Cpc2, but not snoU24b RNA, is important for Gcn2 regulation.
A, small nucleolar RNA U24b is encoded within the intron of cpc2 mRNA. Gray box, coding sequence; dashed line, intron; solid line, untranslated region. The position encoding Trp43 is indicated by an arrowhead. B, gene expression levels of cpc2, snoU24b, and cdk9+ (control) were analyzed by quantitative RT-PCR from wild-type (YT3033), cpc2Δ (YT2307), and cpc2_W43* (YT4299) cells. All data are normalized to the expression level of 18 S rRNA, and the average expression level of two independent experiments is shown as the relative fold to those in wild-type cells. C, 10-fold serial dilutions of wild-type (JK317), cpc2Δ (YT3540), and cpc2_W43* (YT4299) cells were spotted on EMM plates ± 10 mm 3AT. D, immunoblots of anti-FLAG-Gcn2 immunoprecipitates from Flag:gcn2 (YT3372) and Flag:gcn2 cpc2_W43* (YT4309) cells treated with 10 mm 3AT, probed with anti-phospho-Gcn2 and anti-FLAG (control) antibodies.