Phosphofurin acidic cluster sorting protein 2 (PACS2) plays a vital role in maintaining cellular homeostasis by regulating protein trafficking between cellular membranes. This function impacts crucial processes like apoptosis, mitochondria-endoplasmic reticulum interaction, and subsequently Ca2+ flux, lipid biosynthesis, and autophagy. Missense mutations, particularly E209K and E211K, are linked to developmental and epileptic encephalopathy-66 (DEE66), known as PACS2 syndrome. Individuals with this syndrome exhibit neurodevelopmental delay, seizures, facial dysmorphism, hypotonia, and delayed motor skills.Understanding the impact of these missense mutations on molecular processes is crucial. Studies suggest that E209K mutation decreases phosphorylation, increases the survival time of protein, and modifies protein-protein interaction, consequently leading to disruption of calcium flux and lower resistance to apoptosis induction. Unfortunately, to date, only a limited number of research groups have investigated the effects of mutations in the PACS2 gene. Current research on PACS2 syndrome is hampered by the lack of suitable models. While in vitro models using transfected cell lines offer insights, they cannot fully capture the disease's complexity.To address this, utilizing cells from individuals with PACS2 syndrome, specifically induced pluripotent stem cells (iPSCs), holds promise for understanding phenotypic diversity and developing personalized therapies. However, iPSC models may not fully capture tissue-specific effects of the E209K/E211K mutation. In vivo studies using animal models, particularly mice, could overcome these limitations.This review summarizes current knowledge about PACS2 structure and functions, explores the cellular consequences of E209K and E211K mutations, and highlights the potential of iPSC and mouse models in advancing our understanding of PACS2 syndrome.

Clinical Research Centre Medical University of Bialystok Bialystok Poland

Czech Centre for Phenogenomics Institute of Molecular Genetics of the Czech Academy of Sciences Vestec Czech Republic

Department of Psychiatry Medical University of Bialystok Bialystok Poland

Experimental Medicine Centre Medical University of Bialystok Bialystok Poland

See more in PubMed

Anderson RH, Francis KR (2018) Modeling rare diseases with induced pluripotent stem cell technology. Mol Cell Probes 40:52–59 PubMed DOI PMC

Aslan JE, You H, Williamson DM, Endig J, Youker RT, Thomas L, Shu H, Du Y, Milewski RL, Brush MH, Possemato A, Sprott K, Fu H, Greis KD, Runckel DN, Vogel A, Thomas G (2009) Akt and 14-3-3 control a PACS-2 homeostatic switch that integrates membrane traffic with TRAIL-induced apoptosis. Mol Cell 34:497–509 PubMed DOI PMC

Asth L, Iglesias LP, De Oliveira AC, Moraes MFD, Moreira FA (2021) Exploiting cannabinoid and vanilloid mechanisms for epilepsy treatment. Epilepsy Behav 121:106832 PubMed DOI

Atkins KM, Thomas LL, Barroso-González J, Thomas L, Auclair S, Yin J, Kang H, Chung JH, Dikeakos JD, Thomas G (2014) The multifunctional sorting protein PACS-2 regulates SIRT1-mediated deacetylation of p53 to modulate p21-dependent cell-cycle arrest. Cell Rep 8:1545–1557 PubMed DOI PMC

Barroso-González J, Auclair S, Luan S, Thomas L, Atkins KM, Aslan JE, Thomas LL, Zhao J, Zhao Y, Thomas G (2016) PACS-2 mediates the ATM and NF-κB-dependent induction of anti-apoptotic Bcl-xL in response to DNA damage. Cell Death Differ 23:1448–1457 PubMed DOI PMC

Brinkman BM (2004) Splice variants as cancer biomarkers. Clin Biochem 37:584–594 PubMed DOI

Cesaroni E, Matricardi S, Cappanera S, Marini C (2022) First reported case of an inherited PACS2 pathogenic variant with variable expression. Epileptic Disord 24:572–576 PubMed DOI

Chou IJ, Hou JY, Fan WL, Tsai MH, Lin KL (2023) Long-term outcome of neonatal seizure with. Child (Basel) 10

Dentici ML, Barresi S, Niceta M, Ciolfi A, Trivisano M, Bartuli A, Digilio MC, Specchio N, Dallapiccola B, Tartaglia M (2019) Expanding the clinical spectrum associated with PACS2 mutations. Clin Genet 95:525–531 PubMed DOI

Dombernowsky SL, Samsøe-Petersen J, Petersen CH, Instrell R, Hedegaard AM, Thomas L, Atkins KM, Auclair S, Albrechtsen R, Mygind KJ, Fröhlich C, Howell M, Parker P, Thomas G, Kveiborg M (2015) The sorting protein PACS-2 promotes ErbB signalling by regulating recycling of the metalloproteinase ADAM17. Nat Commun 6:7518 PubMed DOI

Düsterhöft S, Lokau J, Garbers C (2019) The metalloprotease ADAM17 in inflammation and cancer. Pathol Res Pract 215:152410 PubMed DOI

Gerhard DS, Wagner L, Feingold EA, Shenmen CM, Grouse LH, Schuler G, Klein SL, Old S, Rasooly R, Good P, Guyer M, Peck AM, Derge JG, Lipman D, Collins FS, Jang W, Sherry S, Feolo M, Misquitta L, Lee E, Rotmistrovsky K, Greenhut SF, Schaefer CF, Buetow K, Bonner TI, Haussler D, Kent J, Kiekhaus M, Furey T, Brent M, Prange C, Schreiber K, Shapiro N, Bhat NK, Hopkins RF, Hsie F, Driscoll T, Soares MB, Casavant TL, Scheetz TE, Brown-stein MJ, Usdin TB, Toshiyuki S, Carninci P, Piao Y, Dudekula DB, Ko MS, Kawakami K, Suzuki Y, Sugano S, Gruber CE, Smith MR, Simmons B, Moore T, Waterman R, Johnson SL, Ruan Y, Wei CL, Mathavan S, Gunaratne PH, Wu J, Garcia AM, Hulyk SW, Fuh E, Yuan Y, Sneed A, Kowis C, Hodgson A, Muzny DM, McPherson J, Gibbs RA, Fahey J, Helton E, Ketteman M, Madan A, Rodrigues S, Sanchez A, Whiting M, Madari A, Young AC, Wetherby KD, Granite SJ, Kwong PN, Brinkley CP, Pearson RL, Bouffard GG, Blakesly RW, Green ED, Dickson MC, Rodriguez AC, Grimwood J, Schmutz J, Myers RM, Butterfield YS, Griffith M, Griffith OL, Krzywinski MI, Liao N, Morin R, Palmquist D, Petrescu AS, Skalska U, Smailus DE, Stott JM, Schnerch A, Schein JE, Jones SJ, Holt RA, Baross A, Marra MA, Clifton S, Makowski KA, Bosak S, Malek J, Team MP (2004) Genome Res 14:2121–2127 The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC) PubMed DOI

Gubas A, Dikic I (2022) ER remodeling via ER-phagy. Mol Cell 82:1492–1500 PubMed DOI PMC

Hilmi C, Guyot M, Pagès G (2012) VEGF spliced variants: possible role of anti-angiogenesis therapy. J Nucleic Acids 2012, 162692

https://www.uniprot.org

https://www.proteinatlas.org

https://www.pacs2research.org

Hübner CA, Dikic I (2020) ER-phagy and human diseases. Cell Death Differ 27:833–842 PubMed DOI

Ito A, Kawaguchi Y, Lai CH, Kovacs JJ, Higashimoto Y, Appella E, Yao TP (2002) MDM2-HDAC1-mediated deacetylation of p53 is required for its degradation. EMBO J 21:6236–6245 PubMed DOI PMC

Knoell J, Chillappagari S, Knudsen L, Korfei M, Dartsch R, Jonigk D, Kuehnel MP, Hoetzenecker K, Guenther A, Mahavadi P (2022) PACS2-TRPV1 axis is required for ER-mitochondrial tethering during ER stress and lung fibrosis. Cell Mol Life Sci 79:151 PubMed DOI PMC

Köttgen M, Benzing T, Simmen T, Tauber R, Buchholz B, Feliciangeli S, Huber TB, Schermer B, Kramer-Zucker A, Höpker K, Simmen KC, Tschucke CC, Sandford R, Kim E, Thomas G, Walz G (2005) Trafficking of TRPP2 by PACS proteins represents a novel mechanism of ion channel regulation. EMBO J 24:705–716 PubMed DOI PMC

Krzysiak TC, Thomas L, Choi YJ, Auclair S, Qian Y, Luan S, Krasnow SM, Thomas LL, Koharudin LMI, Benos PV, Marks DL, Gronenborn AM, Thomas G (2018) An insulin-responsive sensor in the SIRT1 Disordered Region binds DBC1 and PACS-2 to control enzyme activity. Mol Cell 72:985–998e987 PubMed DOI PMC

Li C, Li L, Yang M, Zeng L, Sun L (2020) PACS-2: a key regulator of mitochondria-associated membranes (MAMs). Pharmacol Res 160:105080 PubMed DOI

Li C, Li L, Yang M, Yang J, Zhao C, Han Y, Zhao H, Jiang N, Wei L, Xiao Y, Liu Y, Xiong X, Xi Y, Luo S, Deng F, Chen W, Yuan S, Zhu X, Xiao L, Sun L (2022) PACS-2 ameliorates tubular Injury by facilitating endoplasmic reticulum-mitochondria contact and Mitophagy in Diabetic Nephropathy. Diabetes 71:1034–1050 PubMed DOI

Li H, Zhang Z, Pan X, Wang Y (2023) New insights into the roles of p53 in Central Nervous System diseases. Int J Neuropsychopharmacol 26:465–473 PubMed DOI PMC

Miranda ER, De Marco L, Soares MM (2009) Splicing variants impact in thyroid normal physiology and pathological conditions. Arq Bras Endocrinol Metabol 53:709–715 PubMed DOI

Mizuno T, Miyata R, Hojo A, Tamura Y, Nakashima M, Mizuguchi T, Matsumoto N, Kato M (2021) Clinical variations of epileptic syndrome associated with PACS2 variant. Brain Dev 43:343–347 PubMed DOI

Myhill N, Lynes EM, Nanji JA, Blagoveshchenskaya AD, Fei H, Carmine Simmen K, Cooper TJ, Thomas G, Simmen T (2008) The subcellular distribution of calnexin is mediated by PACS-2. Mol Biol Cell 19:2777–2788 PubMed DOI PMC

Nagase T, Ishikawa K, Miyajima N, Tanaka A, Kotani H, Nomura N, Ohara O (1998) Prediction of the coding sequences of unidentified human genes. IX. The complete sequences of 100 new cDNA clones from brain which can code for large proteins in vitro. DNA Res 5:31–39 PubMed DOI

Olson HE, Jean-Marçais N, Yang E, Heron D, Tatton-Brown K, van der Zwaag PA, Bijlsma EK, Krock BL, Backer E, Kamsteeg EJ, Sinnema M, Reijnders MRF, Bearden D, Begtrup A, Telegrafi A, Lunsing RJ, Burglen L, Lesca G, Cho MT, Smith LA, Sheidley BR, Achkar ME, Pearl C, Poduri PL, Skraban A, Tarpinian CM, Nesbitt J, Fransen AI, van de Putte DE, Ruivenkamp CAL, Rump P, Chatron N, Sabatier I, De Bellescize J, Guibaud L, Sweetser DA, Waxler JL, Wierenga KJ, Donadieu J, Narayanan V, Ramsey KM, Nava C, Rivière JB, Vitobello A, Tran Mau-Them F, Philippe C, Bruel AL, Duffourd Y, Thomas L, Lelieveld SH, Schuurs-Hoeijmakers J, Brunner HG, Keren B, Thevenon J, Faivre L, Thomas G, Thauvin-Robinet C, Study D, Group CRR (2018) A recurrent De Novo PACS2 heterozygous missense variant causes neonatal-onset Developmental Epileptic Encephalopathy, Facial Dysmorphism, and Cerebellar Dysgenesis. Am J Hum Genet 102:995–1007 PubMed DOI PMC

Pinnapureddy AR, Stayner C, McEwan J, Baddeley O, Forman J, Eccles MR (2015) Large animal models of rare genetic disorders: sheep as phenotypically relevant models of human genetic disease. Orphanet J Rare Dis 10:107 PubMed DOI PMC

Pio R, Montuenga LM (2009) Alternative splicing in lung cancer. J Thorac Oncol 4:674–678 PubMed DOI

Raimondo JV, Burman RJ, Katz AA, Akerman CJ (2015) Ion dynamics during seizures. Front Cell Neurosci 9:419 PubMed DOI PMC

Simmen T, Aslan JE, Blagoveshchenskaya AD, Thomas L, Wan L, Xiang Y, Feliciangeli SF, Hung CH, Crump CM, Thomas G (2005) PACS-2 controls endoplasmic reticulum-mitochondria communication and bid-mediated apoptosis. EMBO J 24:717–729 PubMed DOI PMC

Stoian A, Bajko Z, Bălașa R, Andone S, Stoian M, Ormenișan I, Muntean C, Bănescu C (2024) Characteristics of Developmental and Epileptic Encephalopathy Associated with. Biomolecules 14

Terrone G, Marchese F, Vari MS, Severino M, Madia F, Amadori E, Del Giudice E, Romano A, Gennaro E, Zara F, Striano P (2020) A further contribution to the delineation of epileptic phenotype in PACS2-related syndrome. Seizure 79:53–55 PubMed DOI

Thi My Nhung T, Phuoc Long N, Diem Nghi T, Suh Y, Hoang Anh N, Jung CW, Minh Triet H, Jung M, Woo Y, Yoo J, Noh S, Kim SJ, Lee SB, Park S, Thomas G, Simmen T, Mun J, Rhee HW, Kwon SW, Park SK (2023) Genome-wide kinase-MAM interactome screening reveals the role of CK2A1 in MAM ca. Proc Natl Acad Sci U S A 120:e2303402120 PubMed DOI PMC

Thomas G, Aslan JE, Thomas L, Shinde P, Shinde U, Simmen T (2017) Caught in the act - protein adaptation and the expanding roles of the PACS proteins in tissue homeostasis and disease. J Cell Sci 130:1865–1876 PubMed DOI PMC

Thyagarajan T, Totey S, Danton MJ, Kulkarni AB (2003) Genetically altered mouse models: the good, the bad, and the ugly. Crit Rev Oral Biol Med 14:154–174 PubMed DOI

Tominaga M, Tominaga T (2005) Structure and function of TRPV1. Pflugers Arch 451:143–150 PubMed DOI

Tüshaus J, Sakhteman A, Lechner S, The M, Mucha E, Krisp C, Schlegel J, Delbridge C, Kuster B (2023) A region-resolved proteomic map of the human brain enabled by high-throughput proteomics. EMBO J 42, e114665

Valenzuela I, Guillén Benítez E, Sanchez-Montanez A, Limeres J, López-Grondona F, Cuscó I, Tizzano EF (2022) Vein of Galen aneurysm, dilated cardiomyopathy, and slender habitus in a patient with a recurrent pathogenic variant in PACS2. Am J Med Genet A 188:991–995 PubMed DOI

Wan L, Molloy SS, Thomas L, Liu G, Xiang Y, Rybak SL, Thomas G (1998) PACS-1 defines a novel gene family of cytosolic sorting proteins required for trans-golgi network localization. Cell 94:205–216 PubMed DOI

Wang D, Li Z, Zhang Y, Wang G, Wei M, Hu Y, Ma S, Jiang Y, Che N, Wang X, Yao J, Yin J (2016) Targeting of microRNA-199a-5p protects against pilocarpine-induced status epilepticus and seizure damage via SIRT1-p53 cascade. Epilepsia 57:706–716 PubMed DOI

Werneburg NW, Bronk SF, Guicciardi ME, Thomas L, Dikeakos JD, Thomas G, Gores GJ (2012) Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) protein-induced lysosomal translocation of proapoptotic effectors is mediated by phosphofurin acidic cluster sorting protein-2 (PACS-2). J Biol Chem 287:24427–24437 PubMed DOI PMC

Xue M, Fang T, Sun H, Cheng Y, Li T, Xu C, Tang C, Liu X, Sun B, Chen L (2021) PACS-2 attenuates diabetic kidney disease via the enhancement of mitochondria-associated endoplasmic reticulum membrane formation. Cell Death Dis 12:1107 PubMed DOI PMC

Yamazaki T, Wälchli S, Fujita T, Ryser S, Hoshijima M, Schlegel W, Kuroda S, Maturana AD (2010) Splice variants of enigma homolog, differentially expressed during heart development, promote or prevent hypertrophy. Cardiovasc Res 86:374–382 PubMed DOI PMC

Yang J, Li L, Li C, Chen W, Liu Y, Luo S, Zhao C, Han Y, Yang M, Zhao H, Jiang N, Xi Y, Tang C, Cai J, Xiao L, Liu H, Sun L (2023a) PACS-2 deficiency aggravates tubular injury in diabetic kidney disease by inhibiting ER-phagy. Cell Death Dis 14:649 PubMed DOI PMC

Yang X, Zhuang J, Song W, Shen W, Wu W, Shen H, Han S (2023b) Mitochondria-associated endoplasmic reticulum membrane: overview and inextricable link with cancer. J Cell Mol Med 27:906–919 PubMed DOI PMC

Yu S, Zhang L, Liu C, Yang J, Zhang J, Huang L (2019) PACS2 is required for ox-LDL-induced endothelial cell apoptosis by regulating mitochondria-associated ER membrane formation and mitochondrial ca. Exp Cell Res 379:191–202 PubMed DOI

Zang RX, Mumby MJ, Dikeakos JD (2022) The Phosphofurin Acidic Cluster sorting protein 2 (PACS-2) E209K mutation responsible for PACS-2 syndrome increases susceptibility to apoptosis. ACS Omega 7:34378–34388 PubMed DOI PMC