Yeast ribosomal P0 protein has two separate binding sites for P1/P2 proteins.
The ribosome has a distinct lateral protuberance called the stalk; in eukaryotes it is formed by the acidic ribosomal P-proteins which are organized as a pentameric entity described as P0-(P1-P2)(2). Bilateral interactions between P0 and P1/P2 proteins have been studied extensively, however, the region on P0 responsible for the binding of P1/P2 proteins has not been precisely defined. Here we report a study which takes the current knowledge of the P0 - P1/P2 protein interaction beyond the recently published information. Using truncated forms of P0 protein and several in vitro and in vivo approaches, we have defined the region between positions 199 and 258 as the P0 protein fragment responsible for the binding of P1/P2 proteins in the yeast Saccharomyces cerevisiae. We show two short amino acid regions of P0 protein located at positions 199-230 and 231-258, to be responsible for independent binding of two dimers, P1A-P2B and P1B-P2A respectively. In addition, two elements, the sequence spanning amino acids 199-230 and the P1A-P2B dimer were found to be essential for stalk formation, indicating that this process is dependent on a balance between the P1A-P2B dimer and the P0 protein.
Department of Molecular Biology, Institute of Microbiology and Biotechnology, Maria Curie-Skodowska University, Akademicka 19, 20-033 Lublin, Poland.
Dawid
D
Krokowski
Aleksandra
A
Boguszewska
Dariusz
D
Abramczyk
Anders
A
Liljas
Marek
M
Tchórzewski
Nikodem
N
Grankowski
D000595:Amino Acid Sequence; D001665:Binding Sites; D008969:Molecular Sequence Data; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D025941:Protein Interaction Mapping; D012269:Ribosomal Proteins / Q000235:genetics / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D017384:Sequence Deletion
D010750:Phosphoproteins; C056003:RPP1A protein, S cerevisiae; C503572:RPP2B protein, S cerevisiae; D012269:Ribosomal Proteins; D029701:Saccharomyces cerevisiae Proteins; C054675:ribosomal protein P0