<qa>  What is the name of the protein encoded by the left end of the human adenTThe 243 amino acid E1A protein also known as small E1A protein, transforming E1A protein encoded by the left end of the human adenovirus Ad type 2 or 5 genome has been studied in various contexts including as a model cooperating oncoprotein, an apoptosis inducing protein, and as a therapeutic oncolytic protein. All of these properties are associated with its capacity to rapidly induce S phase in a variety of cells. E1A orchestrates most of these effects by interacting with an array of chromatin remodeling complexes, including the Rb family proteins, and the HAT proteins p300 and CBP. 