6.6 Gene Expression and Cell Specialization

Explain how the binding of transcription factors to promoter regions affects gene expression and the phenotype of the organism.

• RNA polymerase and transcription factors bind to promoter or enhancer DNA sequences to initiate transcription. These sequences can be upstream or downstream of the transcription start site.
• Negative regulatory molecules inhibit gene expression by binding to DNA and blocking transcription.

Explain the connection between the regulation of gene expression and phenotypic differences in cells and organisms.

• Gene regulation results in differential gene expression and influences cell products and functions.
• Certain small RNA molecules have roles in regulating gene expression.