Search results
Results from the WOW.Com Content Network
As discussed below, many additional targets for phosphorylation by MAPK were later found, and the protein was renamed "mitogen-activated protein kinase" (MAPK). The series of kinases from RAF to MEK to MAPK is an example of a protein kinase cascade. Such series of kinases provide opportunities for feedback regulation and signal amplification.
The first mitogen-activated protein kinase to be discovered was ERK1 in mammals. Since ERK1 and its close relative ERK2 are both involved in growth factor signaling, the family was termed "mitogen-activated". With the discovery of other members, even from distant organisms (e.g. plants), it has become increasingly clear that the name is a ...
Mitogen-activated protein kinase kinase (also known as MAP2K, MEK, MAPKK) is a dual-specificity kinase enzyme which phosphorylates mitogen-activated protein kinase (MAPK). MAP2K is classified as EC 2.7.12.2 .
Mitogen-activated protein kinase kinase kinase 4 is an enzyme that in humans is encoded by the MAP3K4 gene. [5] [6]The central core of each mitogen-activated protein kinase (MAPK) pathway is a conserved cascade of 3 protein kinases: an activated MAPK kinase kinase (MAPKKK) phosphorylates and activates a specific MAPK kinase (MAPKK), which then activates a specific MAPK.
The MAP kinase-kinase, which activates ERK, was named "MAPK/ERK kinase" . [5] Receptor-linked tyrosine kinases, Ras, Raf, MEK, and MAPK could be fitted into a signaling cascade linking an extracellular signal to MAPK activation. [6] See: MAPK/ERK pathway. Transgenic gene knockout mice lacking MAPK1 have major defects in early development. [7]
The p38 MAPK is regulated by MEKK 1-4 and TAO 1/2 families of MAPKKKs and is responsible for inflammation, apoptosis, cell differentiation, and cell cycle regulation. The determination for what cascade is followed is based upon the type of signal, the strength of binding, and the length of binding. [5] [9]
[3] [4] For example, RasGTP signals link with the mitogen activated protein kinase (MAPK) cascade to amplify the allosteric activation of proliferative transcription factors such as Myc and CREB. Earl Wilbur Sutherland Jr., discovered second messengers, for which he won the 1971 Nobel Prize in Physiology or Medicine.
RAF kinases participate in the RAS-RAF-MEK-ERK signal transduction cascade, also referred to as the mitogen-activated protein kinase (MAPK) cascade. [11] Activation of RAF kinases requires interaction with RAS-GTPases. The three RAF kinase family members are: A-RAF; B-RAF; c-Raf