Explain how the regulation of gene expression at the transcriptional level contributes to the coordinated response of a cell to an environmental stress.

1. Cells sense stress (e.g. heat, oxidative) via receptors or damage signals.
2. Stress‑activated transcription factors (e.g. heat‑shock factor, NF‑κB) bind specific DNA sequences in promoters.
3. Binding recruits RNA polymerase II and co‑activators, increasing transcription of protective genes (e.g. HSPs, antioxidant enzymes).
4. Rapid up‑regulation restores homeostasis and prevents damage, showing transcriptional control is essential for coordinated stress responses.