Angotti E, Mele E, Costanzo F, Avvedimento E V
Dipartimento di Medicina Sperimentale e Clinica, Facoltà di Medicina e Chirurgia di Catanzaro, Università degli Studi di Reggio Calabria, Italy.
J Biol Chem. 1994 Jul 1;269(26):17371-4.
AG-->A transition at -78 base pairs from the transcription start site of the apolipoprotein A-I (apoA-I) gene has been associated with increased apoA-I serum levels in humans. We report here that this mutation (G-->A) increases significantly (5-7-fold) the expression of a reporter gene fused to the apoA-I promoter in human liver and intestine cells. In addition, the presence of A at -78 base pairs from the transcription start site of the gene significantly decreases the binding affinity of a nuclear factor present in liver and intestine cells. We suggest that the reduced affinity of this factor increases the transcription efficiency of the promoter and explains why individuals carrying the A allele have high serum apoA-I levels.
载脂蛋白A-I（apoA-I）基因转录起始位点上游78个碱基对处的AG→A转换与人类血清中apoA-I水平升高有关。我们在此报告，这种突变（G→A）可使在人类肝细胞和肠细胞中与apoA-I启动子融合的报告基因的表达显著增加（5至7倍）。此外，基因转录起始位点上游78个碱基对处出现的A可显著降低肝和肠细胞中一种核因子的结合亲和力。我们认为，这种因子亲和力的降低提高了启动子的转录效率，并解释了携带A等位基因的个体血清apoA-I水平较高的原因。
