The 5' ends of yeast killer factor RNAs are pppGp.

The 5' nucleotides of the double-stranded RNAs of yeast killer factor have been isolated by digestion with pancreatic, T1 and T2 RNase followed by two-dimensional electrophoresis. They were identified by bacterial alkaline phosphatase and snake venom phosphodiesterase digestions. Both the larger double-stranded RNA (L, of 2.5 x 10(6) daltons) and the smaller double-stranded RNA (M, of 1.4 x 10(6) daltons) have the 5' end groups pppGp. These 5' ends are dissimilar to those of the double-stranded RNAs of animal viruses but may be characteristic of the 5' ends of the double-stranded RNAs of fungal viruses.