title: Alternative splicing generates a diacylglycerol kinase α transcript that acts as a dominant-negative modulator of superoxide production in localized aggressive periodontitis.
abstract: BACKGROUND
  Diacylglycerol (DAG), levels of which are tightly regulated by diacylglycerol kinases (DGKs), is a lipid mediator linked to key biologic functions. Members of the DGK family undergo alternative splicing, generating the protein diversity necessary to control different intracellular DAG pools. DGKα function is altered in polymorphonuclear neutrophils (PMNs) of patients with localized aggressive periodontitis (LAgP), suggesting a genetic basis. Here, the authors assess DGKα spliced transcripts in human LAgP neutrophils.
  
  
  METHODS
  In an expression library of a patient with LAgP, PMNs were screened for different DGKα transcripts. Real-time polymerase chain reaction and in vitro expression assays were performed to assess the fate of different transcripts on protein translocation and superoxide production in human leukemia cells (HL-60) and COS-7 cells.
  
  
  RESULTS
  A DGKα transcript that lacks exon 10 (DGKαΔ10) and generates a premature stop codon and a truncated protein was identified as being upregulated in LAgP neutrophils. In vitro assays revealed that DGKαΔ10 translocation occurred even in the absence of important regulatory motifs. Transfection of HL-60 neutrophil-like cells with the DGKαΔ10 spliced variant induced an increase in the stimulated production of superoxide anion replicating the phenotype of LAgP PMNs.
  
  
  CONCLUSIONS
  DGKαΔ10 can act as a dominant-negative transcript that can modulate superoxide production and provides an example of genetic regulation of the inflammatory response that may be relevant to human inflammatory diseases such as LAgP.
authors.affiliation: Department of Diagnostics and Surgical Sciences and Department of Oral Biology, Faculty of Dentistry, University of Manitoba, Winnipeg, MB, Canada; previously, Department of Periodontology and Oral Biology, Boston University Goldman School of Dental Medicine, Boston, MA.
authors.forename: Eraldo L
authors.initials: EL
authors.lastname: Batista
authors.forename: Alpdogan I
authors.initials: AI
authors.lastname: Kantarci
authors.forename: Hatice
authors.initials: H
authors.lastname: Hasturk
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Van Dyke
mesh_terms: D000328:Adult; D010520:Aggressive Periodontitis / Q000097:blood* / Q000235:genetics; D017398:Alternative Splicing / Q000235:genetics*; D020816:Amino Acid Motifs / Q000235:genetics; D000818:Animals; D019556:COS Cells; D016022:Case-Control Studies; D002522:Chlorocebus aethiops; D018389:Codon, Nonsense / Q000235:genetics; D017124:Conserved Sequence / Q000235:genetics; D019852:Diacylglycerol Kinase / Q000235:genetics*; D005091:Exons / Q000235:genetics; D005260:Female; D018922:HL-60 Cells; D006801:Humans; D008297:Male; D009504:Neutrophils / Q000201:enzymology; D020033:Protein Isoforms / Q000235:genetics; D012322:RNA Precursors / Q000235:genetics*; D013481:Superoxides / Q000378:metabolism*; D014162:Transfection
chemical_list: D018389:Codon, Nonsense; D020033:Protein Isoforms; D012322:RNA Precursors; D013481:Superoxides; D019852:Diacylglycerol Kinase
keywords: Aggressive periodontitis; diacylglycerol kinase; inflammation; neutrophils; phosphoprotein phosphatases; protein kinases