Treacher Collins syndrome 3 (TCS3)-associated POLR1C mutants are localized in the lysosome and inhibits chondrogenic differentiation.
Biochem Biophys Res Commun
; 499(1): 78-85, 2018 04 30.
Article
en En
| MEDLINE
| ID: mdl-29567474
ABSTRACT
Treacher Collins syndrome (TCS) is a craniofacial developmental disorder whose key feature is a combination of symptoms. For example, a patient could have bilateral downward slanting of the palpebral fissures, colobomas of the lower eyelids, hypoplasia of the facial bones, cleft palate, malformation of the external ears, and atresia of the external auditory canals. TCS3 is caused by mutations of the polr1c gene, which encodes RNA polymerase I and III subunit C (POLR1C). There have been two known missense mutations (Arg279-to-Gln [R279Q] and Arg279-to-Trp [R279W]) at the Arg-279 position. However, it remains to be clarified whether or how both or each individual mutation affects the cellular properties of POLR1C. Here we show that TCS3-associated missense mutations cause aberrant intracellular localization of POLR1C, inhibiting chondrogenic differentiation. The wild type POLR1C is normally localized in the nuclei. The R279Q or R279W mutant is primarily found to be localized in the lysosome. Expression of the R279Q or R279W mutant in mouse chondrogenic ATDC5 cells decreases phosphorylation of 4E-BP1 and ribosomal S6 proteins, which belong to the mammalian target of rapamycin (mTOR) signaling involved in critical roles in the lysosome. Furthermore, expression of the R279Q or R279W mutant inhibits chondrogenic differentiation in ATDC5 cells. Taken together, TCS3-associated mutation leads to the localization of POLR1C into the lysosome and inhibits chondrogenic differentiation, possibly explaining a portion of the pathological molecular basis underlying Treacher Collins syndrome.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
ARN Polimerasas Dirigidas por ADN
/
Condrocitos
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Condrogénesis
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Disostosis Mandibulofacial
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Mutación
Tipo de estudio:
Risk_factors_studies
Límite:
Animals
/
Humans
Idioma:
En
Revista:
Biochem Biophys Res Commun
Año:
2018
Tipo del documento:
Article
País de afiliación:
Japón