MARK2
MARK2 (microtubule affinity regulating kinase 2) is a serine/threonine protein kinase of the Par-1 family that regulates cell polarity and microtubule dynamics. It is also known as PAR-1, Par1b, PAR-1B and EMK1, and was previously named ELKL motif kinase. Browse Assay Genie's current range of MARK2 research reagents below, or read on for the biology behind the target.
MARK2 is a serine/threonine protein kinase involved in cell polarity and the regulation of microtubule dynamics. It phosphorylates the microtubule-associated proteins MAP2, MAP4 and MAPT/TAU at KXGS motifs, which causes them to detach from microtubules and leads to microtubule disassembly. Through this activity it controls microtubule stability. Other reported substrates include CRTC2/TORC2, DCX, HDAC7, KIF13B and RAB11FIP2.
In epithelial cells, MARK2 regulates polarity by phosphorylating RAB11FIP2 and is essential for the asymmetric development of membrane domains. It modulates the developmental decision to build a columnar rather than a hepatic epithelial cell, apparently by promoting a switch from direct to transcytotic apical protein delivery. In neurons it is required for neurite outgrowth and establishment of polarity, and it regulates axogenesis by phosphorylating KIF13B, which promotes KIF13B binding to 14-3-3. It may also regulate neuronal migration, possibly through DCX. MARK2 phosphorylates HDAC7, promoting its interaction with 14-3-3 and export from the nucleus, and acts as a positive regulator of Wnt signalling, probably by phosphorylating disheveled proteins (DVL1, DVL2 and/or DVL3). During ER stress or starvation-induced autophagy it phosphorylates UBAC2 at Ser-223, promoting interaction with GABARAP to mediate ER-phagy.
The MARK2 gene belongs to the HGNC group of microtubule affinity regulating kinases and encodes a member of the CAMK Ser/Thr protein kinase family, SNF1 subfamily. The protein localises to the cell membrane, including the lateral membrane, as well as the cytoplasm, cytoskeleton and dendrites. Multiple transcript variants encoding different isoforms have been described. Mouse and rat both carry a Mark2 ortholog, and MARK3 is a related family member.
MARK2 is a key regulator of polarity in epithelial and neuronal cells, including the asymmetric organisation of membrane domains.
By phosphorylating MAP2, MAP4 and TAU at KXGS motifs, MARK2 controls their release from microtubules and so microtubule stability.
MARK2 is required for neurite outgrowth and neuronal polarity, and acts on KIF13B and DCX in axogenesis and migration.
MARK2 positively regulates Wnt signalling via disheveled proteins and phosphorylates UBAC2 to support ER-phagy.
MARK2 is a serine/threonine kinase that regulates cell polarity and microtubule dynamics. It phosphorylates MAP2, MAP4 and TAU at KXGS motifs, causing them to detach from microtubules. It also acts on RAB11FIP2, KIF13B, HDAC7 and disheveled proteins, linking polarity to neuronal and epithelial development.
MARK2 is also called PAR-1, Par1b, PAR-1B and EMK1. Earlier names were ELKL motif kinase and MAP/microtubule affinity-regulating kinase 2. UniProt lists the protein as serine/threonine-protein kinase MARK2. Multiple transcript variants encoding different isoforms have been reported.
Yes. Mouse and rat each have an ortholog named Mark2. In humans MARK2 belongs to the microtubule affinity regulating kinase group alongside MARK3, within the SNF1 subfamily of CAMK kinases. Check the datasheet of any product for its validated reactivity.
MARK3, another member of the microtubule affinity regulating kinase group, with related polarity and cytoskeleton targets at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q7KZI7; product specifications from Assay Genie datasheets.