Nuclear factors binding to the mini-exon repeat of Trypanosoma brucei.
In trypanosomes and related kinetoplastida a common short 5' leader sequence is encoded by the highly repetitive mini-exon gene and added to all protein coding mRNAs by trans-splicing. To initiate a search for transcription factors associated with transcription of the mini-exon we have used an electrophoretic mobility shift assay to detect trypanosome nuclear factors which interact specifically with mini-exon DNA. A factor present in the nuclei of both infectious bloodstream forms and non-infectious culture forms of Trypanosoma brucei was shown by DNAase I footprinting and oligonucleotide competition to bind 5' to the transcription start site of the mini-exon. A second factor which bound to the mini-exon itself at a sequence conserved in other kinetoplastida was evident only in the nuclei of infectious bloodstream forms.
Koronakis
V E
VE
Department of Pathology, Cambridge University, U.K.
Ross
A M
AM
Le Page
R W
RW
Hughes
C
C
D000818:Animals; D001345:Autoradiography; D001667:Binding, Competitive; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004274:DNA, Recombinant; D004268:DNA-Binding Proteins / Q000032:analysis; D003850:Deoxyribonuclease I; D004591:Electrophoresis, Polyacrylamide Gel; D005091:Exons; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000032:analysis / Q000502:physiology; D012091:Repetitive Sequences, Nucleic Acid; D014157:Transcription Factors / Q000032:analysis*; D014346:Trypanosoma brucei brucei / Q000235:genetics*
D004274:DNA, Recombinant; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D014157:Transcription Factors; D003850:Deoxyribonuclease I