA protein levels by 59% ± 8% (n = 3, p < 0.05). Silencing of Flna in MHNs alone increased protrusion length without affecting the protrusion density or the number of spines with a head (Figures 7M-7S). However, in Phd2-silenced MHNs, Flna silencing largely prevented the switch to a more immature spine phenotype (Figures 7M-7S). Thus, FLNA is required for the spine morphology changes induced by PHD2 knockdown."

19/3/2018 Pim
- Since the Egl nine homolog 1; PHD2 protein is a O2 sensor that becomes active upon hypoxia, I have used the 'modification term. Since the effect on actin is not shown but implied I have not annotated to 'modification of the postsynaptic actin cytoskeleton'.
Evidence tracking, Biological System:Intact tissue
Cultured neurons
Evidence tracking, Protein Targeting:Genetic transformation (eg; knockout, knockin, mutations)
RNAi / shRNA
Antibody (detection)
Evidence tracking, Experiment Assay:Confocal
Western blot
Biochemical fractionation (generic)
Annotator(s):Pim van Nierop (ORCID:0000-0003-0593-3443)
Guus Smit (ORCID:0000-0002-2286-1587)
Matthijs Verhage (ORCID:0000-0002-2514-0216)
Lab:Department of Functional Genomics, Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
SynGO annotation ID:2668
Dataset release (version):20231201
View annotation as GO-CAM model:Gene Ontology