tailieunhanh - Báo cáo khoa học: Identification and characterization of multiple species of tenascin-X in human serum

We analysed the diversity of tenascin-X (TNX) species in serum and studied parameters that could affect determination of TNX levels in serum. Using western blot analysis we identified at least seven distinct TNX species, ran-ging from 75 kDa to the presumably full-length 450 kDa form. | ễFEBS Journal Identification and characterization of multiple species of tenascin-X in human serum D. F. Egging A. C. T. M. Peeters2 N. Grebenchtchikov3 A. Geurts-Moespot3 C. G. J. Sweep M. den Heijer2 and J. Schalkwijk1 1 Department of Dermatology Nijmegen Centre for Molecular Life Sciences Radboud University Nijmegen MedicalCentre the Netherlands 2 Department of Endocrinology Radboud University Nijmegen MedicalCentre the Netherlands 3 Department of ChemicalEndocrinology Radboud University Nijmegen MedicalCentre the Netherlands Keywords collagen Ehlers-Danlos syndrome elastin serum tenascin-X Correspondence J. Schalkwijk Department of Dermatology Nijmegen Centre for Molecular Life Sciences Radboud University Nijmegen MedicalCentre PO Box 9101 6500 HB Nijmegen the Netherlands Fax 31 24 354 1184 Tel 31 24 3613 272 E-mail Received 23 November 2006 revised 21 December 2006 accepted 29 December 2006 doi We analysed the diversity of tenascin-X TNX species in serum and studied parameters that could affect determination of TNX levels in serum. Using western blot analysis we identified at least seven distinct TNX species ranging from 75 kDa to the presumably full-length 450 kDa form. Purification of serum TNX followed by sequence analysis positively identified two major TNX species of 75 and 140 kDa. We found that serum TNX binds to tropoelastin but not to fibrillar collagens. We conclude that serum TNX is composed of distinct molecular species that retain functional activity. Tenascin-X TNX is a large 450 kDa extracellular matrix ECM glycoprotein composed of epidermal growth factor EGF -like repeats fibronectin type III FNIII repeats and a C-terminal fibrinogen domain FbgX 1-4 . A 140 kDa fragment of TNX has been identified in human serum 5 . TNX abnormalities are associated with several pathological conditions 5-9 . Complete TNX deficiency in humans leads to a recessive form of Ehlers-Danlos syndrome EDS and TNX