Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0043346 (xeroderma pigmentosum)
 2,924 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A protein factor which corrects the defect in xeroderma pigmentosum cells belonging to complementation group A (XP-A cells) was detected in a cell extract prepared from calf thymus. The activity of this factor was measured as the amount of unscheduled DNA synthesis (UDS) reappearing in UV-irradiated XP-A cells after microinjection of the extract. The native molecular mass of this factor was estimated to be 80 kDa by gel-filtration and 25 kDa by glycerol gradient centrifugation. The activity was, however, recovered at a position corresponding to 43 kDa after renaturation on an SDS-PAGE gel. The isoelectric point was determined to be approximately 7.5 by measuring the activity after renaturation on an IEF gel. These values were obtained with a partially purified sample. A spot corresponding to these values was detected on two-dimensional gel electrophoresis with a highly purified sample recovered from an SDS-PAGE gel. The purified protein stimulated UDS specifically in the XP-A cells and endowed the cells with a normal level of UV-resistance. The XP-A cells injected with the factor also showed a normal level of UDS after treatment with either 4HAQO or psoralen plus UV-A. This factor (XP-A complementing factor; XP-ACF) may be involved in the repair of DNA damage induced by various agents.
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PMID:Identification of a specific protein factor defective in group A xeroderma pigmentosum cells. 177 92

Analysis by means of computerized two-dimensional gel electrophoresis (NEPHGE, IEF) of the [35S]-methionine labeled proteins secreted by normal human MRC-5 fibroblasts revealed 476 polypeptides (258 acidic and 218 basic), many of which appeared as charge trains due to modification. Similar analysis of the proteins secreted by SV40 transformed MRC-5 fibroblasts (MRC-5 V2) showed a striking decrease in the levels of many of these proteins as well as the appearance (or increased synthesis) of 47 polypeptides that were either absent or present in very low amounts in normal cells. Of the major secreted polypeptides whose relative proportion decreased dramatically in the MRC-5 V2 cells, 15 were found to be abundant components of other normal (nontransformed) fibroblasts (W138, Xeroderma pigmentosum cell lines). Low levels of these radioactively labeled polypeptides were observed in transformed human cell lines of fibroblast (W138, SV40, HT1080), epithelial (HeLa, transformed amnion cells (AMA), A431, A459) and myeloid (HL-60) origin. No major secreted polypeptide from MRC-5 V2 cells was synthesized exclusively by the transformed cell lines.
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PMID:Secreted proteins from normal and SV40 transformed human MRC-5 fibroblasts: toward establishing a database of human secreted proteins. 282 13