Kinase Family Syk

Kinase Classification: Group TK: Family Syk

Evolution

Syk kinases are found in animals, including sponge, and have two members in mammals: Syk and ZAP-70. Syk is absent from nematodes

Domain Structure

Syks have dual SH2 domains followed by a tyrosine kinase domain. The single Drosophila homolog, shark, has two ankyrin repeats between the SH2 domains, and homologs are found in sponge and sea urchin, but not in mammals.

Functions

Human Syk and ZAP-70 are best known for their role in T cell receptor (TCR) signaling and also in B cell receptor (BCR) signaling, and are predominantly expressed in hematopoeitic lineages.