Effect of Transcription Terminators on Expression of Human Lipocortin-1 in Recombinant Saccharomyces cerevisiae

다국어 초록 (Multilingual Abstract)

The vector systems for the expression and secretion of human lipocortin-1 (LC1) from Saccharomyces cerevisiae were constructed with GAL10 promoter and the prepro leader sequence of mating factor-αl. They were further constructed to contain three different transcription terminators; GAL7 terminator, LC1 terminator and a fused form of these two terminators. The expression and secretion levels of LC1 were compared to investigate the effect of transcription terminators on the LC1 gene expression. For the expression cassettes employing the GAL7 terminator or the terminator of fused form, the expression levels of LC1 were measured by scanning the immunoreactive LC1 protein bands, and were found to be 0.27g/ℓ and 0.32g/ℓ, respectively. The highest expression level of 0.54g/ℓ was obtained with the expression vector containing the LC1 transcription terminator. In all expression cassettes, the majority of LC1 proteins expressed were retained intracellularly, indicating a low secretion efficiency of about 5%. The high expression level of LC1 was explained by the great content and stability of LC1 mRNA transcribed from the LC1 terminator-employing vector. The results of this study demonstrate that the LC1 transcription terminator functions for the expression of LC1 in S. cerevisiae better than the GAL7 terminator.