TRANSCRIPTIONAL ACTIVATION BY MYO-D

MYO-D 的转录激活

• 批准号: 2090772
• 负责人: HAROLD M WEINTRAUB
• 金额: $ 70.54万
• 依托单位: FRED HUTCHINSON CANCER RESEARCH CENTER
• 依托单位国家: 美国
• 财政年份: 1986
• 资助国家: 美国
• 起止时间: 1986-06-01 至 2000-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2090772
• 关键词: DNA; DNA footprinting; chemical binding; dimer; gene expression; genetic transcription; molecular site; mutant; myogenesis; nucleic acid sequence; site directed mutagenesis; striated muscles; transcription factor

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.

Myod是BHLH转录因子 各种细胞类型，将这些细胞转换为肌肉。 E12是 也是可以与类似序列结合的BHLH转录因子 作为myod，但无法激活肌肉特定的转录。 仅有的 3个来自Myod基本区域的残基，将其放入E12时， 将E12转换为肌原激活剂而不影响DNA 结合。 同样，这些残基之一的广泛诱变 在Myod（ALA-114）中导致一类“阳性对照”突变体 - 正常结合但无法激活的分子。 主要 该提议的目标是专注于这种肌源性的性质 通过确定特异性：（1）阳性对照是否是否 突变体与体内的靶序列结合； （2）什么细胞因素 “识别“基本区域”“肌源代码”； （3）3-D结构 Myod和Myod-El2异二聚体与DNA和溶液结合； （4） HLH二聚化效率的规则； （5）如何 基本区域确定了首选的DNA结合位点。