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In situ Subcellular Fractionation of Adherent and Non-adherent Mammalian Cells
Published on: July 23, 2010
Mammalian cells contain a second nucleocytoplasmic hexosaminidase
Martin Gutternigg1, Dubravko Rendić, Regina Voglauer
1Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria.
The Biochemical Journal
|December 2, 2008
Summary
Researchers have identified and characterized the molecular nature of hexosaminidase D, a previously obscure enzyme. This novel enzyme, encoded by HEXDC genes, plays a role in cellular function and is a new class 20 glycosidase.
Area of Science:
- Biochemistry
- Molecular Biology
- Enzymology
Background:
- Mammalian cells possess two cytosolic hexosaminidases.
- One hexosaminidase has been characterized and is crucial for cleaving beta-N-acetylglucosamine residues from proteins.
- The molecular identity of the second enzyme, hexosaminidase D, remained unknown.
Purpose of the Study:
- To molecularly characterize the human and murine recombinant forms of hexosaminidase D.
- To investigate the properties and localization of this novel enzyme.
Main Methods:
- Molecular characterization of human and murine recombinant enzymes encoded by HEXDC genes.
- Analysis of substrate specificity, pH dependency, and temperature stability.
- Localization studies using a Myc-tagged hexosaminidase D form.
Main Results:
- The human and murine recombinant enzymes encoded by HEXDC genes were characterized and identified as hexosaminidase D.
- The enzyme exhibits specific substrate specificity, pH dependency, and temperature stability.
- A Myc-tagged form of hexosaminidase D showed nucleocytoplasmic localization.
- HEXDC gene transcripts are expressed in various murine tissues.
- This enzyme represents the third identified mammalian class 20 glycosidase.
Conclusions:
- Hexosaminidase D has been molecularly characterized for the first time.
- The characterized enzyme exhibits properties consistent with hexosaminidase D and localizes to the nucleocytoplasm.
- This discovery expands the known classes of mammalian glycosidases.
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