Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
16
pubmed:dateCreated
2004-4-12
pubmed:databankReference
pubmed:abstractText
Genome sequencing projects have focused attention on the problem of discovering the functions of protein domains that are widely distributed throughout living species but which are, as yet, largely uncharacterized. One such example is the PIN domain, found in eukaryotes, bacteria, and Archaea, and with suggested roles in signaling, RNase editing, and/or nucleotide binding. The first reported crystal structure of a PIN domain (open reading frame PAE2754, derived from the crenarchaeon, Pyrobaculum aerophilum) has been determined to 2.5 A resolution and is presented here. Mapping conserved residues from a multiple sequence alignment onto the structure identifies a putative active site. The discovery of distant structural homology with several exonucleases, including T4 phage RNase H and flap endonuclease (FEN1), further suggests a likely function for PIN domains as Mg2+-dependent exonucleases, a hypothesis that we have confirmed in vitro. The tetrameric structure of PAE2754, with the active sites inside a tunnel, suggests a mechanism for selective cleavage of single-stranded overhangs or flap structures. These results indicate likely DNA or RNA editing roles for prokaryotic PIN domains, which are strikingly numerous in thermophiles, and in organisms such as Mycobacterium tuberculosis. They also support previous hypotheses that eukaryotic PIN domains participate in RNAi and nonsense-mediated RNA degradation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
16
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
16471-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Distant structural homology leads to the functional characterization of an archaeal PIN domain as an exonuclease.
pubmed:affiliation
School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand. v.arcus@auckland.ac.nz
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't