Regulation of prelamin A endoprotease activity by prelamin A

The maturation of lamin A is completed by the endoproteolytic cleavage of its farnesylated precursor protein, prelamin A, In the absence of this cleavage, prelamin A can neither give rise to lamin A nor assemble into the nuclear lamina, We call the enzyme which catalyzes this endoproteolytic step the 'prelamin A endoprotease'. In this study, we begin characterization of the regulation of prelamin A endoprotease. In particular, we address the question as to whether prelamin A endoprotease activity is constitutive in cells or responds to expression of prelamin A, To do this, me compared the activity of this novel endoprotease in cells which express prelamin A with those that do not, Our data shows that the enzymatic activity of prelamin A endoprotease is enhanced by the expression of prelamin A. (C) 1997 Federation of European Biochemical Societies.