Characterization of rat serum amyloid A4 (SAA4): A novel member of the SAA superfamily

Christine Rossmann, Christian Windpassinger, Daniela Brunner, Alenka Kovacevic, Natascha Schweighofer, Roland Malli, Rufina Schuligoi, Andreas Prokesch, Barbara Kluve-Beckerman, Wolfgang F. Graier, Dagmar Kratky, Wolfgang Sattler, Ernst Malle*

*Korrespondierende/r Autor/-in für diese Arbeit

Publikation: Beitrag in einer FachzeitschriftArtikelBegutachtung

Abstract

The serum amyloid A (SAA) family of proteins is encoded by multiple genes, which display allelic variation and a high degree of homology in mammals. The SAA1/2 genes code for non-glycosylated acute-phase SAA1/2 proteins, that may increase up to 1000-fold during inflammation. The SAA4 gene, well characterized in humans (hSAA4) and mice (mSaa4) codes for a SAA4 protein that is glycosylated only in humans. We here report on a previously uncharacterized SAA4 gene (rSAA4) and its product in Rattus norvegicus, the only mammalian species known not to express acute-phase SAA. The exon/intron organization of rSAA4 is similar to that reported for hSAA4 and mSaa4. By performing 5′- and 3′RACE, we identified a 1830-bases containing rSAA4 mRNA (including a GA-dinucleotide tandem repeat). Highest rSAA4 mRNA expression was detected in rat liver. In McA-RH7777 rat hepatoma cells, rSAA4 transcription was significantly upregulated in response to LPS and IL-6 while IL-1α/β and TNFα were without effect. Luciferase assays with promoter-truncation constructs identified three proximal C/EBP-elements that mediate expression of rSAA4 in McA-RH7777 cells. In line with sequence prediction a 14-kDa non-glycosylated SAA4 protein is abundantly expressed in rat liver. Fluorescence microscopy revealed predominant localization of rSAA4-GFP-tagged fusion protein in the ER.

Originalspracheenglisch
Seiten (von - bis)1643-1649
Seitenumfang7
FachzeitschriftBiochemical and Biophysical Research Communications
Jahrgang450
Ausgabenummer4
DOIs
PublikationsstatusVeröffentlicht - 8 Aug. 2014

ASJC Scopus subject areas

  • Biophysik
  • Biochemie
  • Molekularbiologie
  • Zellbiologie

Fields of Expertise

  • Human- & Biotechnology

Treatment code (Nähere Zuordnung)

  • Basic - Fundamental (Grundlagenforschung)
  • Experimental

Fingerprint

Untersuchen Sie die Forschungsthemen von „Characterization of rat serum amyloid A4 (SAA4): A novel member of the SAA superfamily“. Zusammen bilden sie einen einzigartigen Fingerprint.

Dieses zitieren