Accumulation of sweet protein monellin is regulated by the psbA 5 ' UTR in tobacco chloroplasts
Abbreviated Journal Title
J. Plant Biol.
chloroplast transformation; endonucleolytic activation; monellin; psbA 5; ' UTR; sweet protein; translation efficiency; POLYCISTRONIC MESSENGER-RNAS; 5' UNTRANSLATED REGION; GENE-EXPRESSION; HOMOLOGOUS RECOMBINATION; CHLAMYDOMONAS-REINHARDTII; POLY(A)-BINDING; PROTEIN; 5'-UNTRANSLATED REGION; TRANSLATION EFFICIENCY; PLANTS; DEGRADATION; Plant Sciences
Post-transcriptional RNA processing and translational regulations are important steps for gene expression. To analyze the 5'UTR of psbA that enhances translation of the sweet protein monellin in chloroplasts, we cloned the monellin gene, with and without the psbA 5'UTR, into the chloroplast expression vector for chloroplast transformation. Transgenic plants were identified as being transplastomic via PCR and Southern blot analyses. We also observed non-specific recombination during tobacco chloroplast transformation. Analyses of the transcription patterns showed that intercistronic cleavage of the psbA mRNA 5' untranslated (UTR) region was functional at the mature stage, with the monocistronic mRNA of monellin increasing while its dicistronic mRNA decreased. Moreover, monellin accumulation accounted for 2.3% of the total soluble protein at the mature stage, but only 1.3% at the young stage in transplastomic lines that contained the 5'UTR of psbA. These results suggest that activation of the endonucleolytic cleavage of the psbA 5'UTR element depends on chloroplast developmental conditions, and that it enhances the accumulation of sweet protein monellin in those chloroplasts.
Journal of Plant Biology
"Accumulation of sweet protein monellin is regulated by the psbA 5 ' UTR in tobacco chloroplasts" (2006). Faculty Bibliography 2000s. 6516.