Small RNAs reveal two target sites of the RNA-maturation factor Mbb1 in the chloroplast of Chlamydomonas.

ABSTRACT: Many chloroplast transcripts are protected against exonucleolytic degradation by RNA-binding proteins. Such interactions can lead to the accumulation of short RNAs (sRNAs) that represent footprints of the protein partner. By mining existing data sets of Chlamydomonas reinhardtii small RNAs, we identify chloroplast sRNAs. Two of these correspond to the 5'-ends of the mature psbB and psbH messenger RNAs (mRNAs), which are both stabilized by the nucleus-encoded protein Mbb1, a member of the tetratricopeptide repeat family. Accordingly, we find that the two sRNAs are absent from the mbb1 mutant. Using chloroplast transformation and site-directed mutagenesis to survey the psbB 5' UTR, we identify a cis-acting element that is essential for mRNA accumulation. This sequence is also found in the 5'

SUBMITTER: Loizeau K 

PROVIDER: S-EPMC3950674 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature