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:

v-erbA overexpression is required to extinguish c-erbA function in erythroid cell differentiation and regulation of the erbA target gene CAII. The v-erbA oncoprotein represents a retrovirus-transduced oncogenic version of the thyroid hormone (T3 / T4) receptor c-erbA (type alpha). It contributes to virus-induced erythroleukemia by efficiently arresting differentiation of red cell progenitors and by suppressing transcription of erythrocyte-specific genes. Here, we show that v-erbA and c-erbA bind directly to sequences within the promoter of the erythrocyte-specific carbonic anhydrase II (CAII), a gene whose transcription is efficiently suppressed by v-erbA. This erbA-binding site confers thyroid hormone responsiveness to a heterologous promoter in transient expression experiments and is a target for efficient down-regulation of CAII transcription by the v-erbA oncoprotein. In stably transformed erythroblasts coexpressing the v-erbA oncoprotein and the c-erbA / T3 receptor at an approximately equimolar ratio, c-erbA activity is dominant over v-erbA. T3 efficiently induced erythroid differentiation in these cells, thus overcoming the v-erbA-mediated differentiation arrest. Likewise, T3 activated CAII transcription as well as transient expression of a T3-responsive reporter gene containing the CAII-specific erbA-binding site. The c-erbA-dependent activation of this CAII reporter construct could only be suppressed by very high amounts of v-erbA. Our results suggest that overexpression of v-erbA is required for its function as an oncoprotein.
{"CellLine": ["stably transformed erythroblasts"], "CellType": ["erythroid cell", "red cell progenitors"], "DNA": ["heterologous promoter", "erbA - binding site", "erbA target gene", "promoter", "T3 - responsive reporter gene", "CAII", "CAII - specific erbA - binding site", "CAII reporter construct", "erythrocyte - specific genes"], "Protein": ["oncoprotein", "c - erbA (type alpha)", "v - erbA", "T3", "c - erbA / T3 receptor", "erythrocyte - specific carbonic anhydrase II", "v - erbA oncoprotein", "c - erbA", "thyroid hormone (T3 / T4) receptor", "an oncoprotein"], "RNA": []}