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Updated: May 6, 2026
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Phloem Sap Sampling from Brassica napus for 3D-PAGE of Protein and Ribonucleoprotein Complexes
Published on: January 9, 2018
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The broccoli (Brassica oleracea) phloem tissue proteome
James A Anstead1, Steven D Hartson, Gary A Thompson
1College of Agricultural Sciences, The Pennsylvania State University, University Park, PA 16802, USA. aphidfreak@hotmail.com.
BMC Genomics
|November 8, 2013
Summary
Researchers developed a new method to isolate phloem tissue for comprehensive proteomic analysis. This approach identified nearly 400 proteins, revealing phloem
Area of Science:
- Plant Biology
- Proteomics
- Molecular Biology
Background:
- Phloem transports essential organic compounds throughout plants.
- Understanding phloem proteins is crucial for plant physiology.
- Previous studies focused mainly on soluble proteins in phloem sap.
Purpose of the Study:
- To develop a method for comprehensive proteomic analysis of phloem tissue.
- To identify membrane-bound and associated proteins in the phloem.
- To characterize novel phloem-specific genes and proteins.
Main Methods:
- Developed a simple dissection procedure to isolate phloem tissue from Brassica oleracea.
- Utilized light microscopy and fluorescently labeled antibodies to confirm sieve element density.
- Employed sequential protein extraction using soluble protein extraction, SDS, and CHAPSO detergents.
Main Results:
- Successfully isolated Brassica oleracea phloem tissue with a high density of sieve elements.
- Identified nearly 400 proteins across three different extraction methods.
- Demonstrated that combining extraction protocols enhances proteomic depth and identifies diverse proteins.
Conclusions:
- Phloem tissue is rich in proteins involved in stress responses and structural functions.
- Identified novel genes highly expressed in phloem tissue.
- The developed method provides a more comprehensive understanding of phloem proteome.
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