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Published on: June 14, 2020
Immunological characterization of two dominant tonoplast polypeptides
1Institut für Botanik und Pharmazeutische Biologie, Julius-Maximilians-Universität Würzburg, Mittlerer Dallenbergweg 64, 8700 Würzburg, Germany.
Plant Physiology
|December 1, 1991
Summary
Two tonoplast polypeptides from barley (Hordeum vulgare) were identified and studied. These 31 and 40 kilodalton proteins are intrinsically localized and widely distributed across plant and animal kingdoms.
Area of Science:
- Plant Biology
- Cell Biology
- Biochemistry
Background:
- Vacuoles are key organelles in plant cells, and their tonoplast membrane harbors numerous proteins involved in transport and homeostasis.
- Understanding the composition and localization of tonoplast proteins is crucial for elucidating vacuolar functions.
Purpose of the Study:
- To identify and characterize specific tonoplast polypeptides in barley (Hordeum vulgare) mesophyll vacuoles.
- To investigate the localization, distribution, and properties of these identified polypeptides.
Main Methods:
- Two-dimensional separation of tonoplast membrane proteins.
- Production of antisera against isolated 31 and 40 kilodalton polypeptides.
- Immunological localization studies on isolated vacuoles and plant tissues.
- Biochemical fractionation and chromatography of membrane proteins.
Main Results:
- Two intrinsic tonoplast polypeptides of 31 and 40 kilodaltons were identified in barley.
- These polypeptides remain associated with membranes after harsh treatments, indicating intrinsic localization.
- Antiserum against the 31 kDa polypeptide binds to the vacuole's outer surface.
- The 31 and 40 kDa polypeptides are distinct from major acid hydrolases and tend to aggregate.
Conclusions:
- The identified 31 and 40 kDa polypeptides are integral components of the barley tonoplast.
- These tonoplast proteins exhibit a broad distribution across various plant species and even in animal liver tissues.
- The findings suggest a conserved role for these polypeptides in vacuole-containing organisms.
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