Molecular analysis of the effects of glucose induction on the transcription of retrotransposon TY2


Thesis Type: Postgraduate

Institution Of The Thesis: Bursa Uludağ University, Fen Bilimleri Enstitüsü, Biyoloji , Turkey

Approval Date: 2007

Thesis Language: Turkish

Student: ELİF ARİK

Supervisor: Sezai Türkel

Abstract:

The yeast retrotranspozon Ty2-917 belongs to retroviridae group and propagates with a retroviral-like mechanism within yeast cells. Ty2-917 has a complex transcriptional regulatory region which contains both activation and repression sites. Ty2 does not encodes any transcription factors and hence its transcriptional regulation is completely depends on the yeast encoded factors. In this study, the effects of glucose signaling on the transcription in the yeast retrotransposon Ty2-917 were analyzed. Growth of S. cerevisiae in glucose or sucrose medium led to a high level of Ty2 transcription. On the contrary, Growth of the yeast cells in glycerol lactate or in ethanol medium resulted in a dramatic decrease in the transcription of Ty2-917. However, when the yeast cells were transferred to a fermentable growth medium, Ty2-917 transcription was activated by 13-fold. In addition, our results indicated that the glucose signaling is exerted through Gcr1p for the activation of Ty2 transcription. Moreover, it was also found that the cyclin Pcl6, which interacts with cyclin dependent protein kinase complex Pho85, is also required for the glucose activation of Ty2. The results of this research demonstrated that the transcription of retroviral-like element Ty2-917 can be regulated in response to metabolic changes within yeast cells.