STRUCTURE-FUNCTION STUDIES OF RECOMBINANT MURINE TRIPEPTIDYL-PEPTIDASE-II - THE EXTRA DOMAIN WHICH IS SUBJECT TO ALTERNATIVE SPLICING IS INVOLVED IN COMPLEX-FORMATION

Tripeptidyl-peptidase II (TPP II) is an exopeptidase with a remarkably high native M(r) (>10(6)). Recently, an alternatively spliced, murine cDNA variant was identified which contains an additional 39 bp, encod ing 13 amino acids in the C-terminal end of the protein. The two enzym e variants were expressed in human kidney 293 cells. Both types of sub unit were found to form the active oligomers. In addition, subunits co ntaining the extra 13 amino acids formed an even larger complex elutin g in the void volume of a Sepharose CL-4B column. Thus, it appears tha t this sequence is important for aggregation of subunits. (C) 1997 Fed eration of European Biochemical Societies.