1
|
Bottillo I, D'Alessandro A, Ciccone MP, Cestra G, Di Giacomo G, Silvestri E, Castori M, Brancati F, Lenzi A, Paiardini A, Majore S, Cenci G, Grammatico P. An inherited TBX3 alteration in a prenatal case of ulnar-mammary syndrome: Clinical assessment and functional characterization in Drosophila melanogaster. J Cell Physiol 2024; 239:e31440. [PMID: 39320041 PMCID: PMC11649972 DOI: 10.1002/jcp.31440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 09/03/2024] [Accepted: 09/09/2024] [Indexed: 09/26/2024]
Abstract
Ulnar mammary syndrome (UMS) results from heterozygous variants in the TBX3 gene and impacts limb, tooth, hair, apocrine gland, and genitalia development. The expressivity of UMS is highly variable with no established genotype-phenotype correlations. TBX3 belongs to the Tbx gene family, which encodes transcription factors characterized by the presence of a T-box DNA-binding domain. We describe a fetus exhibiting severe upper limb defects and harboring the novel TBX3:c.400 C > T (p.P134S) variant inherited from the mother who remained clinically misdiagnosed until prenatal diagnosis. Literature revision was conducted to uncover the TBX3 clinical and mutational spectrum. Moreover, we generated a Drosophila humanized model for TBX3 to study the developmental consequences of the p.P134S as well as of other variants targeting different regions of the protein. Phenotypic analysis in flies, coupled with in silico modeling on the TBX3 variants, suggested that the c.400 C > T is UMS-causing and impacts TBX3 localization. Comparative analyses of the fly phenotypes caused by the expression of all variants, demonstrated that missense changes in the T-box domain affect more significantly TBX3 activity than variants outside this domain. To improve the clinicians' recognition of UMS, we estimated the frequency of the main clinical features of the disease. Core features often present pre-pubertally include defects of the ulna and/or of ulnar ray, hypoplastic nipples and/or areolas and, less frequently, genitalia anomalies in young males. These results enhance our understanding of the molecular basis and the clinical spectrum of UMS, shedding light on the functional consequences of TBX3 variants in a developmental context.
Collapse
Affiliation(s)
- Irene Bottillo
- Division of Medical Genetics, Department of Experimental Medicine, San Camillo‐Forlanini HospitalSapienza UniversityRomeItaly
| | - Andrea D'Alessandro
- Department of Biology and Biotechnologies “C. Darwin”Sapienza University of RomeRomeItaly
- Istituto Pasteur Italia‐Fondazione Cenci BolognettiRomeItaly
| | - Maria Pia Ciccone
- Division of Medical Genetics, Department of Experimental Medicine, San Camillo‐Forlanini HospitalSapienza UniversityRomeItaly
| | - Gianluca Cestra
- Department of Biology and Biotechnologies “C. Darwin”Sapienza University of RomeRomeItaly
- Institute of Molecular Biology and Pathology (IBPM), National Research Council (CNR)RomeItaly
- Fondazione Santa Lucia IRCCS, c/o CERCRomeItaly
| | - Gianluca Di Giacomo
- Division of Medical Genetics, Department of Experimental Medicine, San Camillo‐Forlanini HospitalSapienza UniversityRomeItaly
| | - Evelina Silvestri
- Unit of Fetal and Neonatal Pathology, Division of PathologySan Camillo‐Forlanini HospitalRomeItaly
| | - Marco Castori
- Division of Medical GeneticsFondazione IRCCS‐Casa Sollievo della SofferenzaSan Giovanni RotondoItaly
| | - Francesco Brancati
- Human Genetics Laboratory, Department of Life, Health and Environmental SciencesUniversity of L'AquilaItaly
- San Raffaele Roma IRCCSRomeItaly
| | - Andrea Lenzi
- Department of Experimental MedicineSapienza University of RomeRomeItaly
| | - Alessandro Paiardini
- Department of Biochemical Sciences “A. Rossi Fanelli”Sapienza University of RomeRomeItaly
| | - Silvia Majore
- Division of Medical Genetics, Department of Experimental Medicine, San Camillo‐Forlanini HospitalSapienza UniversityRomeItaly
| | - Giovanni Cenci
- Department of Biology and Biotechnologies “C. Darwin”Sapienza University of RomeRomeItaly
- Istituto Pasteur Italia‐Fondazione Cenci BolognettiRomeItaly
| | - Paola Grammatico
- Division of Medical Genetics, Department of Experimental Medicine, San Camillo‐Forlanini HospitalSapienza UniversityRomeItaly
| |
Collapse
|
2
|
Wehn AK, Farkas DR, Sedlock CE, Subedi D, Chapman DL. Functionally distinct roles for T and Tbx6 during mouse development. Biol Open 2020; 9:9/8/bio054692. [PMID: 32855167 PMCID: PMC7473639 DOI: 10.1242/bio.054692] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The mouse T-box transcription factors T and Tbx6 are co-expressed in the primitive streak and have unique domains of expression; T is expressed in the notochord, while Tbx6 is expressed in the presomitic mesoderm. T-box factors are related through a shared DNA binding domain, the T-domain, and can therefore bind to similar DNA sequences at least in vitro. We investigated the functional similarities and differences of T and Tbx6 DNA binding and transcriptional activity in vitro and their interaction genetically in vivo. We show that at one target, Dll1, the T-domains of T and Tbx6 have different affinities for the binding sites present in the mesoderm enhancer. We further show using in vitro assays that T and Tbx6 differentially affect transcription with Tbx6 activating expression tenfold higher than T, that T and Tbx6 can compete at target gene enhancers, and that this competition requires a functional DNA binding domain. Next, we addressed whether T and Tbx6 can compete in vivo. First, we generated embryos that express Tbx6 at greater than wild-type levels embryos and show that these embryos have short tails, resembling the T heterozygous phenotype. Next, using the dominant-negative TWis allele, we show that Tbx6+/− TWis/+ embryos share similarities with embryos homozygous for the Tbx6 hypomorphic allele rib-vertebrae, specifically fusions of several ribs and malformation of some vertebrae. Finally, we tested whether Tbx6 can functionally replace T using a knockin approach, which resulted in severe T null-like phenotypes in chimeric embryos generated with ES cells heterozygous for a Tbx6 knockin at the T locus. Altogether, our results of differences in affinity for DNA binding sites and transcriptional activity for T and Tbx6 provide a potential mechanism for the failure of Tbx6 to functionally replace T and possible competition phenotypes in vivo. Summary: Mouse Tbx6 fails to compensate for heterozygous loss of T; instead ectopic Tbx6 in the T expression-domain in knockin embryos generates T null-like phenotypes suggestive of competition.
Collapse
Affiliation(s)
- Amy K Wehn
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Deborah R Farkas
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Carly E Sedlock
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Dibya Subedi
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Deborah L Chapman
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| |
Collapse
|
3
|
Reinhardt S, Schuck F, Stoye N, Hartmann T, Grimm MOW, Pflugfelder G, Endres K. Transcriptional repression of the ectodomain sheddase ADAM10 by TBX2 and potential implication for Alzheimer's disease. Cell Mol Life Sci 2019; 76:1005-1025. [PMID: 30599067 PMCID: PMC11105458 DOI: 10.1007/s00018-018-2998-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 12/11/2018] [Accepted: 12/12/2018] [Indexed: 12/15/2022]
Abstract
BACKGROUND The ADAM10-mediated cleavage of transmembrane proteins regulates cellular processes such as proliferation or migration. Substrate cleavage by ADAM10 has also been implicated in pathological situations such as cancer or Morbus Alzheimer. Therefore, identifying endogenous molecules, which modulate the amount and consequently the activity of ADAM10, might contribute to a deeper understanding of the enzyme's role in both, physiology and pathology. METHOD To elucidate the underlying cellular mechanism of the TBX2-mediated repression of ADAM10 gene expression, we performed overexpression, RNAi-mediated knockdown and pharmacological inhibition studies in the human neuroblastoma cell line SH-SY5Y. Expression analysis was conducted by e.g. real-time RT-PCR or western blot techniques. To identify the binding region of TBX2 within the ADAM10 promoter, we used luciferase reporter assay on deletion constructs and EMSA/WEMSA experiments. In addition, we analyzed a TBX2 loss-of-function Drosophila model regarding the expression of ADAM10 orthologs by qPCR. Furthermore, we quantified the mRNA level of TBX2 in post-mortem brain tissue of AD patients. RESULTS Here, we report TBX2 as a transcriptional repressor of ADAM10 gene expression: both, the DNA-binding domain and the repression domain of TBX2 were necessary to effect transcriptional repression of ADAM10 in neuronal SH-SY5Y cells. This regulatory mechanism required HDAC1 as a co-factor of TBX2. Transcriptional repression was mediated by two functional TBX2 binding sites within the core promoter sequence (- 315 to - 286 bp). Analysis of a TBX2 loss-of-function Drosophila model revealed that kuzbanian and kuzbanian-like, orthologs of ADAM10, were derepressed compared to wild type. Vice versa, analysis of cortical brain samples of AD-patients, which showed reduced ADAM10 mRNA levels, revealed a 2.5-fold elevation of TBX2, while TBX3 and TBX21 levels were not affected. CONCLUSION Our results characterize TBX2 as a repressor of ADAM10 gene expression and suggest that this regulatory interaction is conserved across tissues and species.
Collapse
Affiliation(s)
- Sven Reinhardt
- Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg University Mainz, Untere Zahlbacher Strasse 8, 55131, Mainz, Germany
| | - Florian Schuck
- Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg University Mainz, Untere Zahlbacher Strasse 8, 55131, Mainz, Germany
| | - Nicolai Stoye
- Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg University Mainz, Untere Zahlbacher Strasse 8, 55131, Mainz, Germany
| | - Tobias Hartmann
- Deutsches Institut für Demenz Prävention (DIDP), Neurodegeneration and Neurobiology, Saarland University, Kirrbergerstrasse 1, 66421, Homburg, Saar, Germany
- Experimental Neurology, Saarland University, Kirrbergerstrasse 1, 66421, Homburg, Saar, Germany
| | - Marcus O W Grimm
- Deutsches Institut für Demenz Prävention (DIDP), Neurodegeneration and Neurobiology, Saarland University, Kirrbergerstrasse 1, 66421, Homburg, Saar, Germany
- Experimental Neurology, Saarland University, Kirrbergerstrasse 1, 66421, Homburg, Saar, Germany
| | - Gert Pflugfelder
- Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University, Becherweg 32, 55128, Mainz, Germany
| | - Kristina Endres
- Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg University Mainz, Untere Zahlbacher Strasse 8, 55131, Mainz, Germany.
| |
Collapse
|
4
|
Fischer K, Pflugfelder GO. Putative Breast Cancer Driver Mutations in TBX3 Cause Impaired Transcriptional Repression. Front Oncol 2015; 5:244. [PMID: 26579496 PMCID: PMC4625211 DOI: 10.3389/fonc.2015.00244] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 10/14/2015] [Indexed: 12/17/2022] Open
Abstract
The closely related T-box transcription factors TBX2 and TBX3 are frequently overexpressed in melanoma and various types of human cancers, in particular, breast cancer. The overexpression of TBX2 and TBX3 can have several cellular effects, among them suppression of senescence, promotion of epithelial-mesenchymal transition, and invasive cell motility. In contrast, loss of function of TBX3 and most other human T-box genes causes developmental haploinsufficiency syndromes. Stephens and colleagues (1), by exome sequencing of breast tumor samples, identified five different mutations in TBX3, all affecting the DNA-binding T-domain. One in-frame deletion of a single amino acid, p.N212delN, was observed twice. Due to the clustering of these mutations to the T-domain and for statistical reasons, TBX3 was inferred to be a driver gene in breast cancer. Since mutations in the T-domain generally cause loss of function and because the tumorigenic action of TBX3 has generally been attributed to overexpression, we determined whether the putative driver mutations had loss- or gain-of-function properties. We tested two in-frame deletions, one missense, and one frameshift mutant protein for DNA-binding in vitro, and for target gene repression in cell culture. In addition, we performed an in silico analysis of somatic TBX mutations in breast cancer, collected in The Cancer Genome Atlas (TCGA). Both the experimental and the in silico analysis indicate that the observed mutations predominantly cause loss of TBX3 function.
Collapse
|
5
|
Tsai YC, Grimm S, Chao JL, Wang SC, Hofmeyer K, Shen J, Eichinger F, Michalopoulou T, Yao CK, Chang CH, Lin SH, Sun YH, Pflugfelder GO. Optomotor-blind negatively regulates Drosophila eye development by blocking Jak/STAT signaling. PLoS One 2015; 10:e0120236. [PMID: 25781970 PMCID: PMC4363906 DOI: 10.1371/journal.pone.0120236] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 01/27/2015] [Indexed: 12/23/2022] Open
Abstract
Organ formation requires a delicate balance of positive and negative regulators. In Drosophila eye development, wingless (wg) is expressed at the lateral margins of the eye disc and serves to block retinal development. The T-box gene optomotor-blind (omb) is expressed in a similar pattern and is regulated by Wg. Omb mediates part of Wg activity in blocking eye development. Omb exerts its function primarily by blocking cell proliferation. These effects occur predominantly in the ventral margin. Our results suggest that the primary effect of Omb is the blocking of Jak/STAT signaling by repressing transcription of upd which encodes the Jak receptor ligand Unpaired.
Collapse
Affiliation(s)
- Yu-Chen Tsai
- Institute of Genetics, National Yang-Ming University, Taipei; Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, Republic of China
- Department of Life Science and Life Science Center, Tunghai University, Taichung, Taiwan, Republic of China
| | - Stefan Grimm
- Theodor-Boveri-Institut, Biozentrum, Lehrstuhl für Genetik und Neurobiologie, Universität Würzburg, Am Hubland, Würzburg, Germany
| | - Ju-Lan Chao
- Institute of Genetics, National Yang-Ming University, Taipei; Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, Republic of China
| | - Shih-Chin Wang
- Department of Life Science and Life Science Center, Tunghai University, Taichung, Taiwan, Republic of China
| | - Kerstin Hofmeyer
- Theodor-Boveri-Institut, Biozentrum, Lehrstuhl für Genetik und Neurobiologie, Universität Würzburg, Am Hubland, Würzburg, Germany
| | - Jie Shen
- Institut für Genetik, Universität Mainz, Mainz, Germany
- Department of Entomology, China Agricultural University, Beijing, China
| | | | | | - Chi-Kuang Yao
- Institute of Genetics, National Yang-Ming University, Taipei; Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, Republic of China
| | - Chih-Hsuan Chang
- Department of Life Science and Life Science Center, Tunghai University, Taichung, Taiwan, Republic of China
| | - Shih-Han Lin
- Department of Life Science and Life Science Center, Tunghai University, Taichung, Taiwan, Republic of China
| | - Y. Henry Sun
- Institute of Genetics, National Yang-Ming University, Taipei; Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, Republic of China
- * E-mail: (YHS); (GOP)
| | - Gert O. Pflugfelder
- Theodor-Boveri-Institut, Biozentrum, Lehrstuhl für Genetik und Neurobiologie, Universität Würzburg, Am Hubland, Würzburg, Germany
- Institut für Genetik, Universität Mainz, Mainz, Germany
- * E-mail: (YHS); (GOP)
| |
Collapse
|