Morii E, Takebayashi K, Motohashi H, Yamamoto M, Nomura S, Kitamura Y
Department of Pathology, Osaka University Medical School, Japan.
Biochem Biophys Res Commun. 1994 Dec 15;205(2):1299-304. doi: 10.1006/bbrc.1994.2806.
The mi locus of mice encodes a novel member of the basic-helix-loop-helix-leucine zipper protein family of transcription factors (MITF). Mutant mice of the mi/mi genotype have the deletion of an arginine in the basic domain and show the abnormality in development of eyes, melanocytes, osteoclasts and mast cells. The expression of the mast cell protease 6 (MMCP-6) gene is markedly reduced in mi/mi mice. We examined the in vitro binding ability of the normal and mutant MITF to a hexameric motif (CACATG) located in the 5'-flanking sequence of the MMCP-6 gene. The normal MITF bound the hexameric motif but the mutant MITF did not, suggesting that the MITF directly regulated the expression of the MMCP-6 gene.
小鼠的mi基因座编码一种转录因子碱性螺旋-环-螺旋-亮氨酸拉链蛋白家族的新成员（MITF）。mi/mi基因型的突变小鼠在碱性结构域缺失一个精氨酸，并在眼睛、黑素细胞、破骨细胞和肥大细胞的发育中表现出异常。肥大细胞蛋白酶6（MMCP-6）基因在mi/mi小鼠中的表达明显降低。我们检测了正常和突变型MITF与位于MMCP-6基因5'侧翼序列中的六聚体基序（CACATG）的体外结合能力。正常的MITF能结合该六聚体基序，而突变型MITF则不能，这表明MITF直接调控MMCP-6基因的表达。
