You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["RNA", "CellLine", "Protein", "DNA", "CellType"].

Please return the output as a JSON object of the format: {"DNA" : ["TAL1", ...], "RNA": ["mRNAs", ...], "CellLine": ["T cells", ...], "CellType": ["monocytes", ...], "Protein": ["IL-2", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

cAMP-dependent regulation of proenkephalin by JunD and JunB: positive and negative effects of AP-1 proteins. We demonstrate that JunD, a component of the AP-1 transcription factor complex, activates transcription of the human proenkephalin gene in a fashion that is completely dependent upon the cAMP-dependent protein kinase, protein kinase A. Activation of proenkephalin transcription by JunD is dependent upon a previously characterized cAMP -, phorbol ester -, and Ca (2 +) -inducible enhancer, and JunD is shown to bind the enhancer as a homodimer. Another component of the AP-1 transcription complex, JunB, is shown to inhibit activation mediated by JunD. As a homodimer JunB is unable to bind the enhancer; however in the presence of c-Fos, high-affinity binding is observed. Furthermore, JunD is shown to activate transcription of genes linked to both cAMP and phorbol ester response elements in a protein kinase A-dependent fashion, further blurring the distinction between these response elements. These results demonstrate that the transcriptional activity of an AP-1-related protein is regulated by the cAMP-dependent second-messenger pathway and suggest that JunD and other AP-1-related proteins may play an important role in the regulation of gene expression by cAMP-dependent intracellular signaling pathways.
{"CellLine": [], "CellType": [], "DNA": ["the human proenkephalin gene", "enhancer", "response elements", "human proenkephalin gene", "cAMP - , phorbol ester - , and Ca (2 +) - inducible enhancer"], "Protein": ["AP - 1 transcription complex", "AP - 1 - related proteins", "protein kinase A", "AP - 1 - related protein", "AP - 1 proteins", "other AP - 1 - related proteins", "AP - 1 transcription factor complex", "cAMP - dependent protein kinase", "a homodimer JunB", "JunB", "c - Fos", "homodimer", "JunD"], "RNA": []}