CREB-1

from Wikipedia, the free encyclopedia
CREB-1
CREB-1
Ribbon model of the dimer on DNA according to PDB  1DH3
Properties of human protein
Mass / length primary structure 341 amino acids
Cofactor Mg 2+
Identifier
Gene name CREB1
External IDs
Occurrence
Parent taxon Vertebrates

CREB (more precisely: CREB-1 ) represents English cAMP response element-binding protein . It is a well-studied transcription factor .

Role in the cell

CREB has a so-called bZIP domain with which it forms a homodimer , i.e. it binds to itself and thus forms a fork structure. This can specifically bind to the cAMP Response Element sequence (CRE); these are specific nucleotide sequences in the promoter of certain genes . The binding causes an increased transcription of this gene. However, the dimer is only formed after phosphorylation of CREB by a protein kinase . CREB thus forms an end point of a signal transduction cascade , that is, a cell can be stimulated by an external signal to activate individual genes. The first way to activate CREB was described by signal transduction via cAMP and protein kinase A, among others by Nobel Prize winner Eric Kandel , who gave CREB its name. In the meantime, further signal transduction cascades are known which also phosphorylate CREB, for example extracellular-signal-regulated kinase (ERK).

The activation of genes via CREB is well conserved in the animal world and also occurs in humans. Many G protein-coupled receptors react via CREB, for example the glucagon receptor, which controls gluconeogenesis . CREB also influences the formation of long-term memory in nerve cells .

CREB and internal clock

In some vertebrates, CREB influences the circadian rhythm of the internal clock . Using CREB, a new synchronization can take place via light pulses. Light stimuli are picked up by the eye and transmitted to neurons in the suprachiasmatic nucleus via the retinohypothalamic tract . The action potentials are finally transformed into neurochemical signals via the neurotransmitter glutamate or PACAP and open calcium channels in the cells of the suprachiasmatic nucleus . The calcium influx activates certain kinases that phosphorylate CREB. CREB binds to the CRE box of period1, an essential part of the oscillator, and can interact with co-activators through the newly acquired phosphate groups. This leads to an increase in per1 expression. Phase shifts and ergo resynchronization can result from this.

literature

  • A. Barco, CH Bailey, ER Kandel: Common molecular mechanisms in explicit and implicit memory. In: Journal of Neurochemistry. 97, 2006, pp. 1520-1533.
  • MR Montminy, GA Gonzalez, KK Yamamoto: Regulation of cAMP-inducible genes by CREB. In: Trends Neurosci. 13 (5), 1990, pp. 184-188. PMID 1693237 .
  • DD Ginty, JM Kornhauser, MA Thompson, H. Bading, KE Mayo, JS Takahashi, ME Greenberg: Regulation of CREB phosphorylation in the suprachiasmatic nucleus by light and a circadian clock. In: Science. 260 (5105), Apr 9, 1993, pp. 238-241.

See also

Individual evidence

  1. ↑ Homologues at OMA

Web links