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Heterodimer formation is essential for heparanase enzymatic activity
- Source :
-
Biochemical & Biophysical Research Communications . Sep2003, Vol. 308 Issue 4, p885. 7p. - Publication Year :
- 2003
-
Abstract
- Heparanase is an endo-β-d-glucuronidase involved in cleavage of heparan sulfate residues and hence participates in extracellular matrix degradation and remodeling. The heparanase cDNA encodes for a polypeptide of 543 amino acids that appears as a ∼65 kDa band in SDS–PAGE analysis. The protein undergoes a proteolytic cleavage that is likely to occur at two potential cleavage sites, Glu109–Ser110 and Gln157–Lys158, yielding an 8 kDa polypeptide at the N-terminus, a 50 kDa polypeptide at the C-terminus, and a 6 kDa linker polypeptide that resides in-between. The active form of heparanase has long been thought to be a 50 kDa polypeptide isolated from cells and tissues. However, attempts to obtain heparanase activity after expression of the 50 kDa polypeptide failed, suggesting that the N-terminal region is important for heparanase enzymatic activity. It has been hypothesized that heterodimer formation between the 8 and 50 kDa heparanase subunits is important for heparanase enzymatic activity. By individually or co-expressing the 8 and 50 kDa heparanase subunits in mammalian cells, we demonstrate specific association between the heparanase subunits by means of co-immunoprecipitation and pull-down experiments. Moreover, a region in the 50 kDa heparanase subunit that mediates interaction with the 8 kDa subunit was identified. Altogether, our results clearly indicate that heterodimer formation is necessary and sufficient for heparanase enzymatic activity in mammalian cells. [Copyright &y& Elsevier]
- Subjects :
- *GLUCURONIDASE
*EXTRACELLULAR matrix
*AMINO acids
Subjects
Details
- Language :
- English
- ISSN :
- 0006291X
- Volume :
- 308
- Issue :
- 4
- Database :
- Academic Search Index
- Journal :
- Biochemical & Biophysical Research Communications
- Publication Type :
- Academic Journal
- Accession number :
- 10567831
- Full Text :
- https://doi.org/10.1016/S0006-291X(03)01478-5