Final answer:
Without specific experimental results, it's not possible to determine if Myc-tagged or FLAG-tagged DHFR should have shown up in tubulin. The choice of tag in such an experiment depends on many factors, including the availability of specific antibodies and the design of the experiment.
Step-by-step explanation:
The question pertains to the experimental tagging of diydrofolate reductase (DHFR), a protein, with different molecular tags to determine its interaction with another protein known as tubulin. Without the specific experimental context or results, it's generally not possible to assert which tagged form of DHFR should have shown up in tubulin. The question likely derives from an experiment where such a tagging and interaction were observed, but to answer this, more context or data regarding the particular experiment is essential. Tagging of proteins, such as with Myc or FLAG tags, is a common technique used in molecular biology to track proteins and their interactions within cells. These tags are epitopes that can be recognized by specific antibodies, making it possible to track proteins in various assays, including co-immunoprecipitation or Western blotting, where interactions between different proteins can be analyzed. The choice between Myc and FLAG tags for a protein would be based on various factors, including the specificity of antibodies available and the experimental design.