Eukaryotic cytosolic 80S ribosome (80S ribosome)

The eukaryotic cytosolic 80S ribosome is the primary molecular machinery responsible for protein synthesis in the cytoplasm of eukaryotic cells [1.2.1, 1.5.1]. It is a massive ribonucleoprotein complex composed of two subunits: the small 40S subunit (containing 18S rRNA and approximately 33 proteins) and the large 60S subunit (containing 28S, 5.8S, and 5S rRNAs and approximately 47 proteins) [1.3.2, 1.5.1]. The ribosome facilitates the translation of genetic information from messenger RNA (mRNA) into functional proteins through a coordinated cycle of initiation, elongation, termination, and recycling [1.4.1, 1.4.2]. In many diseases, particularly cancer, ribosome biogenesis and translation rates are significantly upregulated to support the high biomass requirements of rapidly proliferating cells [1.2.2, 1.3.2]. Drugs such as omacetaxine mepesuccinate (homoharringtonine) target the 80S ribosome by binding to the A-site cleft, thereby inhibiting the elongation phase of translation and preferentially reducing the levels of short-lived oncogenic proteins like BCR-ABL, MYC, and MCL1 [1.6.2, 1.6.3]. While the ribosome is a validated therapeutic target in hematological malignancies, its essential role in all cells presents challenges regarding systemic toxicity and myelosuppression [1.3.5, 1.6.1].

Other names

Human 80S ribosomeCytosolic ribosomeEukaryotic ribosome80S translation machinery80S translation complex

Inhibition of protein synthesis by binding to functional sites such as the A-site cleft, peptidyl transferase center (PTC), or peptide exit tunnel (PET), thereby blocking translation elongation, initiation, or termination.