Related Experiment Videos
Molecular identification of a putative human hyaluronan synthase
1Burnham Institute, California 92037, USA.
The Journal of Biological Chemistry
|September 20, 1996
Summary
Researchers identified a novel human gene, Has2, crucial for producing hyaluronan (a key molecule in cell proliferation). This discovery advances understanding of hyaluronan synthesis and its role in cellular processes.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- Hyaluronan (HA) is a vital glycosaminoglycan involved in cell proliferation, differentiation, and tissue hydration.
- The mammalian enzyme responsible for HA synthesis, hyaluronan synthase, remained largely uncharacterized at the molecular level.
Purpose of the Study:
- To identify and characterize the mammalian hyaluronan synthase enzyme.
- To elucidate the molecular basis of hyaluronan synthesis in human cells.
Main Methods:
- Cloning of a human cDNA homologous to bacterial hyaluronan synthase (HasA) and Xenopus DG42.
- Sequence analysis to predict protein structure and functional domains.
- Transfection of the cloned cDNA (named Has2) into human and Chinese hamster ovary cells.
- Analysis of hyaluronan production and Has2 mRNA expression in different cell states.
Main Results:
- A novel human cDNA, Has2, was cloned, encoding a 63.6 kDa protein with significant homology to known synthases.
- Has2 shares 55% amino acid identity with Xenopus DG42 and 52% with mouse HAS.
- Transfection of Has2 increased hyaluronan production significantly in human (34-fold) and CHO cells (9-fold).
- Has2 mRNA was highly expressed in proliferating fibroblasts but absent in growth-arrested cells.
Conclusions:
- The Has2 protein is a critical component of the human hyaluronan synthase system.
- Has2 expression is linked to cellular proliferation, suggesting its role in regulating HA synthesis during cell growth.
- This finding provides a molecular target for understanding and potentially manipulating hyaluronan metabolism.