CREB

Definition

CREB, or cAMP response element-binding protein, is a transcription factor that plays a vital role in the regulation of gene expression in response to various signaling pathways. It functions by binding to specific DNA sequences called cAMP response elements, promoting the transcription of target genes that are crucial for processes like memory formation and cellular growth. This makes CREB a key player in cell signaling and communication, connecting external signals to internal cellular responses.

5 Must Know Facts For Your Next Test

1. CREB is activated by phosphorylation through various kinases, such as PKA (Protein Kinase A) and CaMKIV (Calcium/Calmodulin-dependent Protein Kinase IV).
2. Once activated, CREB binds to the cAMP response element in the promoter region of target genes, facilitating their transcription.
3. It is crucial for long-term potentiation (LTP) in neurons, a cellular mechanism underlying learning and memory.
4. CREB also regulates genes involved in cell survival and proliferation, linking it to important pathways in cancer biology.
5. Dysregulation of CREB has been implicated in several neurodegenerative diseases and mood disorders, highlighting its importance in both health and disease.

Review Questions

• How does the activation of CREB influence gene expression and what are some of its physiological effects?
  • The activation of CREB influences gene expression by allowing it to bind to specific DNA sequences known as cAMP response elements. This binding promotes the transcription of genes involved in critical physiological processes such as memory formation and neuronal plasticity. As a result, CREB plays an essential role in learning and memory while also regulating genes associated with cell survival and growth.
• Discuss the mechanisms through which CREB is activated and how these mechanisms integrate with cellular signaling pathways.
  • CREB is primarily activated through phosphorylation by kinases like Protein Kinase A (PKA) and Calcium/Calmodulin-dependent Protein Kinase IV (CaMKIV). These kinases are activated by upstream signaling molecules such as hormones or neurotransmitters that elevate cyclic AMP (cAMP) levels. Once phosphorylated, CREB undergoes a conformational change that enhances its ability to bind DNA and activate gene transcription, thereby linking extracellular signals to intracellular responses.
• Evaluate the role of CREB in both healthy brain function and its potential implications in neurological disorders.
  • In healthy brain function, CREB is crucial for processes such as long-term potentiation, which underlies learning and memory. It activates genes necessary for synaptic plasticity and neuron survival. However, when CREB function is disrupted, it can lead to impaired memory and has been implicated in neurological disorders such as Alzheimer's disease and depression. Understanding CREB's dual role highlights its potential as a therapeutic target for improving cognitive function or treating mood disorders.

Related terms

Transcription Factor: A protein that binds to specific DNA sequences to regulate the transcription of genetic information from DNA to messenger RNA.

cAMP: Cyclic adenosine monophosphate, a second messenger molecule that transmits signals from hormones and neurotransmitters to trigger various cellular responses.

Gene Expression: The process by which information from a gene is used to synthesize a functional gene product, typically proteins, which play critical roles in cellular function.