Aplasia cutis congenita (ACC) is a congenital epidermal defect of the midline scalp and has been proposed to be due to a primary keratinocyte abnormality. Why it forms mainly at this anatomic site has remained a longstanding enigma. KCTD1 mutations cause ACC, ectodermal abnormalities, and kidney fibrosis, whereas KCTD15 mutations cause ACC and cardiac outflow tract abnormalities. Here, we find that KCTD1 and KCTD15 can form multimeric complexes and can compensate for each other's loss, and that disease mutations are dominant-negative, resulting in lack of KCTD1/KCTD15 function. We demonstrate that KCTD15 is critical for cardiac outflow tract development, whereas KCTD1 regulates distal nephron function. Combined inactivation of KCTD1/KCTD15 in keratinocytes results in abnormal skin appendages, but not in ACC. Instead, KCTD1/KCTD15 inactivation in neural crest cells results in ACC linked to midline skull defects, demonstrating that ACC is not caused by a primary defect in keratinocytes but is a secondary consequence of impaired cranial neural crest cells giving rise to midline cranial suture cells that express keratinocyte-promoting growth factors. Our findings explain the clinical observations in patients with KCTD1 versus KCTD15 mutations, establish KCTD1/KCTD15 as critical regulators of ectodermal and neural crest cell functions, and define ACC as a neurocristopathy.
Jackelyn R. Raymundo, Hui Zhang, Giovanni Smaldone, Wenjuan Zhu, Kathleen E. Daly, Benjamin J. Glennon, Giovanni Pecoraro, Marco Salvatore, William A. Devine, Cecilia W. Lo, Luigi Vitagliano, Alexander G. Marneros
Pre-mRNA splicing is a highly coordinated process. While its dysregulation has been linked to neurological deficits, our understanding of the underlying molecular and cellular mechanisms remains limited. We implicated pathogenic variants in U2AF2 and PRPF19, encoding spliceosome subunits in neurodevelopmental disorders (NDDs), by identifying 46 unrelated individuals with 23 de novo U2AF2 missense variants (including seven recurrent variants in 30 individuals) and six individuals with de novo PRPF19 variants. Eight U2AF2 variants dysregulated splicing of a model substrate. Neuritogenesis was reduced in human neurons differentiated from human pluripotent stem cells carrying two U2AF2 hyper-recurrent variants. Neural loss of function of the Drosophila orthologs, U2af50 and Prp19, led to lethality, abnormal mushroom body (MB) patterning, and social deficits, differentially rescued by wild-type and mutant U2AF2 or PRPF19. Transcriptome profiling revealed splicing substrates or effectors (including Rbfox1, a third splicing factor), which rescued MB defects in U2af50 deficient flies. Upon re-analysis of negative clinical exomes followed by data sharing, we further identified six NDD patients carrying RBFOX1 missense variants which, by in vitro testing, showed loss of function. Our study implicates three splicing factors as NDD causative genes and establishes a genetic network with hierarchy underlying human brain development and function.
Dong Li, Qin Wang, Allan Bayat, Mark R. Battig, Yijing Zhou, Daniëlle G.M. Bosch, Gijs van Haaften, Leslie Granger, Andrea K. Petersen, Luis A. Pérez-Jurado, Gemma Aznar-Laín, Anushree Aneja, Miroslava Hancarova, Sarka Bendova, Martin Schwarz, Radka Kremlíková Pourová, Zdenek Sedlacek, Beth A. Keena, Michael E. March, Cuiping Hou, Nora O'Connor, Elizabeth J. Bhoj, Margaret H. Harr, Gabrielle Lemire, Kym M. Boycott, Meghan C. Towne, Megan Li, Mark Tarnopolsky, Lauren Brady, Michael J. Parker, Hanna Faghfoury, Lea Kristin Parsley, Emanuele Agolini, Maria Lisa Dentici, Antonio Novelli, Meredith S. Wright, Rachel Palmquist, Khanh Lai, Marcello Scala, Pasquale Striano, Michele Iacomino, Federico Zara, Annina Cooper, Timothy J. Maarup, Melissa Byler, Robert Roger Lebel, Tugce B. Balci, Raymond J. Louie, Michael J. Lyons, Jessica Douglas, Catherine B. Nowak, Alexandra Afenjar, Juliane Hoyer, Boris Keren, Saskia M. Maas, Mahdi M. Motazacker, Julian A. Martinez-Agosto, Ahna M. Rabani, Elizabeth M. McCormick, Marni Falk, Sarah M. Ruggiero, Ingo Helbig, Rikke S. Møller, Lino Tessarollo, Francesco Tomassoni-Ardori, Mary Ellen Palko, Tzung-Chien Hsieh, Peter M. Krawitz, Mythily Ganapathi, Bruce D. Gelb, Vaidehi Jobanputra, Ashley Wilson, John Greally, Sébastien Jacquemont, Khadijé Jizi, Bruel Ange-Line, Chloé Quelin, Vinod K. Misra, Erika Chick, Corrado Romano, Donatella Greco, Alessia Arena, Manuela Morleo, Vincenzo Nigro, Rie Seyama, Yuri Uchiyama, Naomichi Matsumoto, Ryoji Taira, Katsuya Tashiro, Yasunari Sakai, Gökhan Yigit, Bernd Wollnik, Michael Wagner, Barbara Kutsche, Anna C.E. Hurst, Michelle L. Thompson, Ryan J. Schmidt, Linda M. Randolph, Rebecca C. Spillmann, Vandana Shashi, Edward J. Higginbotham, Dawn Cordeiro, Amanda Carnevale, Gregory Costain, Tayyaba Khan, Benoît Funalot, Frederic Tran Mau-Them, Luis Fernandez Garcia Moya, Sixto García-Miñaúr, Matthew Osmond, Lauren Chad, Nada Quercia, Diana Carrasco, Chumei Li, Amarilis Sanchez-Valle, Meghan Kelley, Mathilde Nizon, Brynjar O. Jensson, Patrick Sulem, Kari Stefansson, Svetlana Gorokhova, Tiffany Busa, Marlène Rio, Hamza Hadj Abdallah, Marion Lesieur-Sebellin, Jeanne Amiel, Véronique Pingault, Sandra Mercier, Marie Vincent, Christophe Philippe, Clemence Fatus-Fauconnier, Kathryn Friend, Rebecca K. Halligan, Sunita Biswas, Jane M.R. Rosser, Cheryl Shoubridge, Mark A. Corbett, Christopher Barnett, Jozef Gecz, Kathleen A. Leppig, Anne Slavotinek, Carlo Marcelis, Rolph Pfundt, Bert B.A. de Vries, Marjon A. van Slegtenhorst, Alice S. Brooks, Benjamin Cogne, Thomas Rambaud, Zeynep Tümer, Elaine H. Zackai, Naiara Akizu, Yuanquan Song, Hakon Hakonarson
Three sisters, born from consanguineous parents, manifested a unique Mullerian anomaly characterized by uterine hypoplasia with thin estrogen-unresponsive endometrium, primary amenorrhea, but spontaneous tubal pregnancies. Through whole-exome sequencing followed by comprehensive genetic analysis, a missense variant was identified in the OSR1 gene. We therefore investigated OSR1/OSR1 expression in postpubertal human uteri, and the prenatal and postnatal expression pattern of Osr1/Osr1 in murine developing Mullerian ducts (MDs) and endometrium, respectively. We then investigated whether Osr1 deletion would affect MD development, using wild-type and genetically engineered mice. Human uterine OSR1/OSR1 expression was found primarily in the endometrium. Mouse Osr1 was expressed prenatally in MDs and Wolffian ducts (WDs), from rostral to caudal segments, in E13.5 embryos. MDs and WDs were absent on the left side and MDs were rostrally truncated on the right side of E13.5 Osr1-/- embryos. Postnatally, Osr1 was expressed in mouse uteri throughout lifespan, peaking at postnatal days 14 and 28. Osr1 protein was present primarily in uterine luminal and glandular epithelial cells and in the epithelial cells of mouse oviducts. Through this translational approach, we demonstrated that OSR1/Osr1 is important for MD development and endometrial receptivity and may be implicated in uterine factor infertility.
Adriana Lofrano-Porto, Sidney Alcântara Pereira, Andrew Dauber, Jordana C.B. Bloom, Audrey N. Fontes, Naomi Asimow, Olívia Laquis de Moraes, Petra Ariadne T. Araujo, Ana Paula Abreu, Michael H. Guo, Silviene F. De Oliveira, Han Liu, Charles Lee, Wendy Kuohung, Michella S. Coelho, Rona S. Carroll, Rulang Jiang, Ursula B. Kaiser
Divya Vinayachandran, Saravana Karthikeyan Balasubramanian
Kara N. Thomas, Destani D. Derrico, Michael C. Golding
Kara N. Thomas, Nimisha Srikanth, Sanat S. Bhadsavle, Kelly R. Thomas, Katherine N. Zimmel, Alison Basel, Alexis N. Roach, Nicole A. Mehta, Yudhishtar S. Bedi, Michael C. Golding
Alice E. Hughes, Elisa De Franco, Rachel M. Freathy, Sarah E. Flanagan, Andrew T. Hattersley
Mutations of G protein coupled receptors (GPCRs) cause various human diseases, but the mechanistic details are limited. Here we establish p.E303K in the gene encoding the endothelin receptor type A (ETAR/EDNRA) as a recurrent mutation causing Mandibulofacial dysostosis with alopecia (MFDA), with craniofacial changes similar to those caused by p.Y129F. Mouse models carrying either of these missense mutations exhibit a partial maxillary-to-mandibular transformation, which is rescued by deleting the ligand endothelin 3 (ET3/EDN3). Pharmacological experiments confirmed the causative ETAR mutations as gain-of-function, dependent on ET3. To elucidate how an amino acid substitution far from the ligand binding site can increase ligand affinity, we used molecular dynamics (MD) simulations. E303 is located at the intracellular end of transmembrane domain 6, and its replacement by a lysine increases flexibility of this portion of the helix, thus favoring G-protein binding and leading to G-protein-mediated enhancement of agonist affinity. The Y129F mutation located under the ligand binding pocket reduces the sodium-water network, thereby affecting the extracellular portion of helices in favor of ET3 binding. These findings provide insight into the pathogenesis of MFDA and into allosteric mechanisms regulating GPCR function, that may provide the basis for drug design targeting GPCRs.
Yukiko Kurihara, Toru Ekimoto, Christopher T. Gordon, Yasunobu Uchijima, Ryo Sugiyama, Taro Kitazawa, Akiyasu Iwase, Risa Kotani, Rieko Asai, Véronique Pingault, Mitsunori Ikeguchi, Jeanne Amiel, Hiroki Kurihara
BACKGROUND. Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies with unpredictable responses to chemotherapy. Approaches to assay patient tumors before treatment and identify effective treatment regimens based on tumor sensitivities are lacking. We developed an organoid-based platform (OBP) to visually quantify patient derived organoid (PDO) responses to drug treatments and associated tumor-stromal modulation for personalized PDAC therapy. METHODS. We retrospectively quantified apoptotic responses and tumor-stromal cell proportions in patient-derived organoids (PDOs) via 3D immunofluorescence imaging through annexin A5, α-smooth muscle actin (α-SMA), and cytokeratin 19 (CK-19) levels. Simultaneously, an ex vivo organoid drug sensitivity assay (ODSA) was used to measure responses to standard of care (SOC) regimens. Differences between ODSA results and patient tumor responses were assessed by exact McNemar test. RESULTS. Immunofluorescent signals, organoid growth curves, and Ki-67 levels were measured and authenticated through the OBP for up to 14 days. ODSA drug responses were not different from patient tumor responses as reflected by CA19-9 reductions following neoadjuvant chemotherapy (P = 0.99). PDOs demonstrated unique apoptotic and tumor-stromal modulation profiles (P < 0.0001). α-SMA/CK-19 ratio levels > 1.0 were associated with improved outcomes (P = 0.0179), and longer parental patient survival by Kaplan-Meier analysis (P = 0.0046). CONCLUSION. Heterogenous apoptotic drug responses and tumor-stromal modulation are present in PDOs after SOC chemotherapy. Ratios of α-SMA and CK-19 levels in PDOs are associated with patient survival and the OBP could aid in the selection of personalized therapies to improve the efficacy of systemic therapy in PDAC patients.
Ya'an Kang, Jenying Deng, Jianhua Ling, Xinqun Li, Yi-Ju Chiang, Eugene J. Koay, Huamin Wang, Jared K. Burks, Paul J. Chiao, Mark W. Hurd, Manoop S. Bhutani, Jeffrey H. Lee, Brian R. Weston, Anirban Maitra, Naruhiko Ikoma, Ching-Wei D. Tzeng, Jeffrey E. Lee, Ronald A. DePinho, Robert A. Wolff, Shubham Pant, Florencia McAllister, Matthew H.G. Katz, Jason B. Fleming, Michael P. Kim
Infantile (fetal and neonatal) megakaryocytes have a distinct phenotype consisting of hyperproliferation, limited morphogenesis, and low platelet production capacity. These properties contribute to clinical problems that include thrombocytopenia in neonates, delayed platelet engraftment in recipients of cord blood stem cell transplants, and inefficient ex vivo platelet production from pluripotent stem cell-derived megakaryocytes. The infantile phenotype results from deficiency of the actin-regulated coactivator, MKL1, which programs cytoskeletal changes driving morphogenesis. As a strategy to complement this molecular defect, we screened pathways with potential to affect MKL1 function and found that Dyrk1a kinase inhibition dramatically enhanced megakaryocyte morphogenesis in vitro and in vivo. Dyrk1 inhibitors rescued enlargement, polyploidization, and thrombopoiesis in human neonatal megakaryocytes. Megakaryocytes derived from induced pluripotent stem cells responded in a similar manner. Progenitors undergoing Dyrk1 inhibition demonstrated filamentous actin assembly, MKL1 nuclear translocation, and modulation of MKL1 target genes. Loss of function studies confirmed MKL1 involvement in this morphogenetic pathway. Ablim2, a stabilizer of filamentous actin, increased with Dyrk1 inhibition, and Ablim2 knockdown abrogated the actin, MKL1, and morphogenetic responses to Dyrk1 inhibition. These results thus delineate a pharmacologically tractable morphogenetic pathway whose manipulation may alleviate clinical problems associated with the limited thrombopoietic capacity of infantile megakaryocytes.
Kamaleldin E. Elagib, Ashton Brock, Cara M. Clementelli, Gohar Mosoyan, Lorrie L. Delehanty, Ranjit K. Sahu, Alexandra Pacheco-Benichou, Corinne Fruit, Thierry Besson, Stephan W. Morris, Koji Eto, Chintan Jobaliya, Deborah L. French, Paul Gadue, Sandeep Singh, Xinrui Shi, Fujun Qin, Robert Cornelison, Hui Li, Camelia Iancu-Rubin, Adam N. Goldfarb
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