David Judah

Date of Award


Degree Type


Degree Name

Master of Science


Pharmacology and Toxicology


Dr. Lina Dagnino


In human keratinocytes and other cell types, the E2F family of transcription factors is primarily responsible for the initiation of cell progression from G1 to S-phase of the cell cycle. Topreventunregulatedproliferation,E2Fsarerepressedbyretinoblastoma protein (pRB) and ErbB3 Binding Protein 1 (EBP1). Previously, chromatin immunoprecipitation (ChIP) assays preformed in our laboratory have identified the proximal region of the EBP1 gene as a putative target of E2F1, 3, 4 and 5. Therefore I hypothesize that E2F directly binds the EBP1 promoter to activate its expression.

Luciferase reporter assays utilizing selected regions of the EBP1 promoter identified the -170 to -100 region relative to the transcription start site as containing elements necessary for the transcription of the EBP1 gene. Electrophoretic mobility shift assays (EMSA) of the -170 to -100 region identified two sites where E2F1 can bind. This binding was comparable to the binding exhibited by E2F to promoters of genes like N-myc and TIMELESS. Additionally, mutation of these sites abolished binding by E2F1 and decreased transcriptional activity of the EBP1 promoter. Furthermore, these sites were shown to act in concert to activate transcription together and that only when both were mutated did transcription decrease significantly. The sites also showed little similarity to

the established E2F consensus site (5'-TTTSSCGC- 3'). These studies confirm that E2F binds to the EBP1 promoter through non-consensus E2F sites and activates its transcription.


Further characterization of the E2F sites within the EBP1 promoter will allow for a new perspective of both the binding properties as well as the transcriptional activating properties of E2F.



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.