1
|
Legere EA, Baumholtz AI, Lachance JFB, Archer M, Piontek J, Ryan AK. Claudin-3 in the non-neural ectoderm is essential for neural fold fusion in chicken embryos. Dev Biol 2024; 507:20-33. [PMID: 38154769 DOI: 10.1016/j.ydbio.2023.12.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 12/08/2023] [Accepted: 12/21/2023] [Indexed: 12/30/2023]
Abstract
The neural tube, the embryonic precursor to the brain and spinal cord, begins as a flat sheet of epithelial cells, divided into non-neural and neural ectoderm. Proper neural tube closure requires that the edges of the neural ectoderm, the neural folds, to elevate upwards and fuse along the dorsal midline of the embryo. We have previously shown that members of the claudin protein family are required for the early phases of chick neural tube closure. Claudins are transmembrane proteins, localized in apical tight junctions within epithelial cells where they are essential for regulation of paracellular permeability, strongly involved in apical-basal polarity, cell-cell adhesion, and bridging the tight junction to cytoplasmic proteins. Here we explored the role of Claudin-3 (Cldn3), which is specifically expressed in the non-neural ectoderm. We discovered that depletion of Cldn3 causes folic acid-insensitive primarily spinal neural tube defects due to a failure in neural fold fusion. Apical cell surface morphology of Cldn3-depleted non-neural ectodermal cells exhibited increased membrane blebbing and smaller apical surfaces. Although apical-basal polarity was retained, we observed altered Par3 and Pals1 protein localization patterns within the apical domain of the non-neural ectodermal cells in Cldn3-depleted embryos. Furthermore, F-actin signal was reduced at apical junctions. Our data presents a model of spina bifida, and the role that Cldn3 is playing in regulating essential apical cell processes in the non-neural ectoderm required for neural fold fusion.
Collapse
Affiliation(s)
- Elizabeth-Ann Legere
- Department of Human Genetics, McGill University, Canada; The Research Institute of the McGill University Health Center, Montreal, Quebec, Canada.
| | - Amanda I Baumholtz
- Department of Human Genetics, McGill University, Canada; The Research Institute of the McGill University Health Center, Montreal, Quebec, Canada.
| | | | | | - Jörg Piontek
- Clinical Physiology/Nutritional Medicine, Department of Gastroenterology, Rheumatology and Infectious Diseases, Charité-Universitätsmedizin Berlin, Berlin, Germany.
| | - Aimee K Ryan
- Department of Human Genetics, McGill University, Canada; The Research Institute of the McGill University Health Center, Montreal, Quebec, Canada.
| |
Collapse
|
2
|
Mak S, Hammes A. Canonical and Non-Canonical Localization of Tight Junction Proteins during Early Murine Cranial Development. Int J Mol Sci 2024; 25:1426. [PMID: 38338705 PMCID: PMC10855338 DOI: 10.3390/ijms25031426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 01/12/2024] [Accepted: 01/18/2024] [Indexed: 02/12/2024] Open
Abstract
This study investigates the intricate composition and spatial distribution of tight junction complex proteins during early mouse neurulation. The analyses focused on the cranial neural tube, which gives rise to all head structures. Neurulation brings about significant changes in the neuronal and non-neuronal ectoderm at a cellular and tissue level. During this process, precise coordination of both epithelial integrity and epithelial dynamics is essential for accurate tissue morphogenesis. Tight junctions are pivotal for epithelial integrity, yet their complex composition in this context remains poorly understood. Our examination of various tight junction proteins in the forebrain region of mouse embryos revealed distinct patterns in the neuronal and non-neuronal ectoderm, as well as mesoderm-derived mesenchymal cells. While claudin-4 exhibited exclusive expression in the non-neuronal ectoderm, we demonstrated a neuronal ectoderm specific localization for claudin-12 in the developing cranial neural tube. Claudin-5 was uniquely present in mesenchymal cells. Regarding the subcellular localization, canonical tight junction localization in the apical junctions was predominant for most tight junction complex proteins. ZO-1 (zona occludens protein-1), claudin-1, claudin-4, claudin-12, and occludin were detected at the apical junction. However, claudin-1 and occludin also appeared in basolateral domains. Intriguingly, claudin-3 displayed a non-canonical localization, overlapping with a nuclear lamina marker. These findings highlight the diverse tissue and subcellular distribution of tight junction proteins and emphasize the need for their precise regulation during the dynamic processes of forebrain development. The study can thereby contribute to a better understanding of the role of tight junction complex proteins in forebrain development.
Collapse
Affiliation(s)
- Shermin Mak
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), 13125 Berlin, Germany;
- Institute for Biology, Free University of Berlin, 14159 Berlin, Germany
| | - Annette Hammes
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), 13125 Berlin, Germany;
| |
Collapse
|
3
|
Gelineau-van Waes J, van Waes MA, Hallgren J, Hulen J, Bredehoeft M, Ashley-Koch AE, Krupp D, Gregory SG, Stessman HA. Gene-nutrient interactions that impact magnesium homeostasis increase risk for neural tube defects in mice exposed to dolutegravir. Front Cell Dev Biol 2023; 11:1175917. [PMID: 37377737 PMCID: PMC10292217 DOI: 10.3389/fcell.2023.1175917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 05/19/2023] [Indexed: 06/29/2023] Open
Abstract
In 2018, data from a surveillance study in Botswana evaluating adverse birth outcomes raised concerns that women on antiretroviral therapy (ART) containing dolutegravir (DTG) may be at increased risk for neural tube defects (NTDs). The mechanism of action for DTG involves chelation of Mg2+ ions in the active site of the viral integrase. Plasma Mg2+ homeostasis is maintained primarily through dietary intake and reabsorption in the kidneys. Inadequate dietary Mg2+ intake over several months results in slow depletion of plasma Mg2+ and chronic latent hypomagnesemia, a condition prevalent in women of reproductive age worldwide. Mg2+ is critical for normal embryonic development and neural tube closure. We hypothesized that DTG therapy might slowly deplete plasma Mg2+ and reduce the amount available to the embryo, and that mice with pre-existing hypomagnesemia due to genetic variation and/or dietary Mg2+ insufficiency at the time of conception and initiation of DTG treatment would be at increased risk for NTDs. We used two different approaches to test our hypothesis: 1) we selected mouse strains that had inherently different basal plasma Mg2+ levels and 2) placed mice on diets with different concentrations of Mg2+. Plasma and urine Mg2+ were determined prior to timed mating. Pregnant mice were treated daily with vehicle or DTG beginning on the day of conception and embryos examined for NTDs on gestational day 9.5. Plasma DTG was measured for pharmacokinetic analysis. Our results demonstrate that hypomagnesemia prior to conception, due to genetic variation and/or insufficient dietary Mg2+ intake, increases the risk for NTDs in mice exposed to DTG. We also analyzed whole-exome sequencing data from inbred mouse strains and identified 9 predicted deleterious missense variants in Fam111a that were unique to the LM/Bc strain. Human FAM111A variants are associated with hypomagnesemia and renal Mg2+ wasting. The LM/Bc strain exhibits this same phenotype and was the strain most susceptible to DTG-NTDs. Our results suggest that monitoring plasma Mg2+ levels in patients on ART regimens that include DTG, identifying other risk factors that impact Mg2+ homeostasis, and correcting deficiencies in this micronutrient might provide an effective strategy for mitigating NTD risk.
Collapse
Affiliation(s)
- J. Gelineau-van Waes
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE, United States
| | | | - J. Hallgren
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE, United States
| | - J. Hulen
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE, United States
| | - M. Bredehoeft
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE, United States
| | - A. E. Ashley-Koch
- Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC, United States
| | - D. Krupp
- Department of Medicine, Duke University Medical Center, Durham, NC, United States
| | - S. G. Gregory
- Department of Neurosurgery, Duke University Medical Center, Durham, NC, United States
| | - H. A. Stessman
- Department of Pharmacology and Neuroscience, School of Medicine, Creighton University, Omaha, NE, United States
| |
Collapse
|
4
|
Wu Y, Peng S, Finnell RH, Zheng Y. Organoids as a new model system to study neural tube defects. FASEB J 2021; 35:e21545. [PMID: 33729606 PMCID: PMC9189980 DOI: 10.1096/fj.202002348r] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 02/02/2021] [Accepted: 03/09/2021] [Indexed: 01/09/2023]
Abstract
The neural tube is the first critically important structure that develops in the embryo. It serves as the primordium of the central nervous system; therefore, the proper formation of the neural tube is essential to the developing organism. Neural tube defects (NTDs) are severe congenital defects caused by failed neural tube closure during early embryogenesis. The pathogenesis of NTDs is complicated and still not fully understood even after decades of research. While it is an ethically impossible proposition to investigate the in vivo formation process of the neural tube in human embryos, a newly developed technology involving the creation of neural tube organoids serves as an excellent model system with which to study human neural tube formation and the occurrence of NTDs. Herein we reviewed the recent literature on the process of neural tube formation, the progress of NTDs investigations, and particularly the exciting potential to use neural tube organoids to model the cellular and molecular mechanisms underlying the etiology of NTDs.
Collapse
Affiliation(s)
- Yu Wu
- Department of Cellular and Developmental Biology, School of life sciences, Fudan University, Shanghai, China.,Obstetrics & Gynecology Hospital, The institute of Obstetrics and Gynecology, Fudan University, Shanghai, China
| | - Sisi Peng
- Department of Cellular and Developmental Biology, School of life sciences, Fudan University, Shanghai, China.,Obstetrics & Gynecology Hospital, The institute of Obstetrics and Gynecology, Fudan University, Shanghai, China
| | - Richard H Finnell
- Center for Precision Environmental Health, Departments of Molecular and Cellular Biology, Molecular and Human Genetics and Medicine, Baylor College of Medicine, Houston, TA, USA
| | - Yufang Zheng
- Department of Cellular and Developmental Biology, School of life sciences, Fudan University, Shanghai, China.,Obstetrics & Gynecology Hospital, The institute of Obstetrics and Gynecology, Fudan University, Shanghai, China
| |
Collapse
|