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| | Schematic of NKX2-2 functional domains. The positions of the transcriptional repressor domain (TN), the homeodomain (HD), the NK2-specific domain (SD), and the transcriptional activation domain (TAD) are shown. |
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| Description | 273 amino acids; 30133 Da. NKX2-2 is a member of the NK2 family of homeobox transcription factors. It has known roles in the development of the CNS as well as pancreatic beta cell differentiation. In the CNS NKX2-2 is known to be activated by SHH signaling which is important for its initial role in ventral patterning. NKX2-2 expression has additionally been shown to be critical for the differentiation of oligodendrocytes, and in fact necessary for this process to occur. In both instances, NKX2-2 mediated transcripitional repression is both necessary and sufficient for these processes to occur. Regulation of NKX2-2 expression in the pancreas is less well understood. NKX2-2 knock-out mice die soon after birth from diabetic complications as a result of a lack of fully differentiated pancreatic beta cells. While NKX2-2 mediated transcriptional repression has been demonstrated to be necessary and sufficient for its role in ß-cell differentiation, it remains unclear whether NKX2-2 mediated transcriptional activation is important for NKX2-2 function in adult ß-cells. |
| Expression | V3 neural progenitors; oligodendrocyte precursor cells; precursor and adult pancreatic beta cells. |
| Localisation | Nuclear |
| Function | NKX2-2 is a transcription factor |
| Homology | NKX2-2 shares homology with other members of the NK2 family of transcription factors most notably in the TN transcriptional repression, DNA binding homeodomain, and specific domain regions. |
| Gene fusion with an ETS DNA-binding domain caused by chromosome translocation in human tumours. |
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