Enhancement of the human factor IX expression, mediated by an intron derived fragment from the rat aldolase B gene in cultured hepatoma cells.
Combinations of a liver-specific rat aldolase B intronic enhancer (rABE) with either of the hepatocyte-specific human α1-antitrypsin promoter (hAATp) and cytomegalovirus enhancer/promoter (CMVp) were used to construct a number of plasmids expressing non-viral human factor IX (hFIX). The efficacies of the plasmids were evaluated in a hepatocyte cell line (HepG2). Potential of the rABE was evidenced, by 300%--and 800% increase of the hFIX expression levels when it was combined with the CMVp and hAATp, respectively. The highest hFIX expression level was obtained when the rABE was combined with the CMVp for which the maximum intracellular accumulation of hFIX was also evidenced. Therefore, the rABE is suggested as a suitable cis-acting element for protein expression in hepatocytes. Considering the potential of introns during post-transcriptional processes, the function of the human β-globin (hBG) intron-II, within the hFIX coding region, in the second generations of the hFIX expressing plasmids was also examined, which leaded to reduction of the hFIX expression level, probably due to improper splicing of the hBG intron-II.
Sam
Mohammad Reza
MR
Department of Molecular Genetics, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran.
Zomorodipour
Alireza
A
Shokrgozar
Mohammad Ali
MA
Ataei
Fariba
F
Haddad-Mashadrizeh
Aliakbar
A
Amanzadeh
Amir
A
D000818:Animals; D001709:Biotechnology / Q000379:methods*; D002460:Cell Line; D003587:Cytomegalovirus / Q000235:genetics; D005164:Factor IX / Q000096:biosynthesis* / Q000235:genetics; D005634:Fructose-Bisphosphate Aldolase / Q000235:genetics; D015870:Gene Expression; D022781:Hepatocytes / Q000378:metabolism*; D006801:Humans; D007438:Introns; D010957:Plasmids; D011401:Promoter Regions, Genetic; D051381:Rats; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics; D000515:alpha 1-Antitrypsin / Q000235:genetics
D011994:Recombinant Proteins; D000515:alpha 1-Antitrypsin; D005164:Factor IX; D005634:Fructose-Bisphosphate Aldolase