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Lee SH, Lee HG, Yang EM, Kim CJ. Comparison between transient and permanent congenital hypothyroidism on a thyroid function test after re-evaluation. Ann Pediatr Endocrinol Metab 2023; 28:245-250. [PMID: 38173380 PMCID: PMC10765033 DOI: 10.6065/apem.2244260.130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 01/31/2023] [Accepted: 07/07/2023] [Indexed: 01/05/2024] Open
Abstract
PURPOSE Congenital hypothyroidism (CH) is diagnosed with neonatal screening and is treated early in the neonatal period. Among these patients, transient CH (TCH) is included and requires re-evaluation. The purpose of this study was to find the best way to discontinue levothyroxine and to find trends in thyroid function tests (TFTs) after re-evaluation. METHODS We retrospectively reviewed 388 patients diagnosed with CH. They were classified as permanent CH (PCH) and TCH. The total number of the PCH and TCH groups was 83 (51 boys and 32 girls). We compared clinical parameters to predict TCH and to identify the trends of TFT. RESULTS The first thyroid-stimulating hormone (TSH) value after discontinuation and the average TSH value for 1, 2, and 3 years were all significantly higher in the PCH group (P<0.01). The first fT4 value after discontinuation and the average fT4 value for 1, 2, and 3 years were all significantly higher in the TCH group (P<0.01). The optimal cutoff value on the receiver operating characteristic curve for PCH prediction with an average of 3 years of TSH was greater than 9.05 μIU/mL, which was predicted with a sensitivity of 100% and a specificity of 100%. CONCLUSION When the TSH value ranges from 10 μIU/mL to 20 μIU/mL, clinicians can discontinue levothyroxine if the next result is around 10 μIU/mL or shows a decreasing trend.
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Affiliation(s)
- Song Han Lee
- Department of Pediatrics, Chonnam National University Medical School & Children's Hospital, Gwangju, Korea
| | - Hyun Gyung Lee
- Department of Pediatrics, Chonnam National University Medical School & Children's Hospital, Gwangju, Korea
| | - Eun Mi Yang
- Department of Pediatrics, Chonnam National University Medical School & Children's Hospital, Gwangju, Korea
| | - Chan Jong Kim
- Department of Pediatrics, Chonnam National University Medical School & Children's Hospital, Gwangju, Korea
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2
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Guo Y, Liang X, Li H, Ye M, Zou H, Yu H, Qi T, Hou L, Liang YQ. Effects of norethindrone on the growth, behavior, and thyroid endocrine system of adult female western mosquitofish (Gambusia affinis). ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 267:115630. [PMID: 37890255 DOI: 10.1016/j.ecoenv.2023.115630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 10/20/2023] [Accepted: 10/22/2023] [Indexed: 10/29/2023]
Abstract
Progestins are mainly used in pharmacotherapy and animal husbandry and have received increasing attention as they are widely detected in various aquatic ecosystems. In this study, adult female western mosquitofish (Gambusia affinis) were exposed to different concentrations of norethindrone (NET) (solvent control, 5.0 (L), 50.0 (M), and 500.0 (H) ng/L) for 42 days. Behaviors, morphological parameters, histology of the thyroid, thyroid hormone levels (TSH, T3, and T4), and transcriptional levels of nine genes in the hypothalamic-pituitary-thyroid (HPT) axis were examined. The results showed that NET decreased sociality but increased the anxiety of G. affinis. Sociality makes fish tend to cluster, and anxiety may cause G. affinis to reduce exploration of new environments. Female fish showed hyperplasia, hypertrophy, and glial depletion in their thyroid follicular epithelial cells after NET treatment. The plasma levels of TSH and T4 were significantly reduced, but T3 concentrations were significantly increased in the fish from the H group. In addition, the transcripts of genes (tshb, tshr, tg, dio1, dio2, thrb) in the brains of fish in the M and H treatments were significantly stimulated, while those of trh and pax2a were suppressed. Our results suggest that NET may impact key social behaviors in G. affinis and interfere with the entire thyroid endocrine system, probably via affecting the transcriptional expression of upstream regulators in the HPT axis.
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Affiliation(s)
- Yanfang Guo
- School of Life Sciences, Guangzhou University, Guangzhou 510655, China
| | - Xiaorou Liang
- School of Life Sciences, Guangzhou University, Guangzhou 510655, China
| | - Haisheng Li
- School of Life Sciences, Guangzhou University, Guangzhou 510655, China
| | - Meixin Ye
- School of Life Sciences, Guangzhou University, Guangzhou 510655, China
| | - Hong Zou
- School of Life Sciences, Guangzhou University, Guangzhou 510655, China
| | - Hongjun Yu
- School of Life Sciences, Guangzhou University, Guangzhou 510655, China
| | - Tang Qi
- School of Life Sciences, Guangzhou University, Guangzhou 510655, China
| | - Liping Hou
- School of Life Sciences, Guangzhou University, Guangzhou 510655, China; Key Laboratory of Conservation and Application in Biodiversity of South China, School of Life Sciences, Guangzhou University, Guangzhou, Guangdong 510006, China.
| | - Yan-Qiu Liang
- Faculty of Chemistry and Environmental Science, Guangdong Ocean University, Zhanjiang 524088, China.
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3
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Gomes Pio M, Adrover E, Miras MB, Sobrero G, Molina MF, Scheps KG, Rivolta CM, Targovnik HM. The p.Cys1281Tyr variant in the hinge module/flap region of thyroglobulin causes intracellular transport disorder and congenital hypothyroidism. Mol Cell Endocrinol 2023; 572:111948. [PMID: 37164149 DOI: 10.1016/j.mce.2023.111948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 05/07/2023] [Accepted: 05/08/2023] [Indexed: 05/12/2023]
Abstract
Congenital hypothyroidism (CH) due to thyroglobulin (TG) variants causes very low serum TG levels with normal or enlarged thyroid glands, depending on the severity of the defect, and with autosomal recessive inheritance. The purpose of this study was to functionally characterize p.Cys1281Tyr variant in the TG gene in order to increase our knowledge of the molecular mechanisms associated with CH. In order to find evidence that support the hypothesis that the p.Cys1281Tyr variant would affect the TG folding were performed amino acid prediction, 3D modeling and transient expression analysis in HEK293T cells. 18 of the 21″in silico" algorithms predict a deleterious effect of the p.Cys1281Tyr variant. The full-length 3D model p.Cys1281Tyr TG showed disulfide bond cleavage between the cysteines at positions 1249 and 1281 and rearrangement of the TG structure, while transient expression analysis indicated that p.Cys1281Tyr causes retention of the protein inside the cell. Consequently, these results show that this pathogenic variant makes it impossible for TG to fulfill its function in the biosynthesis process of thyroid hormones, causing CH. In conclusion, our results confirm the pathophysiological importance of misfolding of TG as a consequence of p.Cys1281Tyr variant located in the hinge module/flap region of TG.
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Affiliation(s)
- Mauricio Gomes Pio
- Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires. Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Ezequiela Adrover
- Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires. Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Mirta B Miras
- Servicio de Endocrinología, Hospital de Niños Santísima Trinidad, Córdoba, Argentina
| | - Gabriela Sobrero
- Servicio de Endocrinología, Hospital de Niños Santísima Trinidad, Córdoba, Argentina
| | - Maricel F Molina
- Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires. Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Karen G Scheps
- Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires. Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Carina M Rivolta
- Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires. Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Héctor M Targovnik
- Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires. Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina.
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4
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Jurgens SJ, Choi SH, Morrill VN, Chaffin M, Pirruccello JP, Halford JL, Weng LC, Nauffal V, Roselli C, Hall AW, Oetjens MT, Lagerman B, vanMaanen DP, Aragam KG, Lunetta KL, Haggerty CM, Lubitz SA, Ellinor PT. Analysis of rare genetic variation underlying cardiometabolic diseases and traits among 200,000 individuals in the UK Biobank. Nat Genet 2022; 54:240-250. [PMID: 35177841 PMCID: PMC8930703 DOI: 10.1038/s41588-021-01011-w] [Citation(s) in RCA: 59] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 12/22/2021] [Indexed: 12/30/2022]
Abstract
Cardiometabolic diseases are the leading cause of death worldwide. Despite a known genetic component, our understanding of these diseases remains incomplete. Here, we analyzed the contribution of rare variants to 57 diseases and 26 cardiometabolic traits, using data from 200,337 UK Biobank participants with whole-exome sequencing. We identified 57 gene-based associations, with broad replication of novel signals in Geisinger MyCode. There was a striking risk associated with mutations in known Mendelian disease genes, including MYBPC3, LDLR, GCK, PKD1 and TTN. Many genes showed independent convergence of rare and common variant evidence, including an association between GIGYF1 and type 2 diabetes. We identified several large effect associations for height and 18 unique genes associated with blood lipid or glucose levels. Finally, we found that between 1.0% and 2.4% of participants carried rare potentially pathogenic variants for cardiometabolic disorders. These findings may facilitate studies aimed at therapeutics and screening of these common disorders.
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Affiliation(s)
- Sean J. Jurgens
- Cardiovascular Disease Initiative, The Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Department of Experimental Cardiology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Seung Hoan Choi
- Cardiovascular Disease Initiative, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Valerie N. Morrill
- Cardiovascular Disease Initiative, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Mark Chaffin
- Cardiovascular Disease Initiative, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - James P. Pirruccello
- Cardiovascular Disease Initiative, The Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Cardiovascular Research Center, Massachusetts General Hospital, Boston, MA, USA
| | - Jennifer L. Halford
- Cardiovascular Disease Initiative, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Lu-Chen Weng
- Cardiovascular Disease Initiative, The Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Cardiovascular Research Center, Massachusetts General Hospital, Boston, MA, USA
| | - Victor Nauffal
- Cardiovascular Disease Initiative, The Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Cardiovascular Research Center, Massachusetts General Hospital, Boston, MA, USA
| | - Carolina Roselli
- Cardiovascular Disease Initiative, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Amelia W. Hall
- Cardiovascular Disease Initiative, The Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Cardiovascular Research Center, Massachusetts General Hospital, Boston, MA, USA
| | | | - Braxton Lagerman
- Department of Translational Data Science and Informatics, Geisinger, Danville, PA, USA
| | - David P. vanMaanen
- Department of Translational Data Science and Informatics, Geisinger, Danville, PA, USA
| | | | - Krishna G. Aragam
- Cardiovascular Disease Initiative, The Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Cardiovascular Research Center, Massachusetts General Hospital, Boston, MA, USA
| | - Kathryn L. Lunetta
- NHLBI and Boston University’s Framingham Heart Study, Framingham, MA, USA.,Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA
| | - Christopher M. Haggerty
- Department of Translational Data Science and Informatics, Geisinger, Danville, PA, USA.,Heart Institute, Geisinger, Danville, PA, USA
| | - Steven A. Lubitz
- Cardiovascular Disease Initiative, The Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Cardiovascular Research Center, Massachusetts General Hospital, Boston, MA, USA.,Demoulas Center for Cardiac Arrhythmias, Massachusetts General Hospital, Boston, MA, USA
| | - Patrick T. Ellinor
- Cardiovascular Disease Initiative, The Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Cardiovascular Research Center, Massachusetts General Hospital, Boston, MA, USA.,Demoulas Center for Cardiac Arrhythmias, Massachusetts General Hospital, Boston, MA, USA.,
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5
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Pio MG, Siffo S, Scheps KG, Molina MF, Adrover E, Abelleyro MM, Rivolta CM, Targovnik HM. Curating the gnomAD database: Report of novel variants in the thyrogobulin gene using in silico bioinformatics algorithms. Mol Cell Endocrinol 2021; 534:111359. [PMID: 34119605 DOI: 10.1016/j.mce.2021.111359] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 06/01/2021] [Accepted: 06/02/2021] [Indexed: 01/09/2023]
Abstract
Thyroglobulin (TG) is a large glycosylated protein of 2767 amino acids, secreted by the thyrocytes into the follicular lumen. It plays an essential role in the process of thyroid hormone synthesis. TG gene variants lead to permanent congenital hypothyroidism. In the present work, we report a detailed population and bioinformatic prediction analyses of the TG variants indexed in the Genome Aggregation Database (gnomAD). The results showed a clear predominance of nonsense variants in the European (Finnish), European (Non-Finnish) and Ashkenazi Jewish ethnic groups, whereas the splice site variants predominate in South Asian and African/African-American populations. In total, 282 novel TG variants were described (47 missense involving the wild-type cysteine residues, 177 missense located in the ChEL domain and 58 splice site variants) which were not reported in the literature and that would have deleterious effects in prediction programs. In the gnomAD population, the estimated prevalence of heterozygous carriers of the potentially damaging variants was 1:320. In conclusion, we provide an updated and curated reference source for the diagnosis of thyroid disease, mainly to congenital hypothyroidism due to TG deficiency. The identification and characterization of TG variants is undoubtedly a valuable approach to study the TG structure/function relations and an important tool for clinical diagnosis and genetic counseling.
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Affiliation(s)
- Mauricio Gomes Pio
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Sofia Siffo
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Karen G Scheps
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Maricel F Molina
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Ezequiela Adrover
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Miguel M Abelleyro
- CONICET-Academia Nacional de Medicina, Instituto de Medicina Experimental (IMEX), Buenos Aires, Argentina
| | - Carina M Rivolta
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Héctor M Targovnik
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina.
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6
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Citterio CE, Rivolta CM, Targovnik HM. Structure and genetic variants of thyroglobulin: Pathophysiological implications. Mol Cell Endocrinol 2021; 528:111227. [PMID: 33689781 DOI: 10.1016/j.mce.2021.111227] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 01/22/2021] [Accepted: 02/23/2021] [Indexed: 02/07/2023]
Abstract
Thyroglobulin (TG) plays a main role in the biosynthesis of thyroid hormones (TH), and, thus, it is involved in a wide range of vital functions throughout the life cycle of all vertebrates. Deficiency of TH production due to TG genetic variants causes congenital hypothyroidism (CH), with devastating consequences such as intellectual disability and impaired growth if untreated. To this day, 229 variations in the human TG gene have been identified while the 3D structure of TG has recently appeared. Although TG deficiency is thought to be of autosomal recessive inheritance, the introduction of massive sequencing platforms led to the identification of a variety of monoallelic TG variants (combined with mutations in other thyroid gene products) opening new questions regarding the possibility of oligogenic inheritance of the disease. In this review we discuss remarkable advances in the understanding of the TG architecture and the pathophysiology of CH associated with TG defects, providing new insights for the management of congenital disorders as well as counseling benefits for families with a history of TG abnormalities. Moreover, we summarize relevant aspects of TH synthesis within TG and offer an updated analysis of animal and cellular models of TG deficiency for pathophysiological studies of thyroid dyshormonogenesis while highlighting perspectives for new investigations. All in all, even though there has been sustained progress in understanding the role of TG in thyroid pathophysiology during the past 50 years, functional characterization of TG variants remains an important area of study for future advancement in the field.
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Affiliation(s)
- Cintia E Citterio
- Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires. Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Carina M Rivolta
- Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires. Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Héctor M Targovnik
- Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires. Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina.
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7
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Pio MG, Molina MF, Siffo S, Chiesa A, Rivolta CM, Targovnik HM. A novel mutation in intron 11 donor splice site, responsible of a rare genotype in thyroglobulin gene by altering the pre-mRNA splincing process. Cell expression and bioinformatic analysis. Mol Cell Endocrinol 2021; 522:111124. [PMID: 33321114 DOI: 10.1016/j.mce.2020.111124] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/08/2020] [Accepted: 12/10/2020] [Indexed: 01/09/2023]
Abstract
Thyroglobulin (TG) is a homodimeric glycoprotein synthesized by the thyroid gland. To date, two hundred twenty-seven variations of the TG gene have been identified in humans. Thyroid dyshormonogenesis due to TG gene mutations have an estimated incidence of approximately 1 in 100,000 newborns. The clinical spectrum ranges from euthyroid to mild or severe hypothyroidism. The purpose of the present study was to identify and characterize new variants in the TG gene. We report an Argentine patient with congenital hypothyroidism, enlarged thyroid gland and low levels of serum TG. Sequencing of DNA, expression of chimeric minigenes as well as bioinformatics analysis were performed. DNA sequencing identified the presence of compound heterozygous mutations in the TG gene: the maternal mutation consists of a c.3001+5G > A, whereas the paternal mutation consists of p.Arg296*. Minigen analysis of the variant c.3001+5A performed in HeLa, CV1 and Hek293T cell lines, showed a total lack of transcript expression. So, in order to validate that the loss of expression was caused by such variation, site-directed mutagenesis was performed on the mutated clone, which previously had a pSPL3 vector change, to give rise to a wild-type clone c.3001+5G, endorsing that the mutation c.3001+5G > A is the cause of the total lack of expression. In conclusion, we demonstrate that the c.3001+5G > A mutation causes a rare genotype, altering the splicing of the pre-mRNA. This work contributes to elucidating the molecular bases of TG defects associated with congenital hypothyroidism and expands our knowledge in relation to the pathologic roles of the position 5 in the donor splice site.
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Affiliation(s)
- Mauricio Gomes Pio
- Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires. Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Maricel F Molina
- Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires. Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Sofia Siffo
- Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires. Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Ana Chiesa
- Centro de Investigaciones Endocrinológicas, CEDIE-CONICET, División Endocrinología, Hospital de Niños "Ricardo Gutiérrez", Buenos Aires, Argentina
| | - Carina M Rivolta
- Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires. Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Héctor M Targovnik
- Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires. Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina.
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8
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Citterio CE, Siffo S, Moya CM, Pio MG, Molina MF, Scheps KG, Rey OA, Arvan P, Rivolta CM, Targovnik HM. p.L571P in the linker domain of rat thyroglobulin causes intracellular retention. Mol Cell Endocrinol 2020; 505:110719. [PMID: 31972331 DOI: 10.1016/j.mce.2020.110719] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/14/2020] [Accepted: 01/14/2020] [Indexed: 12/14/2022]
Abstract
Thyroglobulin (TG), a large glycosylated protein secreted by thyrocytes into the thyroid follicular lumen, plays an essential role in thyroid hormone biosynthesis. Rattus norvegicus TG (rTG) is encoded by a large single copy gene, 186-kb long, located on chromosome 7 composed of 48 exons encoding a 8461-kb mRNA. Although the TG gene displays sequence variability, many missense mutations do not impose any adverse effect on the TG protein, whereas other nucleotide substitutions may affect its TG stability and/or TG intracellular trafficking. In order to gain a further understanding of the protein domains regulating its intracellular fate, we cloned a full-length cDNA from rTG into the pcDNA6/V5-His B expression vector. However, transient expression of the cDNA in HEK293T cells showed that the encoded protein was not a wild-type molecule, as it was unable to be secreted in the culture supernatant. Sequencing analyses revealed three random mutations, which accidentally emerged during the course of cloning: c.1712T>C [p.L571P] in the linker domain (amino acid positions 360 to 604), c.2027A>G [p.Q676R] in TG type 1-6 repeat and c.2720A>G [p.Q907R] in the TG type 1-7 repeat. Expression of cDNAs encoding a combination of two mutations [p.Q676R-p.Q907R], [p.L571P-p.Q907R] or [p.L571P-p.Q676R] indicated that any TG bearing the p.L571P substitution was trapped intracellularly. Indeed, we expressed the single point mutant p.L571P and confirmed that this point mutation was sufficient to cause intracellular retention of mutant TG in HEK293T cells. Endo H analysis showed that the p.L571P mutant is completely sensitive to the enzyme, whereas the will-type TG acquires full N-glycan modifications in Golgi apparatus. This data suggest that the p.L571P mutant contains the mannose-type N-glycan, that was added at the first stage of glycosylation. Complex-type N-glycan formation in the Golgi apparatus does not occur, consistent with defective endoplasmic reticulum exit of the mutant TG. Moreover, predictive analysis of the 3D linker domain showed that the p.L571P mutation would result in a significant protein conformational change. In conclusion, our studies identified a novel amino acid residue within the linker domain of TG associated with its conformational maturation and intracellular trafficking.
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Affiliation(s)
- Cintia E Citterio
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Sofia Siffo
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Christian M Moya
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina
| | - Mauricio Gomes Pio
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Maricel F Molina
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Karen G Scheps
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Osvaldo A Rey
- CONICET-Universidad de Buenos Aires, Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Peter Arvan
- Division of Metabolism, Endocrinology & Diabetes, University of Michigan Medical School, Ann Arbor, USA
| | - Carina M Rivolta
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina
| | - Héctor M Targovnik
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética/Cátedra de Genética, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Inmunología, Genética y Metabolismo (INIGEM), Buenos Aires, Argentina.
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