Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
21
pubmed:dateCreated
2007-7-2
pubmed:abstractText
The functions of centrosomal protein ninein may be involved in microtubule minus end capping, centriole positioning, protein anchoring and microtubule nucleation, but the true physiological function of various human hNinein isoforms remains to be determined. Here we describe the identification of four diverse CCII-termini of human hNinein isoforms, including a novel isoform 6, by differential expression in a tissue-specific manner. These hNinein isoforms exhibit centrosomal (concentrated) and noncentrosomal (aggregated) localization when GFP-tagged fusion proteins are expressed transiently in mammalian cells. In a kinase assay, we show that the CCII region of hNinein provides a differential phosphorylation site by GSK3beta. In addition, our data indicate that either N-terminal or CCIIZ domain disruption may cause hNinein conformational change which recruits gamma-tubulin to centrosomal or noncentrosomal hNinein-containing sites, implying that the gamma-tubulin localization may be hNinein-dependent. Further, our RNA interference experiment against all hNinein isoforms caused a significant decrease in the gamma-tubulin signal in the centrosome. In domain swapping, we clearly show that the CCIIX-CCIIY region provides docking sites for gamma-tubulin. Moreover, our data also show that nucleation of microtubules from the centrosome is significantly affected by the presence of either the full -length hNinein or CCIIX-CCIIY region overexpression. Taken together, these results show that the centrosomal targeting signals of hNinein have a role not only in regulating hNinein conformation, resulting in localization change, but also provide docking sites to recruit gamma-tubulin at centrosomal and noncentrosomal sites.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1551-4005
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
5
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2517-27
pubmed:dateRevised
2011-11-2
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Characterization and functional aspects of human ninein isoforms that regulated by centrosomal targeting signals and evidence for docking sites to direct gamma-tubulin.
pubmed:affiliation
Graduate Institute of Biochemistry, Kaosiung Medical University, Kaohsiung, Taiwan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't