Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1996-12-5
pubmed:abstractText
A monospecific autoimmune serum for poly(ADP-ribosyl)transferase (pADPRT) was used to localise the enzyme in ultrastructural cellular compartments. We detected enzyme in mitochondria of HeLa and Sertoli cells. Within the nucleoplasm the enzyme concentration was positively correlated with the degree of chromatin condensation, with interchromatin spaces being virtually free of pADPRT. During spermatogenesis we observed a gradual increase of the chromatin associated pADPRT that parallelled chromatin condensation. The highest concentration was seen in the late stages of sperm differentiation, indicating the existence of a storage form in transcriptionally inactive nuclei. In nucleoli pADPRT is accumulated in foci within the dense fibrillar component. Such foci are seen in close spatial relationship to sites of nucleolar transcription as revealed by high resolution immunodetection of bromouridine uptake sites. It is suggested that nucleolar pADPRT plays a role in preribosome processing via the modification of nucleolus specific proteins that bind to nascent transcripts and hence indirectly regulates polymerase I activity. The persisting binding of pADPRT to ribonucleoproteins may explain the observed disperse enzyme distribution at lower concentrations in the granular component. The fibrillar centres seem to contain no pADPRT. We conclude that known compounds of fibrillar centres like polymerase I are unlikely candidates for modification via direct covalent ADP-ribosylation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9533
pubmed:author
pubmed:issnType
Print
pubmed:volume
109 ( Pt 2)
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
409-18
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Nuclear architecture and ultrastructural distribution of poly(ADP-ribosyl)transferase, a multifunctional enzyme.
pubmed:affiliation
Institute of Histology and Embryology, University of Vienna, Austria.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't