A regulatory sequence found in the 5' terminal regions of a variety of RNA species. The sequence starts with a CYTIDINE, which is followed by a stretch of 5 to 15 PYRIMIDINE NUCLEOTIDES. Messenger RNA that contains the 5' Terminal Oligo Pyrimidine tract is often referred to as 5' TOP mRNA. The sequence acts as a translational regulator and has been found in mRNAs for PEPTIDE ELONGATION FACTORS and RIBOSOMAL PROTEINS.
