Lohmer S, Maddaloni M, Motto M, Salamini F, Thompson R D
Max-Planck-Institut für Züchtungsforschung, Köln, Germany.
Plant Cell. 1993 Jan;5(1):65-73. doi: 10.1105/tpc.5.1.65.
The protein encoded by the Opaque-2 (O2) gene is a transcription factor, translated from an mRNA that possesses an unusually long 5' leader sequence containing three upstream open reading frames (uORFs). The efficiency of translation of O2 mRNA has been tested in vivo by a transient assay in which the level of activation of the b32 promoter, a natural target of O2 protein, is measured. We show that uORF-less O2 alleles possess a higher transactivation value than the wild-type allele and that the reduction in transactivation due to the uORFs is a cis-dominant effect. The data presented indicate that both uORF1 and uORF2 are involved in the reducing effect and suggest that both are likely to be translated.
不透明-2（O2）基因编码的蛋白质是一种转录因子，由一种mRNA翻译而来，该mRNA具有异常长的5'前导序列，其中包含三个上游开放阅读框（uORF）。通过瞬时测定法在体内测试了O2 mRNA的翻译效率，其中测量了O2蛋白的天然靶标b32启动子的激活水平。我们表明，无uORF的O2等位基因比野生型等位基因具有更高的反式激活值，并且由于uORF导致的反式激活降低是一种顺式显性效应。所呈现的数据表明，uORF1和uORF2都参与了降低效应，并表明两者都可能被翻译。
