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:

Identification and cloning of TCF-1, a T lymphocyte-specific transcription factor containing a sequence-specific HMG box. CD3-epsilon expression is controlled by a downstream T lymphocyte-specific enhancer element. We report the identification of a T cell-specific transcription factor, TCF-1, binding to this element. The multimerized recognition motif of TCF-1 constituted a T cell-specific enhancer. Subsequent cloning of TCF-1 identified three splice alternatives. TCF-1 contained a single DNA-binding HMG box most closely related to similar boxes in the putative mammalian sex-determining gene SRY and in the Schizosaccharomyces pombe Mc mating type gene. TCF-1 mRNA was expressed uniquely in T lymphocytes. Upon cotransfection into non-T cells, TCF-1 could transactivate through its cognate motif. These results identify TCF-1 as a T cell-specific transcription factor, which might play a role in the establishment of the mature T cell phenotype.
{"CellLine": [], "CellType": ["non - T cells", "mature T cell phenotype", "T lymphocytes"], "DNA": ["putative mammalian sex - determining gene", "SRY", "Schizosaccharomyces pombe Mc mating type gene", "downstream T lymphocyte - specific enhancer element"], "Protein": ["T cell - specific transcription factor", "a T cell - specific transcription factor", "splice alternatives", "sequence - specific HMG box", "DNA - binding HMG box", "TCF - 1", "multimerized recognition motif", "T lymphocyte - specific transcription factor", "CD3"], "RNA": ["TCF - 1 mRNA"]}