Identification, characterization, and DNA sequence of a functional "double" groES-like chaperonin from chloroplasts of higher plants.
AUTOR(ES)
Bertsch, U
RESUMO
Chloroplasts of higher plants contain a nuclear-encoded protein that is a functional homolog of the Escherichia coli chaperonin 10 (cpn10; also known as groES). In pea (Pisum sativum), chloroplast cpn10 was identified by its ability to (i) assist bacterial chaperonin 60 (cpn60; also known as groEL) in the ATP-dependent refolding of chemically denatured ribulose-1,5-bisphosphate carboxylase and (ii) form a stable complex with bacterial cpn60 in the presence of Mg.ATP. The subunit size of the pea protein is approximately 24 kDa--about twice the size of bacterial cpn10. A cDNA encoding a spinach (Spinacea oleracea) chloroplast cpn10 was isolated, sequenced, and expressed in vitro. The spinach protein is synthesized as a higher molecular mass precursor and has a typical chloroplast transit peptide. Surprisingly, however, attached to the transit peptide is a single protein, comprised of two distinct cpn10 molecules in tandem. Moreover, both halves of this "double" cpn10 are highly conserved at a number of residues that are present in all cpn10s that have been examined. Upon import into chloroplasts the spinach cpn10 precursor is processed to its mature form of approximately 24 kDa. N-terminal amino acid sequence analysis reveals that the mature pea and spinach cpn10 are identical at 13 of 21 residues.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=49987Documentos Relacionados
- Identification of a groES-like chaperonin in mitochondria that facilitates protein folding.
- Identification and functional analysis of chaperonin 10, the groES homolog from yeast mitochondria.
- Identification, Characterization, and Mapping of Expressed Sequence Tags from an Embryonic Zebrafish Heart cDNA Library
- Identification, characterization, and sequence analysis of a cDNA encoding a phosphoprotein of human herpesvirus 6.
- Identification, characterization, and sequence analysis of a cDNA encoding a phosphoprotein of human herpesvirus 6.