p27Kip1 Antibody SX53G8 / CDKN1B Monoclonal Antibody [clone SX53G8] (V2086)

Description

The p27Kip1 Antibody SX53G8 / CDKN1B Monoclonal Antibody recognizes cyclin-dependent kinase inhibitor 1B, a member of the Cip/Kip family of cell cycle regulators. Also known as p27 or KIP1, this protein is encoded by the CDKN1B gene and plays a central role in controlling the transition from G1 to S phase. By binding to cyclin-dependent kinase complexes, particularly cyclin E-CDK2 and cyclin A-CDK2, p27 restricts cell cycle progression and helps coordinate proliferation with extracellular growth signals.

p27 abundance is regulated through transcriptional, translational, and post-translational mechanisms. Phosphorylation influences its stability, subcellular localization, and interactions with cyclin-CDK complexes. Phosphorylation at threonine 187 promotes recognition by the SCF-SKP2 ubiquitin ligase complex, leading to proteasomal degradation. This mechanism allows cells to reduce p27 levels as they commit to DNA replication. Conversely, conditions that favor cell cycle arrest frequently promote p27 accumulation and sustained inhibition of CDK activity.

Although predominantly associated with nuclear cell cycle control, p27 also performs functions in the cytoplasm. Its localization is influenced by phosphorylation and interactions with regulatory proteins, including components of the PI3K-AKT signaling pathway. Cytoplasmic p27 can influence actin organization, cell migration, and interactions with Rho family GTPases. These activities demonstrate that p27 contributes to cellular behavior beyond its established role as a negative regulator of proliferation.

CDKN1B is widely studied in cancer biology because reduced nuclear p27 expression is associated with aggressive behavior and unfavorable outcomes in several tumor types. Unlike many classical tumor suppressors, CDKN1B is frequently dysregulated through altered protein stability or localization rather than direct genetic inactivation. Germline pathogenic variants are also associated with multiple endocrine neoplasia type 4, highlighting its importance in endocrine tumor suppression. Beyond cancer, p27 contributes to differentiation, tissue development, and the maintenance of cellular quiescence. NSJ Bioreagents offers this p27Kip1 Antibody for investigating the regulation of p27 abundance and localization in relation to proliferation, differentiation, and tumor biology.

Explore related targets involved in cell cycle regulation, proliferation, and differentiation in our Cell Biology Antibodies collection.

Application Notes

The concentration stated for each application is a general starting point. Variations in protocols, secondaries and substrates may require the p27Kip1 Antibody SX53G8 / CDKN1B Monoclonal Antibody to be titered up or down for optimal performance.

1. Staining of formalin-fixed tissues requires boiling tissue sections in 10mM citrate buffer, pH 6.0, for 10-20 min followed by cooling at RT for 20 minutes.
2. The prediluted format is supplied in a dropper bottle and is optimized for use in IHC. After epitope retrieval step (if required), drip mAb solution onto the tissue section and incubate at RT for 30 min.

Immunogen

Purified GST-p27 fusion protein of human origin was used as the immunogen for this p27Kip1 antibody.

Storage

Store the p27Kip1 antibody at 2-8oC (with azide) or aliquot and store at -20oC or colder (without azide).

Alternate Names

CDKN1B antibody, p27 antibody, KIP1 antibody, Cyclin-Dependent Kinase Inhibitor 1B antibody