RMP24 (ribonuclease MRP subunit p24, also known as C18orf21) is a metazoan-specific protein component of the RNase MRP ribonucleoprotein complex 1. As an integral subunit unique to RNase MRP, RMP24 stabilizes the catalytic RNA of the complex and is essential for pre-rRNA processing at internal transcribed spacer 1 (ITS1) site 2 2. RMP24 functions within RNase MRP to facilitate 40S ribosome biogenesis and cell proliferation, distinguishing it from the related RNase P enzyme which processes tRNA precursors 3. Structurally, RMP24 displays homology to yeast RNase MRP-specific components and RNase P's RPP21 subunit, but contains specific regions that confer selective association with RNase MRP rather than RNase P 3. The complex employs a 'double-anchor' substrate-binding mechanism involving RMP24 that enables broad RNA-targeting specificity and ribosome assembly 4. RMP24 is indispensable for protein synthesis and chondrogenesis 4. Disease-associated mutations in related RNase MRP subunits impair complex assembly 3, suggesting RMP24 mutations may similarly compromise ribosome biogenesis and cellular function.