Final answer:
The correct answer is option C. In E. coli, the heat-shock response is mediated by Heat-shock proteins (chaperones). These proteins assist in refolding misfolded proteins during stress conditions such as increased temperatures to maintain cellular function.
Step-by-step explanation:
In E. coli, the heat-shock response, which alters the proteins produced by the cell at different temperatures, is mediated by Heat-shock proteins (chaperones). These heat-shock proteins (HSPs) are crucial in protecting the cell from stress conditions such as increased temperature by helping to refold misfolded proteins. When a heat shock occurs, it can cause proteins within the cell to denature or lose their shape, which impairs their function. Chaperones aid in the refolding of these proteins to maintain cellular function and protect the cell from damage caused by these stressful conditions.
Heat-shock proteins are released from the nuclear receptor/HSP complex as a direct response to the increased temperature, which is a signal for the dissociation of this complex (option C). This in turn results in the activation of the transcription of HSP genes. The cell responds to a heat shock by increasing the activity of proteins that help refold misfolded proteins because maintaining the proper structure and function of proteins is essential for cell survival.
The correct option for the question on how the heat-shock response in E. coli is mediated is C) Heat-shock proteins (chaperones).