https://scholars.lib.ntu.edu.tw/handle/123456789/186488
標題: | Involvement of Multiple DNA Elements in Iron-Inducible Transcription of the Ap65-1 Gene in the Protozoan Parasite Trichomonas Vaginalis | 作者: | ONG, SHIOU-JENG LIU, HSING-WEI TAI, JUNG-HSIANG |
公開日期: | 2004 | 卷: | v.52 | 期: | n.6 | 起(迄)頁: | 1721-1730 | 來源出版物: | MOLECULAR MICROBIOLOGY | 摘要: | A reputed iron-responsive region, which contains multiple nuclear protein -binding DNA sequences, was shown previously to regulate iron-inducible transcription of the ap65-1 gene in the protozoan pathogen, Trichomonas vaginalis. These DNA sequences include two overlapping MYB recognition elements ( MRE-1/MRE-2r) and three abutted T-tract elements. Additional nuclear protein-binding DNA sequences flanking the 5' ( AGTGAAGTGA) and 3' (MRE-2f) of the iron-responsive region were identified in the present study. A stable promoter assay and primer extension revealed that transcriptional activity of the ap65-1 promoter is iron inducible as well as growth related, being lowest in the early logarithmic phase and highest in the mid-logarithmic phase. Subsequent mutational analysis of individual DNA elements of the ap65-1 promoter suggests that closely spaced T-tract elements together with an intervening GAAGGAAG sequence within the iron-responsive region are most critical for regulation of overall transcriptional activity, whereas an additional AGTGAAGTGA and MRE -2f together with an upstream T-rich region are required for optimal iron- inducible activity, and the MRE-1/MRE-2r overlap is only involved in growth-related activity. These observations suggest that expression of the ap65-1 gene is dynamically regulated under various growth conditions via interactions among multiple DNA regulatory elements. |
URI: | http://ntur.lib.ntu.edu.tw//handle/246246/89211 |
顯示於: | 醫學系 |
在 IR 系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。