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1. Mitogen-activated protein kinase
(MAP kinase)
Supervised by
Dr. Chinar M.Muhammad
Prepared by
Fadel Adnan Muhammed
University of Zakho
Faculty of Science
Department of Biology

2. Mitogen-activated protein kinase (MAPK) is a
pivotal signaling pathway governing cell
processes like proliferation and response to
external signals. It involves a cascade of
protein kinases transmitting signals from cell
surface receptors to the nucleus, influencing
gene expression and cellular functions.
Introduction

3. MAP kinase pathway
Its a signal transduction cascade that plays a central role
in transmitting signals from the cell surface to the
nucleus, influencing various cellular processes. It
typically consists of three main kinases:
1. MAP3K
2. MAP2K
3. MAPK

4. MAP kinase pathway

5. MAP kinase pathway
1. Initiation:
• External signals, such as growth factors or stress, activate cell surface
receptors.
• This activation triggers a series of phosphorylation events, ultimately
activating MAP3K.
2. Amplification:
• MAP3K phosphorylates and activates MAP2K.
• MAP2K, in turn, phosphorylates and activates MAPK.

6. 3. Transduction to Nucleus:
• Activated MAPK translocates to the nucleus, where it phosphorylates
various transcription factors.
• This phosphorylation alters gene expression, influencing cellular
responses.
4. Cellular Responses:
• The MAPK pathway regulates diverse processes, including cell
proliferation, differentiation, apoptosis, and responses to
environmental stress.
5. Termination:
• Negative feedback mechanisms and phosphatases help in deactivating
the pathway, ensuring a controlled cellular response.
MAP kinase pathway

7. MAP kinase pathway
The Chart kinases can be grouped into three main families. In
mammals, these are
1. ERKs (extracellular- signal- regulation related kinases),
2. JNKs (Jun amino-terminal kinases),
3. p38/ SAPKs (stress- actuated protein kinases).
• ERKs
to regulate cell proliferation, differentiation, and response to external
signals.
• JNKs
to regulate cellular responses to stress, inflammation, and apoptosis.
• p38/ SAPKs
to regulate cellular responses to stress and inflammation.