Expression and characterization of constitutively active human caspase-14

Biochem Biophys Res Commun. 2006 Sep 8;347(4):941-8. doi: 10.1016/j.bbrc.2006.06.156. Epub 2006 Jul 10.


Caspase-14 is a cysteine endoproteinase that is expressed in the epidermis and a limited number of other tissues. It is activated during keratinocyte differentiation by zymogen processing, but its precise function is unknown. To obtain caspase-14 for functional studies, we engineered and expressed a constitutively active form of human caspase-14 (Rev-hC14) in Escherichia coli and cultured mammalian cells. Rev-hC14 required no proteolytic processing for activity, showed strong activity against the caspase substrate WEHD, and was inhibited by the pan-caspase inhibitor zVAD-fmk. Mammalian cells that expressed active caspase-14 showed normal cell adherence and morphology. Using positional scanning of synthetic tetrapeptide libraries, we determined the substrate preference of human caspase-14 to be W (or Y)-X-X-D. These studies affirm that caspase-14 has a substrate specificity similar to the group I caspases, and demonstrate that it functions in a distinct manner from executioner caspases to carry out specific proteolytic events during keratinocyte differentiation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Chloromethyl Ketones / pharmacology
  • Animals
  • COS Cells
  • Caspase 14
  • Caspase Inhibitors
  • Caspases / biosynthesis*
  • Caspases / metabolism
  • Cell Differentiation / physiology
  • Chlorocebus aethiops
  • Cloning, Molecular
  • Escherichia coli / enzymology
  • Humans
  • Keratinocytes / cytology
  • Oligopeptides / metabolism
  • Rats
  • Substrate Specificity


  • Amino Acid Chloromethyl Ketones
  • Caspase Inhibitors
  • Oligopeptides
  • benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone
  • tryptophyl-glutamyl-histidyl-aspartic acid
  • CASP14 protein, human
  • Caspase 14
  • Caspases