2.A.28.1.9
Sodium/bile acid cotransporter (Cell growth-inhibiting gene 29 protein; Na^+/bile acid cotransporter; Na⁺/taurocholate transport protein; NTCP; Solute carrier family 10 member 1). Transports steroids and xenobiotics, including HMG-CoA reductase inhibiitors (statins). This protein is the hepatitis B and D virus receptor (Yan et al. 2012). Specific inhibitors are known and include cyclosporin A (Wu et al. 2020, Slijepcevic and van de Graaf 2017).  hNTCP-membrane vesicles effectively prevent viral infection, spreading, and replication in a human-liver-chimeric mouse model of HBV infection (Liu et al. 2018). The dye, indocyaine green (ICG), is a substrate, and NTCP and ICG form a reporter system with applications in cancer biology, robust drug-drug interactions, and drug screening in HBV/HDV infections (Wu et al. 2020). Structural plasticity is a feature of rheostat positions in the Human Na⁺/taurocholate cotransporting polypeptide (NTCP) (Ruggiero et al. 2022). Findings on protein-protein interactions (PPIs) between NTCP and cofactors relevant for entry of the virus/NTCP receptor complex have been summarized (Zakrzewicz and Geyer 2023).  Hepatitis B virus (HBV) is a globally prevalent human DNA virus responsible for over 250 million cases of chronic liver infections, leading to conditions such as liver inflammation, cirrhosis and hepatocellular carcinoma (HCC). Sodium taurocholate co-transporting polypeptide (NTCP) is highly expressed in human hepatocytes and functions as a bile acid (BA) transporter. NTCP is the receptor that HBV and its satellite virus, hepatitis delta virus (HDV), use to enter hepatocytes. HBV entry into hepatocytes is tightly regulated by various signaling pathways, and NTCP plays an important role in the initial stage of HBV infection. NTCP acts as an initiation signal, causing metabolic changes in hepatocytes, facilitating the entry of HBV into hepatocytes. Li et al. 2024 examined the regulatory mechanisms governing HBV pre-S1 binding to liver membrane NTCP, the role of NTCP in HBV internalization, and the transcriptional and translational regulation of NTCP expression. Additionally, they discussed clinical drugs targeting NTCP, including combination therapies involving NTCP inhibitors.  Sodium taurocholate co-transporting polypeptide (NTCP) has been identified as an entry receptor for hepatitis B virus (HBV). Manganese is a potent inducer of lysosomal activity that inhibits de novo hepatitis B virus (HBV) infection (Yu et al. 2025).