Psd 95 Protein (Dlg4) is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
PSD-95 (Postsynaptic Density Protein 95), also known as DLG4 (Discs Large Homolog 4), is a pivotal scaffold protein at excitatory synapses in the central nervous system. It is encoded by the DLG4 gene (OMIM: 602887) and serves as a master organizer of the postsynaptic density (PSD), anchoring neurotransmitter receptors, ion channels, and signaling molecules at synaptic sites [1]. PSD-95 is essential for synaptic structure, function, and plasticity, making it a critical player in learning, memory, and synaptic homeostasis. Dysregulation of PSD-95 is implicated in numerous neurodegenerative and neuropsychiatric disorders, including Alzheimer's disease, Parkinson's disease, and autism spectrum disorder [2]. [1]
{| class="infobox infox-protein" [2]
|+ PSD-95 Protein [3]
! colspan="2" | Postsynaptic Density Protein 95 [4]
|- [5]
! Gene [6]
| DLG4 Gene [7]
|- [8]
! UniProt ID [9]
| P78352 [10]
|- [11]
! Molecular Weight [12]
| 95.4 kDa [13]
|- [14]
! Protein Length [15]
| 724 amino acids [16]
|- [17]
! Subcellular Localization [18]
| Postsynaptic density, excitatory synapses [19]
|- [20]
! Protein Family [21]
| MAGUK (Membrane-Associated Guanylate Kinase) family [22]
|- [23]
! Brain Expression [24]
| Highest in cortex, hippocampus, striatum [25]
|- [26]
! PSD Structure [27]
| Core component, ~5% of PSD protein mass [28]
|} [29]
PSD-95 possesses a modular architecture consisting of multiple protein-protein interaction domains: [30]
PSD-95 contains three PDZ (Postsynaptic density-95/Discs Large/Zonula Occludens-1) domains: [31]
The Src Homology 3 domain mediates protein-protein interactions: [32]
The guanylate kinase-like domain: [33]
PSD-95 is the cornerstone of the postsynaptic density: [34]
PSD-95 organizes key signaling pathways: [35]
PSD-95 regulates both LTP (long-term potentiation) and LTD (long-term depression): [36]
PSD-95 alterations are a hallmark of synaptic dysfunction in AD: [37]
| Strategy | Target | Status | Notes | [38]
|----------|--------|--------|-------| [39]
| NMDAR-PSD-95 uncouplers | PDZ domain | Preclinical | NA-1 (Tat-NR2B9c) in trials | [40]
| PSD-95 stabilizers | Protein-protein interactions | Discovery | Protect PSD-95 from degradation | [41]
| Gene therapy | DLG4 expression | Preclinical | AAV delivery approaches | [42]
| Small molecule modulators | PDZ domains | Discovery | Blood-brain barrier penetration challenges | [43]
The most advanced therapeutic application:
The study of Psd 95 Protein (Dlg4) has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
Grant SG (2003) Synapse signalling complexes. Curr Opin Neurobiol 13:120-127. 2003. ↩︎
Kornau HC et al. (1995) Domain interaction between NMDA receptor subunits and PSD-95. 1995. ↩︎
Kim E et al. (1997) GK domain of PSD-95. 1997. ↩︎
Zhu J et al. (2016) PDZ domain binding selectivity. 2016. ↩︎
Saksonen H et al. (2003) SH3 domain function. 2003. ↩︎
Lim IA et al. (2002) SH3 domain interactions in PSD-95. 2002. ↩︎
Stathakis DG et al. (1999) PSD-95 localization mechanisms. 1999. ↩︎
Montgomery JM et al. (2004) GK domain function. 2004. ↩︎
Kim E et al. (1997) GKAP binding to PSD-95. 1997. ↩︎
Scannevin RH & Trimmer JS (2002) MAGUK family in synaptic organization. Trends Neurosci 25:275-277. 2002. ↩︎
Lin Y et al. (2004) PSD-95 anchors NMDA receptors. 2004. ↩︎
Bats C et al. (2007) PSD-95 and AMPA receptor trafficking. 2007. ↩︎
Arnold DB & Clapham DE (1999) Kv1 channel clustering by PSD-95. J Physiol 519:641-654. 1999. ↩︎
Ali MK et al. (2021) PSD-95 and cytoskeleton. 2021. ↩︎
Migaud M et al. (1998) PSD-95 and LTP. 1998. ↩︎
Sattler R et al. (1999) nNOS coupling to PSD-95. 1999. ↩︎
Zhou Q et al. (2008) CaMKII and PSD-95. 2008. ↩︎
Park S et al. (2018) PSD-95 and mTOR signaling. 2018. ↩︎
Mower AF et al. (2002) PSD-95 and memory consolidation. 2002. ↩︎
Wanderoy S et al. (2020) PSD-95 degradation in LTD. 2020. ↩︎
Turrigiano GG (2012) Homeostatic plasticity. Cold Spring Harb Perspect Biol 4:a005306. 2012. ↩︎
Leuba G et al. (2008) PSD-95 in Alzheimer disease. 2008. ↩︎
Manczak M & Reddy PH (2012) Tau and PSD-95 interaction. J Neurochem 123:638-651. 2012. ↩︎
Roselli F et al. (2005) Aβ and PSD-95 delocalization. 2005. ↩︎
Miller CA et al. (2014) GluN2B-PSD-95 in AD. 2014. ↩︎
Hu N et al. (2017) PSD-95 therapeutic strategies in AD. 2017. ↩︎
Villarán RF et al. (2010) PSD-95 in PD substantia nigra. 2010. ↩︎
Garden GA et al. (2002) PSD-95 and dopaminergic function. 2002. ↩︎
Gardoni F et al. (2006) PSD-95 in L-DOPA dyskinesias. 2006. ↩︎
Fogarty MJ et al. (2016) PSD-95 in ALS motor neurons. 2016. ↩︎
Van Damme P et al. (2007) PSD-95 and excitotoxicity in ALS. 2007. ↩︎
Aarts M et al. (2002) NA-1 neuroprotection. 2002. ↩︎
Soriano FX et al. (2008) PSD-95 nNOS inhibition. 2008. ↩︎
Cook DJ et al. (2012) PSD-95 inhibitors for stroke. 2012. ↩︎
Takesue HI et al. (2021) DLG4 variants in autism. 2021. ↩︎
FitzGerald P et al. (2020) DLG4 haploinsufficiency. 2020. ↩︎
Coley AA & Gao WJ (2018) PSD-95 in autism models. Front Cell Neurosci 12:413. 2018. ↩︎
Clinton SM et al. (2003) PSD-95 in schizophrenia. 2003. ↩︎
Bhardwaj SK et al. (2015) PSD-95 and cognitive deficits. 2015. ↩︎
Alam N et al. (2020) Epigenetic regulation of PSD-95. 2020. ↩︎
Cook DJ et al. (2014) NA-1 clinical development. 2014. ↩︎
Hill MD et al. (2022) NA-1 phase 3 trial. 2022. ↩︎
Brouns R et al. (2019) PSD-95 neuroprotection mechanisms. 2019. ↩︎