陰道滴蟲為一厭氧且具鞭毛的寄生性單細胞動物，它會造成人類的陰道滴蟲病，此一疾病為世界最普遍的非病毒的性感染疾病。目前已發現黏附蛋白參與其中的細胞黏附作用是其引發疾病的關鍵。ap65-1基因是一各分子量為65道爾吞的蛋白，同時也是黏附蛋白(ap65)家族的一員。目前，再陰道滴蟲內的Myb1和Myb2被認為是調控ap65-1轉錄的新因子。MRE-1/MRE-2r和MRE-2f這兩段序列可以被Myb蛋白質所辨識進而調控ap65-1基因的轉錄機制。全長的Myb2蛋白質被發現可以與MRE-1和MRE-2f作用，而胺基酸序列從40到156的截斷蛋白Myb2x保有跟全長Myb2蛋白相似的DNA結合能力。我們利用生物物理的方法來探討截斷蛋白Myb2x與MRE-1和MRE-2f間的相互作用。再者，我們利用NMR的方法決定了Myb2x蛋白的結構和Myb2x蛋白與MRE-1和MRE-2f的複合結構，這些結構可以讓我們了解Myb2/DNA複合結構中的DNA辦識機制。

Trichomonas vaginalis (T. vaginalis), an anaerobic, parasitic flagellated protozoan, is the causative agent of human trichomoniasis, the most common nonviral sexually transmitted infections (STIs) in the world. Cytoadherence, a crucial step for T. vaginalis infection, has been shown to involve multiple surface adhesion proteins. The ap65-1 gene was a member of the ap65 (adhesion protein 65) multigene family encoding multiple homologous 65-kDa proteins. Recently, novel transcription factors, Myb1 and Myb2 proteins, were found to be involved in the transcriptional regulation of ap65-1 gene in T. vaginalis. MRE-1/MRE-2r (which overlap) and MRE-2f, which were found to be the multiple Myb recognition elements, regulate multifarious ap65-1 expression, inferring the involvement of Myb-like transcription factors in the transcription machinery of the parasite.
The full-length Myb2 protein encoded by the myb2 gene was found to interact with specific sequence contexts spanning MRE-1 and MRE-2f. The truncated Myb2 protein, Myb2x, spanning amino acid sequence 40-156, has been found to retain similar DNA binding affinity. We have investigated the interactions of Myb2x protein with MRE-2r and MRE-2f by biophysical methods. Moreover, we have determined the structures and dynamics of Myb2x protein, Myb2x-MRE-2r complex, and Myb2x-MRE-2f complex by NMR. The results allow us to pinpoint the molecular mechanism involved in Myb2/DNA interactions.

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