CABIN1

Calcineurin plays an important role in the T-cell receptor-mediated signal transduction pathway. The protein encoded by this gene binds specifically to the activated form of calcineurin and inhibits calcineurin-mediated signal transduction. The encoded protein is found in the nucleus and contains a leucine zipper domain as well as several PEST motifs, sequences which confer targeted degradation to those proteins which contain them. Alternative splicing results in multiple transcript variants encoding two different isoforms.

calcineurin binding protein 1

May be required for replication-independent chromatin assembly. May serve as a negative regulator of T-cell receptor (TCR) signaling via inhibition of calcineurin. Inhibition of activated calcineurin is dependent on both PKC and calcium signals. Acts as a negative regulator of p53/TP53 by keeping p53 in an inactive state on chromatin at promoters of a subset of it's target genes.

Cell surface receptor signaling pathway Source: UniProtKB
DNA replication-independent nucleosome assembly Source: UniProtKB

Nucleus

Activated through PKC-mediated hyperphosphorylation. Phosphorylation by the DNA damage kinases ATM and CHK2 enhances ubiquitination.
Upon genotoxic stress, ubiquitination by the DCX(DDB2) E3 ubiquitin-protein ligase complex targets CABIN1 for proteasomal degradation, leading to the release of p53/TP53.