POLYADENYLATION OF C-MOS MESSENGER-RNA AS A CONTROL POINT IN XENOPUS MEIOTIC MATURATION

c-mos protein, encoded by a proto-oncogene, is essential for the meiot ic maturation of frog oocytes. Polyadenylation of c-mos messenger RNA is shown here to be a pivotal regulatory step in meiotic maturation. M aturation is prevented by selective amputation of polyadenylation sign als from c-mos mRNA. Injection of a prosthetic RNA, which restores c-m os polyadenylation signals by base pairing to the amputated mRNA, resc ues maturation and can stimulate translation in trans. Prosthetic RNAs may provide a general strategy by which to alter patterns of mRNA exp ression in vivo.