The “Frankenplasmid” lab: An investigative exercise for teaching recombinant DNA methods

Abstract

We describe an investigative laboratory module designed to give college undergraduates strong practical and theoretical experience with recombinant DNA methods within 3 weeks. After deducing restriction enzyme maps for two different plasmids, students ligate the plasmids together in the same reaction, transform E. coli with this mixture of ligated DNA, and plate the cells on media that specifically select for hybrid plasmids. The main goal of the assignment is for students to deduce the gene map of one hybrid ''Frankenplasmid'' using the LacZ phenotype of its transformants, PCR, and restriction mapping. Our protocol results in a number of possible outcomes, meaning that students are mapping truly unknown plasmids. The open-ended nature of this assignment results in an effective module that teaches recombinant DNA procedures while engaging students with its investigative approach, increasing complexity, and puzzle-like quality. Moreover, the modular design of the activity allows it to be adapted to a more limited schedule, introductory courses, or more advanced courses.

Promoting Inquiry-Based Teaching in Laboratory Courses: Are We Meeting the Grade?

“…, 2008 ; Dean and Wilder, 2011 ). For example, Dean and Wilder (2011) assessed their students who carried out a recombinant DNA exercise using a survey developed by Sleister (2007) to assess her students who isolated yeast mutants. The most commonly used published instrument, and the only instrument used in more than one study ( n = 3), was the SALG.…”

“…In other cases, studies used instruments that had been developed in the context of similar laboratory courses ( Marshall, 2007 ; Simmons et al. , 2008 ; Dean and Wilder, 2011 ). For example, Dean and Wilder (2011) assessed their students who carried out a recombinant DNA exercise using a survey developed by Sleister (2007) to assess her students who isolated yeast mutants.…”