CSP41, a sequence-specific chloroplast mRNA binding protein, is an endoribonuclease.
- 1 August 1996
- journal article
- Published by Oxford University Press (OUP) in Plant Cell
- Vol. 8 (8) , 1409-1420
- https://doi.org/10.1105/tpc.8.8.1409
Abstract
Correct 3' processing of chloroplast precursor mRNAs (pre-mRNAs) requires a stem-loop structure within the 3' untranslated region. In spinach, a stable 3' stem-loop-protein complex has been shown to form in vitro between petD pre-mRNA, encoding subunit IV of the cytochrome b6/f complex, and chloroplast proteins. This complex contains three chloroplast stem-loop binding proteins (CSPs), namely, CSP29, CSP41, and CSP55. Here, we report the purification of CSP41 and cloning of the csp41 gene and show that CSP41 is encoded by a single nuclear gene. Characterization of bacterially expressed CSP41 demonstrates that this protein binds specifically to the 3' stem-loop structure and a downstream AU-rich element of petD pre-mRNA and that its binding affinity is enhanced by associating with CSP55. Our data also show that CSP41 has substantial nonspecific endoribonuclease activity. These data suggest that CSP41 could be involved in 3' processing of petD pre-mRNA and/or in RNA degradation. The fact that different reaction conditions favor RNA binding over ribonuclease activities suggests a possible mode of in vivo regulation.Keywords
This publication has 35 references indexed in Scilit:
- A protein complex mediating mRNA degradation in Escherichia coliMolecular Microbiology, 1994
- Conserved Structures and Diversity of Functions of RNA-Binding ProteinsScience, 1994
- Characterization of a cDNA encoding a novel type of RNA-binding protein in tobacco: its expression and nucleic acid-binding propertiesMolecular Genetics and Genomics, 1994
- RNA-Binding Protein from ArabidopsisPlant Physiology, 1993
- Functional in vivo analyses of the 3′ flanking sequences of the Chlamydomonas chloroplast rbcL and psaB genesMolecular Genetics and Genomics, 1993
- Sequence-Specific Binding of Transfer RNA by Glyceraldehyde-3-Phosphate DehydrogenaseScience, 1993
- In-gel digestion of proteins for internal sequence analysis after one- or two-dimensional gel electrophoresisAnalytical Biochemistry, 1992
- Histone 3' ends: essential and regulatory functions.1992
- Primary structure of nuclease P1 from Penicillium citrinumEuropean Journal of Biochemistry, 1991
- A 3' stem/loop structure of the Chlamydomonas chloroplast atpB gene regulates mRNA accumulation in vivo.Plant Cell, 1991