11.3 Essentials of Molecular Cloning If cells express the foreign gene and its expression can be detected,then screening is relatively easy ·Antibodies Blood serum proteins produced by animals Made by injecting animal with specific protein antigen May need to look for the DNA if gene is not expressed Nucleic acid probes Look for binding of labeled nucleic acid probe to DNA from specific colonies Chen Feng,Lecture of MicrobiologyChen Feng, Lecture of Microbiology 11.3 Essentials of Molecular Cloning If cells express the foreign gene and its expression can be detected, then screening is relatively easy • Antibodies • Blood serum proteins produced by animals • Made by injecting animal with specific protein antigen May need to look for the DNA if gene is not expressed • Nucleic acid probes • Look for binding of labeled nucleic acid probe to DNA from specific colonies