Does Sc1-70 modulate collagen production in systemic sclerosis?

A Douvas

doi:10.1016/s0140-6736(88)90122-5

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Does Sc1-70 modulate collagen production in systemic sclerosis?

A Douvas

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Abstract

Sc1-70, an autoantigen in systemic sclerosis, may accelerate collagen gene transcription by virtue of its activity as a topoisomerase I (topo I), a DNA template-modifying enzyme. A survey of sequences corresponding to all or part of the known topo I binding sequence AGAACTTAGAGAAAATTTAAA in four fibrillar collagen genes (three of them dermal) and sixteen non-collagen genes showed a striking preponderance of the tetramer 5'-CTTA-3', comprising the core of this binding sequence, at the exon-intron junctions of the fibrillar collagen genes (59% compared with 16% in the control group). In addition, a non-random clustering of three potential topo I binding sites was seen within 350 base-pairs of 5' flanking DNA in the dermal collagen gene alpha 2(I), and a fourth site occurred in the promoter region of the alpha 1(III) gene. The findings suggest that a selective vulnerability to the action of Sc1-70/topo I is built into the structure of the dermal collagen genes.

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Amino Acid Sequence Animals Autoantigens Binding Sites Cartilage Chromosome Mapping Collagen DNA Topoisomerases, Type I Genes Humans Models, Biological Nuclear Proteins Scleroderma, Systemic Skin Transcription, Genetic Journal Article Review

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A Douvas. 1988-08-27. Does Sc1-70 modulate collagen production in systemic sclerosis?. https://doi.org/10.1016/s0140-6736(88)90122-5

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