POLR3A (RNA Polymerase III Subunit A): POLR3A is a key subunit of RNA polymerase III, the enzyme responsible for producing small RNAs such as tRNAs, 5S rRNA, and other non-coding RNAs. It plays an essential role in transcribing genes needed for protein synthesis and other vital cellular processes. Mutations in POLR3A have been associated with neurological diseases and developmental disorders, highlighting its critical importance to cellular function and human health.