A functional genomics experiment is carried out in E. coli to examine global levels of gene expression in various types of minimal growth medium. RNA extracted from the experimental culture is labeled with a molecule that fluoresces red, and RNA extracted from the control culture is labeled with a molecule that fluoresces green. The experimental and control samples are mixed prior to hybridization. Shown here are spots on the microarray corresponding to five genes: trpE (the first gene in the tryptophan biosynthetic operon), lacI, lacZ, lacY, and crp (which encodes the cAMP receptor protein). Color the spots red, green, or yellow according to the relative levels of expression of each gene in the experimental and control cultures. (Hint: Before answering, think carefully about how the cAMP receptor protein co-regulates the lac operon.).

1. A functional genomics experiment is carried out in E. coli to examine global levels of gene
expression in various types of minimal growth medium. RNA extracted from the experimental
culture is labeled with a molecule that fluoresces red, and RNA extracted from the control culture
is labeled with a molecule that fluoresces green. The experimental and control samples are mixed
prior to hybridization. Shown here are spots on the microarray corresponding to five genes: trpE
(the first gene in the tryptophan biosynthetic operon), lacI, lacZ, lacY, and crp (which encodes the
cAMP receptor protein). Color the spots red, green, or yellow according to the relative levels of
expression of each gene in the experimental and control cultures. (Hint: Before answering, think
carefully about how the cAMP receptor protein co-regulates the lac operon.)