Dual specificity mitogen-activated protein kinase kinase 5, PB1 domain (IPR034851)

Short name: PB1_MAP2K5

Overlapping homologous superfamilies


Domain relationships

  • PB1 domain (IPR000270)
    • Dual specificity mitogen-activated protein kinase kinase 5, PB1 domain (IPR034851)


Mitogen-activated protein kinase kinase 5 (MAP2K5, alias MEK5) is a member of the ERK5 pathway, involved in angiogenesis and development [PMID: 12221099, PMID: 15601854]. ERK5 is a MAPK activated in response to various stimuli through a three-tier cascade constituting MEK5 and MEKK2/3. MEK5 phosphorylates the activation loop of ERK5 at Thr218 and Tyr220 leading to its activation [PMID: 7759517]. The PB1 domain of MEK5 interacts with the PB1 domains of other members of the kinase cascade, MEKK2 and MEKK3 [PMID: 12912994].

The PB1s are dimerization/oligomerization domains present in adaptor and scaffold proteins as well as kinases and serve to organize platforms that ensure specificity and fidelity during cellular signalling [PMID: 16949360]. The interaction between two PB1 domain depends on the type of PB1. There are three types of PB1 domains: type I which contains an OPCA motif, acidic aminoacid cluster, type II which contains a basic cluster, and type I/II which contains both an OPCA motif and a basic cluster. The Map2k5 protein contains a type I PB1 domain [PMID: 17726178].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.