Dioxin, produced as a byproduct of various industrial chemical processes, is suspected of contributing to the development of cancer and birth defects in animals and humans. It apparently acts by entering cells by simple diffusion and binding to proteins in the cytoplasm, then altering the pattern of gene expression. Which of the following are likely to be the cytoplasmic proteins to which dioxin binds?
A. growth factor receptors
B. enhancers
C. DNA polymerases
D. nucleosomes
E. transcription factors
Answer: E