RNase A, also known as ribonuclease A or pancreatic RNase, is an endonuclease that digests single-stranded RNA and specifically cleaves after pyrimidine nucleotides. Native bovine RNase A consists of 124 residues, a mass of approximately 13.7 kDa, and forms a homodimer. Its enzymatic activity is activated by potassium and sodium salts. RNase A is often used in removing RNA contaminants from DNA or protein samples, and in RNA protection assays.