A genetic defect in the biosynthesis of dermatan sulfate proteoglycan: galactosyltransferase I deficiency in fibroblasts from a patient with a progeroid syndrome.
Proc Natl Acad Sci U S A
; 87(4): 1342-6, 1990 Feb.
Article
en En
| MEDLINE
| ID: mdl-2106134
ABSTRACT
A small proteoglycan that contains only a single dermatan sulfate chain is the main proteoglycan synthesized by skin fibroblasts. Fibroblasts from a patient with progeroidal appearance and symptoms of the Ehlers-Danlos syndrome have a reduced ability of converting the core protein of this proteoglycan into a mature glycosaminoglycan chain-bearing species. This abnormality is the consequence of a deficiency in galactosyltransferase I (xylosylprotein 4-beta-galactosyltransferase; EC 2.4.1.133), which catalyzes the second glycosyl transfer reaction in the assembly of the dermatan sulfate chain. The glycosaminoglycan-free core protein secreted by the patient's fibroblasts bears an unsubstituted xylose residue. The mutant enzyme is abnormally thermolabile. Preincubation of fibroblasts at 41 degrees C leads to a further reduction in the production of mature proteoglycan and affects the capacity for glycosaminoglycan synthesis on p-nitrophenyl beta-D-xyloside more strongly in the mutant than in control cells.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Progeria
/
Proteoglicanos Tipo Condroitín Sulfato
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Proteoglicanos
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Condroitín
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Dermatán Sulfato
Límite:
Female
/
Humans
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Male
Idioma:
En
Año:
1990
Tipo del documento:
Article