Linked Life Data

16897480

Source:http://linkedlifedata.com/resource/pubmed/id/16897480

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4-5
pubmed:dateCreated
2006-8-9
pubmed:abstractText
In bacterial and animal coenzyme A (CoA) biosynthesis, pantothenate kinase (PANK) activity is critical in regulating intracellular CoA levels. Less is known about the role of PANK in plants, although a single plant isozyme from Arabidopsis, AtPANK1, was previously cloned and analyzed in vitro. We report here the characterization of a second pantothenate kinase of Arabidopsis, AtPANK2, as well as characterization of the physiological roles of both plant enzymes. The activity of the second pantothenate kinase, AtPANK2, was confirmed by its ability to complement the temperature-sensitive mutation of the bacterial pantothenate kinase in E. coli strain ts9. Knock-out mutation of either AtPANK1 or AtPANK2 did not inhibit plant growth, whereas pank1-1/pank2-1 double knockout mutations were embryo lethal. The phenotypes of the mutant plants demonstrated that only one of the AtPANK enzymes is necessary and sufficient for producing adequate CoA levels, and that no other enzyme can compensate for the loss of both isoforms. Real-time PCR measurements of AtPANK1 and AtPANK2 transcripts indicated that both enzymes are expressed with similar patterns in all tissues examined, further suggesting that AtPANK1 and AtPANK2 have complementary roles. The two enzymes have homologous pantothenate kinase domains, but AtPANK2 also carries a large C-terminal protein domain. Sequence comparisons indicate that this type of "bifunctional" pantothenate kinase is conserved in other higher eukaryotes as well. Although the function of the C-terminal domain is not known, homology structure modeling suggests it contains a highly conserved cluster of charged residues that likely constitute a metal-binding site.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0167-4412
pubmed:author
pubmed:issnType
Print
pubmed:volume
61
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
629-42
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:16897480-Amino Acid Sequence, pubmed-meshheading:16897480-Arabidopsis, pubmed-meshheading:16897480-Arabidopsis Proteins, pubmed-meshheading:16897480-Cloning, Molecular, pubmed-meshheading:16897480-Coenzyme A, pubmed-meshheading:16897480-DNA, Bacterial, pubmed-meshheading:16897480-Gene Expression Regulation, Enzymologic, pubmed-meshheading:16897480-Gene Expression Regulation, Plant, pubmed-meshheading:16897480-Genetic Complementation Test, pubmed-meshheading:16897480-Humans, pubmed-meshheading:16897480-Models, Molecular, pubmed-meshheading:16897480-Molecular Sequence Data, pubmed-meshheading:16897480-Mutation, pubmed-meshheading:16897480-Phosphotransferases (Alcohol Group Acceptor), pubmed-meshheading:16897480-Plant Leaves, pubmed-meshheading:16897480-Plant Oils, pubmed-meshheading:16897480-Protein Conformation, pubmed-meshheading:16897480-RNA, Messenger, pubmed-meshheading:16897480-RNA, Plant
pubmed:year
2006
pubmed:articleTitle
Plant coenzyme A biosynthesis: characterization of two pantothenate kinases from Arabidopsis.
pubmed:affiliation
Plant Biology Department, Michigan State University, East Lansing, MI 48824-6340, USA. tilton@msu.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.