MyoD is a bHLH transcription factor which, when expressed in a variety of cell types, converts those cells into muscle. E12 is also a bHLH transcription factor that can bind to similar sequences as MyoD, yet cannot activate muscle specific transcription. Only 3 residues from the MyoD basic region, when placed into E12, converts E12 into a myogenic activator without effecting DNA binding. Similarly, extensive mutagenesis of one of these residues in MyoD (ala-114) leads to a class of """"""""positive control"""""""" mutants -- molecules that bind normally, but fail to activate. The primary goal of this proposal is to focus on the nature of this myogenic specificity by determining: (1) whether the positive control mutants bind to target sequences in vivo; (2) what cellular factors """"""""recognize"""""""" the basic region """"""""myogenic code""""""""; (3) the 3-d structure of MyoD and MyoD-El2 heterodimers bound to DNA and in solution; (4) the rules for HLH dimerization efficiency; (5) the rules for how the basic region determines a preferred DNA binding site.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Unknown (R35)
Project #
5R35CA042506-09
Application #
2090772
Study Section
Special Emphasis Panel (SRC (88))
Project Start
1986-06-01
Project End
2000-03-31
Budget Start
1994-06-01
Budget End
1995-03-31
Support Year
9
Fiscal Year
1994
Total Cost
Indirect Cost
Name
Fred Hutchinson Cancer Research Center
Department
Type
DUNS #
075524595
City
Seattle
State
WA
Country
United States
Zip Code
98109
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