UNIPROT #

O95997

PROTEIN NAME

Securin

SYNONYMS

AW555095 antibody; C87862 antibody; Cut2 antibody; EAP 1 antibody; EAP1 antibody; ESP1 associated protein 1 antibody; Esp1-associated protein antibody; hPTTG antibody; MGC126883 antibody; MGC138276 antibody; Pds1 antibody; Pituitary tumor transforming 1 antibody; Pituitary tumor transforming protein 1 antibody; Pituitary tumor-transforming 1, isoform CRA_a antibody; Pituitary tumor-transforming 1, isoform CRA_b antibody; Pituitary tumor-transforming gene 1 antibody; Pituitary tumor-transforming gene 1 protein antibody; PTTG 1 antibody; PTTG antibody; PTTG1 antibody; PTTG1 protein antibody; PTTG1_HUMAN antibody; Pttg3 antibody; Securin antibody; Tumor transforming 1 antibody; Tumor transforming protein 1 antibody; Tumor-transforming protein 1 antibody; TUTR 1 antibody; TUTR1 antibody

SEQUENCE SIMILARITIES

Belongs to the securin family.

TISSUE SPECIFICITY

Expressed at low level in most tissues, except in adult testis, where it is highly expressed. Overexpressed in many patients suffering from pituitary adenomas, primary epithelial neoplasias, and esophageal cancer.

DEVELOPMENTAL STAGE

Low level during G1 and S phases. Peaks at M phase. During anaphase, it is degraded.

POST-TRANSLATIONAL MODIFICATION

Phosphorylated at Ser-165 by CDK1 during mitosis.; Phosphorylated in vitro by ds-DNA kinase.; Ubiquitinated through 'Lys-11' linkage of ubiquitin moieties by the anaphase promoting complex (APC) at the onset of anaphase, conducting to its degradation. 'Lys-11'-linked ubiquitination is mediated by the E2 ligase UBE2C/UBCH10.

SUBCELLULAR LOCATION

Nucleus. Cytoplasm.

FUNCTION

The product of the oncogene PTTG, pituitary tumor transforming gene, is a human homolog of the anaphase-inhibitor vertebrate protein, securin. PTTG contains a basic amino-terminal domain and an acidic carboxy-terminal domain, which acts as a transactivation domain when fused to a heterologous DNA binding domain. Human PTTG is overexpressed in Jurkat and is also detected in human thymus, testis and placenta. PTTG is mainly expressed in the cytoplasm and is also partially localized to the nucleus. Vertebrate PTTG regulates the separin Esp1, which promotes chromatid separation, to overcome the cohesive forces that hold sister chromatids together. This regulatory function of PTTG suggests that defective regulation of cohesion may contribute to cancer by promoting chromosome instability. Although vertebrate PTTG shares cell-cycle functions with its yeast securin counterparts Pds1p and Cut2, none share sequence homology.