Vasculin, a novel vascular protein differentially expressed in human atherogenesis.
Recent suppressive subtractive hybridization analysis on human atherosclerotic plaque-derived RNA revealed genes upregulated in plaques with a thrombus versus stable plaques. Clone SSH6, containing part of a putative open reading frame of an unknown protein, was further investigated. Full-length cDNA, coding for a 473-amino acid (aa) protein, was identified in a vascular smooth muscle cell (SMC) cDNA library. Bioinformatics suggested the presence of multiple SSH6 variants due to alternative splicing of exon 3. Multiple-tissue Northern blot analysis demonstrated a differential expression pattern of these variants, as a ubiquitously expressed SSH6 mRNA missing exon 3, was detected apart from a putative vascular SMC-specific form containing exon 3. Western blot analysis indicated a ubiquitous 35-kDa protein (SSH6-beta), in addition to a 45-kDa protein (vasculin), detected in the vascular wall and in plasma. Analysis of arteries displaying various stages of atherosclerosis indicated that the vasculin/SSH6-beta ratio increases throughout atherogenesis. Immunohistochemical analysis demonstrated cytoplasmic expression of SSH6 gene products in macrophages, endothelial cells, and SMCs. In summary, we identified a novel mRNA/protein, vasculin, in the arterial wall and plasma. The regulated expression of vasculin in plaques suggests a role in atherogenesis. Moreover, its presence in plasma opens perspectives for vasculin as a marker for atherosclerosis.
Bijnens
Ann P J J
AP
Department of Pathology, Cardiovascular Research Institute Maastricht, University of Maastricht, The Netherlands.
Gils
Ann
A
Jutten
Barry
B
Faber
Birgit C G
BC
Heeneman
Sylvia
S
Kitslaar
Peter J E H M
PJ
Tordoir
Jan H M
JH
de Vries
Carlie J M
CJ
Kroon
Abraham A
AA
Daemen
Mat J A P
MJ
Cleutjens
Kitty B J M
KB
D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D001161:Arteriosclerosis / Q000378:metabolism*; D001483:Base Sequence; D001798:Blood Proteins / Q000096:biosynthesis* / Q000502:physiology*; D015152:Blotting, Northern; D015153:Blotting, Western; D002460:Cell Line; D002478:Cells, Cultured; D018076:DNA, Complementary / Q000378:metabolism; D004268:DNA-Binding Proteins; D015180:Electrophoresis, Gel, Two-Dimensional; D005091:Exons; D015723:Gene Library; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D007128:Immunoglobulin Fragments / Q000378:metabolism; D007150:Immunohistochemistry; D007438:Introns; D008969:Molecular Sequence Data; D019151:Peptide Library; D010957:Plasmids / Q000378:metabolism; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D012549:Schistosoma japonicum / Q000378:metabolism; D014018:Tissue Distribution
D001798:Blood Proteins; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; C478882:GPBP1 protein, human; D007128:Immunoglobulin Fragments; D019151:Peptide Library; D012333:RNA, Messenger; D011994:Recombinant Proteins; D005982:Glutathione Transferase