Many RNA recognition motif (RRM)-containing proteins are known to exist in chloroplasts. Major members of the RRM protein family, which are chloroplast ribonucleoproteins (cpRNPs), have been investigated in seed plants, including tobacco and Arabidopsis thaliana, but never in early land plants, such as bryophytes. In this study, we surveyed RRM proteins encoded in the moss Physcomitrella patens genome and predicted 25 putative chloroplast RRM proteins. Among them, two RRM-containing proteins, PpRBP2a and PpRBP2b, resembled cpRNPs and were thus referred to as cpRNP-like proteins. However, knockout mutants of either one or two PpRBP2 genes exhibited a wild type-like phenotype. Unlike Arabidopsis cpRNPs, the levels of mRNA accumulation in chloroplasts were not affected in the PpRBP2 knockout mutants. In addition, the efficiency of RNA editing was also not altered in the mutants. This suggests that PpRBP2a and 2b may be functionally distinct from Arabidopsis cpRNPs., H. Uchiyama, M. Ichinose, M. Sugita., and Obsahuje bibliografické odkazy
The growth response of Chlorella sorokiniana to certain irradiance, DO, and temperature demonstrated the possible causes of low productivity with this strain in outdoor cultures. The growth (biomass productivity) and chlorophyll fluorescence (Fv/Fm) were substantially reduced when the dissolved oxygen (above 200 % of air saturation) and temperature were elevated. and C. U. Ugwu, H. Aoyagi, H. Uchiyama.