Prevalence of the 1.8 kb complement factor H mRNA in human lung.
Human complement factor H, described as a 155,000 molecular weight (MW) component, is a key factor in the control of the alternative pathway of complement activation. Using two human factor H cDNA clones, designated R2a (a clone derived from the 3' end of the factor H coding sequence) and B38-1 (a clone derived from the 5' end of the factor H coding sequence), as probes, three factor H-specific transcripts of 4.3 kb, 1.8 kb and 1.5 kb are usually detected in human liver, in equal abundance. Using these two factor H cDNAs to probe human lung RNA, there was evidence of a singular distribution of the factor H mRNA species in human lung compared to liver, in equal prevalence of the 1.8 kb factor H mRNA over the 4.3 kb factor H mRNA (a three- to fourfold difference). No significant expression of the 1.5 kb mRNA was detected. The prevalence of the 1.8 kb complement factor H mRNA leads to the speculation that the predominant factor H form biosynthesized in lung tissue is a truncated form of the factor H molecule.
Demares
M J
MJ
INSERM U78, Bois-Guilleurne, France.
Davrinche
C
C
D015152:Blotting, Northern; D003180:Complement C3b Inactivator Proteins / Q000096:biosynthesis / Q000235:genetics*; D017242:Complement Factor H; D015342:DNA Probes; D006801:Humans; D008099:Liver / Q000032:analysis; D008168:Lung / Q000032:analysis / Q000276:immunology*; D012333:RNA, Messenger / Q000032:analysis*
C493495:CFH protein, human; D003180:Complement C3b Inactivator Proteins; D015342:DNA Probes; D012333:RNA, Messenger; D017242:Complement Factor H