Linked Life Data

2898472

Source:http://linkedlifedata.com/resource/pubmed/id/2898472

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
1988-8-8
pubmed:databankReference
pubmed:abstractText
We have shown that the individual members of the plant gene family for glutamine synthetase (GS) are differentially expressed in vivo, and each encode distinct GS polypeptides which are targeted to different subcellular compartments (chloroplast or cytosol). At the polypeptide level, chloroplast GS (GS2) and cytosolic GS (GS1 and GSn) are distinct and show an organ-specific distribution. We have characterized full length cDNA clones encoding chloroplast or cytosolic GS of pea. In vitro translation products encoded by three different GS cDNA clones, correspond to the mature GS2, GS1, and GSn polypeptides present in vivo. pGS185 encodes a precursor to the chloroplast GS2 polypeptide as shown by in vitro chloroplast uptake experiments. The pGS185 translation product is imported into the chloroplast stroma and processed to a polypeptide which corresponds in size and charge to that of mature chloroplast stromal GS2 (44 kDa). The 49 amino terminal amino acids encoded by pGS185 are designated as a chloroplast transit peptide by functionality in vitro, and amino acid homology to other transit peptides. The cytosolic forms of GS (GS1 and GSn) are encoded by highly homologous but distinct mRNAs. pGS299 encodes the cytosolic GS1 polypeptide (38 kDa), while pGS341 (Tingey, S. V., Walker, E. L., and Coruzzi, G. M. (1987) EMBO. J. 6, 1-9) encodes a cytosolic GSn polypeptide (37 kDa). The homologous nuclear genes for chloroplast and cytosolic GS show different patterns of expression in vivo. GS2 expression in leaves is modulated by light, at the level of steady state mRNA and protein, while the expression of cytosolic GS is unaffected by light. The light-induced expression of GS2 is due at least in part to a phytochrome mediated response. Nucleotide sequence analysis indicates that chloroplast and cytosolic GS have evolved from a common ancestor and suggest a molecular mechanism for chloroplast evolution.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
263
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
9651-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:2898472-Amino Acid Sequence, pubmed-meshheading:2898472-Base Sequence, pubmed-meshheading:2898472-Cell Nucleus, pubmed-meshheading:2898472-Chloroplasts, pubmed-meshheading:2898472-Cytosol, pubmed-meshheading:2898472-DNA, pubmed-meshheading:2898472-DNA, Recombinant, pubmed-meshheading:2898472-Electrophoresis, Polyacrylamide Gel, pubmed-meshheading:2898472-Fabaceae, pubmed-meshheading:2898472-Gene Expression Regulation, pubmed-meshheading:2898472-Glutamate-Ammonia Ligase, pubmed-meshheading:2898472-Immunoassay, pubmed-meshheading:2898472-Light, pubmed-meshheading:2898472-Molecular Sequence Data, pubmed-meshheading:2898472-Plants, Medicinal, pubmed-meshheading:2898472-Protein Biosynthesis, pubmed-meshheading:2898472-Protein Precursors, pubmed-meshheading:2898472-RNA, Messenger, pubmed-meshheading:2898472-Sequence Homology, Nucleic Acid
pubmed:year
1988
pubmed:articleTitle
Chloroplast and cytosolic glutamine synthetase are encoded by homologous nuclear genes which are differentially expressed in vivo.
pubmed:affiliation
Laboratory of Plant Molecular Biology, Rockefeller University, New York, New York 10021-6399.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't