Skip to main content
. 2011 Feb 23;155(4):1520–1532. doi: 10.1104/pp.110.171231

Figure 1.

Figure 1.

Sequestration of a segment of single-stranded RNA by a long PPR tract may account for many functions attributed to PPR proteins. This is exemplified by PPR10, which stabilizes specific processed RNA termini (A) and enhances translation (B) by sequestering the same RNA segment (Pfalz et al., 2009; Prikryl et al., 2011). Analogous interactions could influence RNA processing, stability, and translation in other ways. A, Site-specific barrier activity of PPR10 defines processed RNA termini. The processed RNA termini derived from polycistronic transcripts spanning atpI and atpH are shown at the top. PPR10 binds this intergenic region and promotes the accumulation of processed RNAs by blocking exoribonucleases intruding from either direction. The processed atpI and atpH transcripts derive from different precursor molecules. B, Site-specific RNA-remodeling activity of PPR10 enhances translation. The atpH ribosome-binding site (RBS) is sequestered in a duplex with a portion of the PPR10-binding site. PPR10 binding frees the atpH ribosome-binding site for translation (Pfalz et al., 2009; Prikryl et al., 2011).