Recombinant Human Securin (PTTG1)

Uniprot Id

O95997

Target Species

Human

Target Name

PTTG1

Target Full Name

Securin

Target Function

Regulatory protein, which plays a central role in chromosome stability, in the p53/TP53 pathway, and DNA repair. Probably acts by blocking the action of key proteins. During the mitosis, it blocks Separase/ESPL1 function, preventing the proteolysis of the cohesin complex and the subsequent segregation of the chromosomes. At the onset of anaphase, it is ubiquitinated, conducting to its destruction and to the liberation of ESPL1. Its function is however not limited to a blocking activity, since it is required to activate ESPL1. Negatively regulates the transcriptional activity and related apoptosis activity of TP53. The negative regulation of TP53 may explain the strong transforming capability of the protein when it is overexpressed. May also play a role in DNA repair via its interaction with Ku, possibly by connecting DNA damage-response pathways with sister chromatid separation.

Target Subcellular Location

Cytoplasm. Nucleus.

Target Protein Families

Securin family

Target 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.

Target Synonyms

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

Target Background

The encoded protein is a homolog of yeast securin proteins, which prevent separins from promoting sister chromatid separation. It is an anaphase-promoting complex (APC) substrate that associates with a separin until activation of the APC. The gene product has transforming activity in vitro and tumorigenic activity in vivo, and the gene is highly expressed in various tumors. The gene product contains 2 PXXP motifs, which are required for its transforming and tumorigenic activities, as well as for its stimulation of basic fibroblast growth factor expression. It also contains a destruction box (D box) that is required for its degradation by the APC. The acidic C-terminal region of the encoded protein can act as a transactivation domain. The gene product is mainly a cytosolic protein, although it partially localizes in the nucleus. Three transcript variants encoding the same protein have been found for this gene.