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Evolving views of pectin biosynthesis.
Melani A Atmodjo1, Zhangying Hao, Debra Mohnen
1Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602-4712, USA. matmodjo@ccrc.uga.edu
Annual Review of Plant Biology
|March 5, 2013
Summary
New discoveries in pectin synthesis reveal key proteins and complexes involved in plant cell wall formation. Two models are proposed for pectin biosynthesis, advancing our understanding of this complex polysaccharide family.
Area of Science:
- Plant Biology
- Biochemistry
- Molecular Biology
Background:
- Pectin, a complex plant cell wall polysaccharide, has a poorly understood synthesis pathway.
- Recent advancements include identifying pectin biosynthetic proteins and proteoglycans.
Purpose of the Study:
- To propose a framework for understanding pectin biosynthesis.
- To present two hypothetical models for pectin synthesis.
Main Methods:
- Identification and characterization of pectin biosynthetic enzymes.
- Functional confirmation of glycosyltransferases.
- Analysis of the GAUT1:GAUT7 homogalacturonan biosynthetic complex.
Main Results:
- Four pectin biosynthetic glycosyltransferases have been functionally confirmed.
- Multiple putative pectin glycosyl- and methyltransferases identified.
- The GAUT1:GAUT7 complex exhibits a novel Golgi retention mechanism and interacts with 12 proteins.
Conclusions:
- A framework for pectin biosynthesis is emerging.
- Two models, the consecutive glycosyltransferase and domain synthesis models, are proposed for pectin synthesis.
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