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Updated: Apr 3, 2026
Western Blotting: Sample Preparation to Detection
Published on: October 14, 2010
Southwestern Blotting Assay
Yinshan Jia1, Linda Nagore1, Harry Jarrett2
1Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA.
Abstract:
Southwestern blotting is a technique used to study DNA-protein interactions. This method detects specific DNA-binding proteins by incubating radiolabeled DNA with a gel blot, washing, and visualizing through autoradiography. A blot resulting from 1-dimensional SDS-PAGE reveals the molecular weight of the binding proteins. To increase separation and determine isoelectric point a 2-dimensional gel can be blotted. Additional dimensions of electrophoresis, such as a gel shift (EMSA), can precede isoelectric focusing and SDS-PAGE to further improve separation. Combined with other techniques, such as mass spectrometry, the DNA-binding protein can be identified.
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01:15Western Blotting
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02:57Southern Blot
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