&CHAPTER 11

Transgenic Plant Analysis

JANICE ZALE

Department of Plant Sciences, University of Tennessee, Knoxville, Tennessee

11.0. CHAPTER SUMMARY AND OBJECTIVES

11.0.1 Summary

Once transgenic plants are produced, they must be analyzed using methods common to

molecular biology. The transgene might initially be probed by using the polymerase

chain reaction, but eventually DNA hybridization (Southern blot) analysis must be per-

formed to assess transgene integration. To gauge transgene expression, RNA hybridization

(northern blot) analysis is done, but real-time reverse transcriptase PCR is commonly used.

So, Southern blot tells whether and how many copies of the DNA transgene are integrated

into the genome, and northern blot is useful for determining how much of the transgene is

transcribed. However, analysis eventually centers around how much transgenically

expressed protein is produced: using western blot analysis or enzyme-linked immunosor-

bent assay (ELISA).

11.0.2 Discussion Questions

1. Through what type of chemical bond does the complementary probe bind to the
   nucleic acid?


2. Nucleic acids and proteins are separated according to size in agarose and sodium
   dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) gels, respectively.
   Why do both types of macromolecules migrate toward the anode in an electrical
   current?


3. What is gene expression, and how can you measure it?


4. Explain why phenotypic data provide evidence of transformation but not conclusive
   proof of transformation.


5. What factors are most important when designing a Southern blot experiment to test
   for transgenic status?

Plant Biotechnology and Genetics: Principles, Techniques, and Applications, Edited by C. Neal Stewart, Jr.

Copyright#2008 John Wiley & Sons, Inc.

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