Glucose dependent [correction of dependant] negative translational control of the heterologous expression of the preS2 HBV antigen in yeast.
In the present study, we have compared the expression level of the genes encoding the viral Hepatitis B S and preS2 using two different yeast vectors, a constitutive one (YepIPT) and a galactose-inducible one (YepDP1-8). We showed that the S and preS2 mRNAs were present in equivalent amounts in both systems, while the corresponding proteins showed a different pattern. The S and preS2 proteins were efficiently produced after galactose induction. However, under the constitutive promoter, the S protein was synthesized at the same level in presence of 2% glucose or galactose whereas the preS2 protein was efficiently synthesized on galactose but absent on 2% glucose. The substitution of glucose by non-repressive carbon sources such as 2% galactose, ethanol or glycerol led to a significant expression of preS2. A high level of preS2 expression was also achieved by lowering the glucose concentration. Our data suggest that glucose exerts a concentration dependent negative translational control on the preS2 mRNA.
Borchani-Chabchoub
Istabrak
I
Laboratoire de Génétique Moléculaire des Eucaryotes, Centre de Biotechnologie de Sfax, BP K 3038, Sfax, Tunisia.
Mokdad-Gargouri
Raja
R
Gargouri
Ali
A
D015152:Blotting, Northern; D015153:Blotting, Western; D005656:Fungal Proteins / Q000235:genetics; D005690:Galactose / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D005822:Genetic Vectors / Q000235:genetics; D005947:Glucose / Q000494:pharmacology*; D006514:Hepatitis B Surface Antigens / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D014176:Protein Biosynthesis / Q000235:genetics*; D011498:Protein Precursors / Q000235:genetics*; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics*
D005656:Fungal Proteins; D006514:Hepatitis B Surface Antigens; D011498:Protein Precursors; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; C050807:presurface protein 2, hepatitis B surface antigen; D005947:Glucose; D005690:Galactose