N-ethyl-N-Nitrosourea (ENU) induced mutations within the klotho gene lead to ectopic calcification and reduced lifespan in mouse models
Ectopic calcification (EC), which is the pathological deposition of calcium and phosphate in extra-skeletal tissues, may be associated with hypercalcaemic and hyperphosphataemic disorders, or it may occur in the absence of metabolic abnormalities. In addition, EC may be inherited as part of several...
| প্রধান লেখক: | , , , , , , , , , |
|---|---|
| বিন্যাস: | Journal article |
| ভাষা: | English |
| প্রকাশিত: |
Public Library of Science
2015
|
| _version_ | 1826274497278246912 |
|---|---|
| author | Esapa, C Hannan, F Babinsky, V Potter, P Thomas, G Croucher, P Brown, M Brown, S Cox, R Thakker, R |
| author_facet | Esapa, C Hannan, F Babinsky, V Potter, P Thomas, G Croucher, P Brown, M Brown, S Cox, R Thakker, R |
| author_sort | Esapa, C |
| collection | OXFORD |
| description | Ectopic calcification (EC), which is the pathological deposition of calcium and phosphate in extra-skeletal tissues, may be associated with hypercalcaemic and hyperphosphataemic disorders, or it may occur in the absence of metabolic abnormalities. In addition, EC may be inherited as part of several monogenic disorders and studies of these have provided valuable insights into the metabolic pathways regulating mineral metabolism. For example, studies of tumoural calcinosis, a disorder characterised by hyperphosphataemia and progressive EC, have revealed mutations of fibroblast growth factor 23 (<em>FGF23</em>), polypeptide N-acetyl galactosaminyltransferase 3 (<em>GALNT3</em>) and klotho (KL), which are all part of a phosphate-regulating pathway. However, such studies in humans are limited by the lack of available large families with EC, and to facilitate such studies we assessed the progeny of mice treated with the chemical mutagen <em>N</em>-ethyl-<em>N</em>-nitrosourea (ENU) for EC. This identified two mutants with autosomal recessive forms of EC, and reduced lifespan, designated <em>Ecalc1</em> and <em>Ecalc2</em>. Genetic mapping localized the Ecalc1 and Ecalc2 loci to a 11.0 Mb region on chromosome 5 that contained the klotho gene (<em>Kl</em>), and DNA sequence analysis identified nonsense (Gln203Stop) and missense (Ile604Asn) <em>Kl</em> mutations in <em>Ecalc1</em> and <em>Ecalc2</em> mice, respectively. The Gln203Stop mutation, located in KL1 domain, was severely hypomorphic and led to a 17-fold reduction of renal <em>Kl</em> expression. The Ile604Asn mutation, located in KL2 domain, was predicted to impair klotho protein stability and <em>in vitro</em> expression studies in COS-7 cells revealed endoplasmic reticulum retention of the Ile604Asn mutant. Further phenotype studies undertaken in <em>Ecalc1</em> (<em>kl<sup>203X/203X</sup></em>) mice demonstrated elevations in plasma concentrations of phosphate, FGF23 and 1,25-dihydroxyvitamin D. Thus, two allelic variants of <em>Kl</em> that develop EC and represent mouse models for tumoural calcinosis have been established. |
| first_indexed | 2024-03-06T22:44:19Z |
| format | Journal article |
| id | oxford-uuid:5ca1b65f-3530-44eb-a0ba-0f0f9f964ba8 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T22:44:19Z |
| publishDate | 2015 |
| publisher | Public Library of Science |
| record_format | dspace |
| spelling | oxford-uuid:5ca1b65f-3530-44eb-a0ba-0f0f9f964ba82022-03-26T17:29:26ZN-ethyl-N-Nitrosourea (ENU) induced mutations within the klotho gene lead to ectopic calcification and reduced lifespan in mouse modelsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:5ca1b65f-3530-44eb-a0ba-0f0f9f964ba8EnglishORA DepositPublic Library of Science2015Esapa, CHannan, FBabinsky, VPotter, PThomas, GCroucher, PBrown, MBrown, SCox, RThakker, REctopic calcification (EC), which is the pathological deposition of calcium and phosphate in extra-skeletal tissues, may be associated with hypercalcaemic and hyperphosphataemic disorders, or it may occur in the absence of metabolic abnormalities. In addition, EC may be inherited as part of several monogenic disorders and studies of these have provided valuable insights into the metabolic pathways regulating mineral metabolism. For example, studies of tumoural calcinosis, a disorder characterised by hyperphosphataemia and progressive EC, have revealed mutations of fibroblast growth factor 23 (<em>FGF23</em>), polypeptide N-acetyl galactosaminyltransferase 3 (<em>GALNT3</em>) and klotho (KL), which are all part of a phosphate-regulating pathway. However, such studies in humans are limited by the lack of available large families with EC, and to facilitate such studies we assessed the progeny of mice treated with the chemical mutagen <em>N</em>-ethyl-<em>N</em>-nitrosourea (ENU) for EC. This identified two mutants with autosomal recessive forms of EC, and reduced lifespan, designated <em>Ecalc1</em> and <em>Ecalc2</em>. Genetic mapping localized the Ecalc1 and Ecalc2 loci to a 11.0 Mb region on chromosome 5 that contained the klotho gene (<em>Kl</em>), and DNA sequence analysis identified nonsense (Gln203Stop) and missense (Ile604Asn) <em>Kl</em> mutations in <em>Ecalc1</em> and <em>Ecalc2</em> mice, respectively. The Gln203Stop mutation, located in KL1 domain, was severely hypomorphic and led to a 17-fold reduction of renal <em>Kl</em> expression. The Ile604Asn mutation, located in KL2 domain, was predicted to impair klotho protein stability and <em>in vitro</em> expression studies in COS-7 cells revealed endoplasmic reticulum retention of the Ile604Asn mutant. Further phenotype studies undertaken in <em>Ecalc1</em> (<em>kl<sup>203X/203X</sup></em>) mice demonstrated elevations in plasma concentrations of phosphate, FGF23 and 1,25-dihydroxyvitamin D. Thus, two allelic variants of <em>Kl</em> that develop EC and represent mouse models for tumoural calcinosis have been established. |
| spellingShingle | Esapa, C Hannan, F Babinsky, V Potter, P Thomas, G Croucher, P Brown, M Brown, S Cox, R Thakker, R N-ethyl-N-Nitrosourea (ENU) induced mutations within the klotho gene lead to ectopic calcification and reduced lifespan in mouse models |
| title | N-ethyl-N-Nitrosourea (ENU) induced mutations within the klotho gene lead to ectopic calcification and reduced lifespan in mouse models |
| title_full | N-ethyl-N-Nitrosourea (ENU) induced mutations within the klotho gene lead to ectopic calcification and reduced lifespan in mouse models |
| title_fullStr | N-ethyl-N-Nitrosourea (ENU) induced mutations within the klotho gene lead to ectopic calcification and reduced lifespan in mouse models |
| title_full_unstemmed | N-ethyl-N-Nitrosourea (ENU) induced mutations within the klotho gene lead to ectopic calcification and reduced lifespan in mouse models |
| title_short | N-ethyl-N-Nitrosourea (ENU) induced mutations within the klotho gene lead to ectopic calcification and reduced lifespan in mouse models |
| title_sort | n ethyl n nitrosourea enu induced mutations within the klotho gene lead to ectopic calcification and reduced lifespan in mouse models |
| work_keys_str_mv | AT esapac nethylnnitrosoureaenuinducedmutationswithintheklothogeneleadtoectopiccalcificationandreducedlifespaninmousemodels AT hannanf nethylnnitrosoureaenuinducedmutationswithintheklothogeneleadtoectopiccalcificationandreducedlifespaninmousemodels AT babinskyv nethylnnitrosoureaenuinducedmutationswithintheklothogeneleadtoectopiccalcificationandreducedlifespaninmousemodels AT potterp nethylnnitrosoureaenuinducedmutationswithintheklothogeneleadtoectopiccalcificationandreducedlifespaninmousemodels AT thomasg nethylnnitrosoureaenuinducedmutationswithintheklothogeneleadtoectopiccalcificationandreducedlifespaninmousemodels AT croucherp nethylnnitrosoureaenuinducedmutationswithintheklothogeneleadtoectopiccalcificationandreducedlifespaninmousemodels AT brownm nethylnnitrosoureaenuinducedmutationswithintheklothogeneleadtoectopiccalcificationandreducedlifespaninmousemodels AT browns nethylnnitrosoureaenuinducedmutationswithintheklothogeneleadtoectopiccalcificationandreducedlifespaninmousemodels AT coxr nethylnnitrosoureaenuinducedmutationswithintheklothogeneleadtoectopiccalcificationandreducedlifespaninmousemodels AT thakkerr nethylnnitrosoureaenuinducedmutationswithintheklothogeneleadtoectopiccalcificationandreducedlifespaninmousemodels |