Endonuclease, hydrolyzes highly polymerized RNA, poly(U) and poly(C), and the dinucleotides CpA and UpA. More active towards rCA than rUA or rUG. Has cytotoxic activity against cultured human submaxillary gland carcinoma cells. Monomer. There are at least five different forms arising from glycan heterogeneity. Major (most represented) glycoform 1. Major (second-most represented) glycoform 2. Minor glycoform 3. Minor glycoform 4. Minor (least represented) glycoform 5. Belongs to the pancreatic ribonuclease family.