Journal
PLANT AND CELL PHYSIOLOGY
Volume 51, Issue 2, Pages 294-301Publisher
OXFORD UNIV PRESS
DOI: 10.1093/pcp/pcp190
Keywords
Azuki bean (Vigna angularis); Catalytic unit; Cellulose synthesis; Rosette; Sucrose synthase
Categories
Ask authors/readers for more resources
Cellulose synthesis in plants is believed to be carried out by the plasma membrane-associated rosette structure which can be observed by electron microscopy. Despite decade-long speculation, it had not been demonstrated whether the rosette is the site of catalytic activity of cellulose synthesis. To determine the relationship between this structure and cellulose synthesis, we successfully isolated detergent-insoluble rosettes from the plasma membrane of bean epicotyls. However, the purified rosettes did not possess cellulose synthesis activity invitro. Conversely, detergent-soluble granular particles of 9.510nm diameter were also isolated and exhibited UDP-glucose binding activity and possessed -1,4-glucan (cellulose) synthesis activity invitro. The particle, referred to as the catalytic unit of cellulose synthesis, was enriched with a 78kDa polypeptide which was verified as sucrose synthase like by mass spectrometry and immunoblotting. The catalytic units were able to bind to the rosettes and retained the cellulose synthesis activity in the presence of UDP-glucose or sucrose plus UDP when supplemented with magnesium. The incorporation of the catalytic unit into the rosette structure was confirmed by immunogold labeling with anti-sucrose synthase antibodies under an electron microscope. Our results suggest that the plasma membrane-associated rosette anchors the catalytic unit of cellulose synthesis to form the functional cellulose synthesis machinery.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available