4-Thiouridine, RNA synthesis inhibitor

Supplementary information

This supplementary information is collated from multiple sources and compiled automatically.

P-glycoprotein also known as P-gp MDR1 transporter or ABCB1 is a well-characterized efflux transporter with a molecular mass of approximately 170 kDa. This protein is expressed in various normal tissues such as the liver intestine kidney blood-brain barrier and placenta. It is located on the cell membrane where it functions to expel a wide variety of substrates out of cells using energy derived from ATP hydrolysis. This capability of pumping out toxins and xenobiotics makes P-glycoprotein an important player in cellular detoxification.

Biological function summary

P-glycoprotein acts as a protective mechanism against toxic substances and drugs within the body. It is a member of the ATP-binding cassette (ABC) transporter family which is critical for their ability to transport molecules across membranes. P-glycoprotein is not typically part of a larger protein complex but can interact with other membrane proteins to facilitate its function. Its role in drug metabolism and excretion is vital for maintaining the balance and elimination of harmful substances.

Pathways

P-glycoprotein plays a significant role in the pharmacokinetics of drugs within the body. This transporter is involved in the multi-drug resistance (MDR) pathway which impacts the efficacy of chemotherapeutic agents. P-glycoprotein also interacts with other proteins like CYP3A4 which is involved in the metabolism of many drugs. These interactions affect the concentration and distribution of therapeutic agents contributing to the body's overall drug response.

P-glycoprotein is closely associated with multi-drug resistance in cancer where its overexpression can lead to reduced effectiveness of chemotherapy. It is also implicated in disorders of the central nervous system like epilepsy where it affects drug delivery to the brain. The protein has connections with CYP3A4 in these contexts where both together influence drug metabolism and efficacy complicating treatment regimens and therapeutic outcomes in these conditions.