Figure 2

Cis -elements of cyclin mRNAs that control their translation. Translation of mRNAs of budding yeast (S.c) CLN3, fission yeast (S.p) Cig2 and Cdc13, and human cyclin E1 is controlled by uORFs, IRES or structured 5' UTR. The 5' UTR of the budding yeast CLB3 mRNA is responsible for its translational control but the underlying mechanism is unclear. Translation of Drosophila (Droso) and Xenopus (Xeno) type-A cyclin mRNAs is regulated by the Bruno family of RNA binding proteins (RBPs) that bind to the cis-elements within their 3' UTR. Expression of vertebrate cyclin B is controlled by CPEB-mediated cytoplasmic polyadenylation and translational control. Expression of two human G1/S cyclins, e.g. cyclins D1 and E2, is regulated by miRNAs.