Polycystin-1: immunoaffinity isolation and characterisation by mass spectrometry

Polycystin-1 is a putative 460 kDa membrane protein with a unique structure and is possibly representative of a new family of proteins. Its structure suggests an involvement in cell signalling and cell-matrix interactions. Th e amino acid sequence of polycystin-1 has to date been predicted from its g ene sequence. This, to our knowledge, is the first report of the isolation and analysis of polycystin-1 at the protein level using mass spectrometry t o confirm its predicted structure. The availability of purified polycystin- 1 will allow a new approach to unravelling the complexity of the cell-cell and cell-matrix interactions of this large molecule in normal cells and its perturbation in disease. (C) 2001 Published by Elsevier Science BN. on beh alf of the Federation of European Biochemical Societies.