TAO2 (Ser181) (TAOK2) Antibody – Rabbit Polyclonal

This gene encodes a serine/threonine protein kinase that is involved in many different processes, including, cell signaling, microtubule organization and stability, and apoptosis. Alternatively spliced transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Oct 2011]

Function: Serine/threonine-protein kinase involved in different processes such as membrane blebbing and apoptotic bodies formation DNA damage response and MAPK14/p38 MAPK stress-activated MAPK cascade. Phosphorylates itself, MBP, activated MAPK8, MAP2K3, MAP2K6 and tubulins. Activates the MAPK14/p38 MAPK signaling pathway through the specific activation and phosphorylation of the upstream MAP2K3 and MAP2K6 kinases. In response to DNA damage, involved in the G2/M transition DNA damage checkpoint by activating the p38/MAPK14 stress-activated MAPK cascade, probably by mediating phosphorylation of upstream MAP2K3 and MAP2K6 kinases. Isoform 1, but not isoform 2, plays a role in apoptotic morphological changes, including cell contraction, membrane blebbing and apoptotic bodies formation. This function, which requires the activation of MAPK8/JNK and nuclear localization of C-terminally truncated isoform 1, may be linked to the mitochondrial CASP9-associated death pathway. Isoform 1 binds to microtubules and affects their organization and stability independently of its kinase activity. Prevents MAP3K7-mediated activation of CHUK, and thus NF-kappa-B activation, but not that of MAPK8/JNK. May play a role in the osmotic stress-MAPK8 pathway. Isoform 2, but not isoform 1, is required for PCDH8 endocytosis. Following homophilic interactions between PCDH8 extracellular domains, isoform 2 phosphorylates and activates MAPK14/p38 MAPK which in turn phosphorylates isoform 2. This process leads to PCDH8 endocytosis and CDH2 cointernalization. Both isoforms are involved in MAPK14 phosphorylation. Ref.1 Ref.2 Ref.10 Ref.11 Ref.12 Ref.13 Ref.14 Ref.15

Catalytic activity: ATP + a protein = ADP + a phosphoprotein.

Cofactor: Magnesium

By similarity.

Enzyme regulation: Selectively inhibited by the enantiopure organoruthenium inhibitor 9E1. Activated following arsenic trioxide (As2O3) treatment. Ref.17 Ref.19

Subunit structure: Interacts with MAP2K3 and MAP2K6

By similarity. Self-associates. Interacts with tubulins through the C-terminal domain. Interacts with MAP3K7 and interfers with MAP3K7-binding to CHUK and thus prevents NF-kappa-B activation. Isoform 2 interacts with PCDH8; this complex may also include CDH2

By similarity. Ref.10 Ref.11 Ref.13

Subcellular location: Cytoplasmic vesicle membrane; Multi-pass membrane protein

Potential. Cytoplasm › cytoskeleton. Nucleus. Note: Catalytically active full-length phosphorylated isoform 1 localizes to microtubules in the cytoplasm predominantly on microtubule cables positioned around the nucleus. A C-terminally truncated form of isoform 1 is present in the nucleus; isoform 2 and kinase-defective, as well as full-length isoform 1 are excluded from the nucleus. Ref.2 Ref.11 Ref.15Isoform 2: Cell projection › dendrite. Note: In dendrites, colocalizes with PCDH8

By similarity. Ref.2 Ref.11 Ref.15

Tissue specificity: Ubiquitously expressed, with a higher level of expression in testis and brain. Ref.1 Ref.2

Post-translational modification: Isoforms 1 and 2 are autophosphorylated. Ref.14 Ref.15C-terminal cleavage of isoform 1 and subsequent nuclear localization requires CASP9 activity.Autophosphorylated. Phosphorylated by ATM.Isoform 2:Phosphorylated on Ser-1031 by MAPK14. This phosphorylation is required PCDH8 for endocytosis

By similarity.

Sequence similarities: Belongs to the protein kinase superfamily. STE Ser/Thr protein kinase family. STE20 subfamily.Contains 1 protein kinase domain.

Sequence caution: The sequence AAQ89301.1 differs from that shown. Reason: Erroneous initiation. Translation N-terminally extended.The sequence BAA74904.2 differs from that shown. Reason: Erroneous initiation. Translation N-terminally shortened.