Structural and functional analysis of domains mediating interaction between NKX-3.1 and PDEF.
NKX-3.1 is a suspected prostate tumor suppressor gene that encodes a homeodomain transcription factor. NKX-3.1 has been demonstrated to interact with prostate derived Ets factor (PDEF) and to suppress the ability of PDEF to transactivate the prostate specific antigen promoter. To dissect the molecular basis of the interaction between these transcription factors, deletion analyses were preformed using the yeast two-hybrid system. The interaction of NKX-3.1 with full-length PDEF requires part of the homeodomain and a tyrosine-rich 21 amino acid sequence that lies C-terminal to the homeodomain. The interaction of PDEF with full-length NKX-3.1 requires the Ets domain and a linker region that lies between the Ets and pointed domains. Deletion of the C-terminal 21 amino acids of NKX-3.1 completely disrupts the ability to suppress the transactivation function of PDEF in prostate tumor cells, demonstrating concordance between interaction in yeast and function in mammalian cells. These studies have identified novel protein-protein interaction domains within NKX-3.1 and PDEF that operate in concert with their respective DNA binding domains to mediate functional interactions between these growth regulatory transcription factors.
Chen
Hui
H
Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland 21250, USA.
Bieberich
Charles J
CJ
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D045744:Cell Line, Tumor; D017931:DNA Primers; D024202:Electrophoretic Mobility Shift Assay; D005455:Fluorescent Antibody Technique; D018398:Homeodomain Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D006801:Humans; D008297:Male; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D050783:Proto-Oncogene Proteins c-ets; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
D017931:DNA Primers; D018398:Homeodomain Proteins; C491178:NKX3-1 protein, human; D050783:Proto-Oncogene Proteins c-ets; D011994:Recombinant Proteins; C403974:SPDEF protein, human; D014157:Transcription Factors