Alam Tanfis Istiaq, Kanki Tomotake, Muta Tsuyoshi, Ukaji Koutarou, Abe Yoshito, Nakayama Hiroshi, Takio Koji, Hamasaki Naotaka, Kang Dongchon
Department of Clinical Chemistry and Laboratory Medicine, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
Nucleic Acids Res. 2003 Mar 15;31(6):1640-5. doi: 10.1093/nar/gkg251.
Mitochondrial transcription factor A (TFAM), a member of the high mobility group proteins, is essential for maintenance of mitochondrial DNA (mtDNA). Most TFAM and mtDNA (both of which are normally soluble) was recovered from the particulate fraction of human placental mitochondria when extracted with the non-ionic detergent Nonidet P-40. mtDNA and TFAM were co-immunoprecipitated by anti-TFAM antibodies. TFAM was released into the supernatant by DNase I digestion of mtDNA in the particulate fraction. Thus, TFAM and mtDNA are tightly associated with each other, and it is likely that few TFAM or mtDNA molecules exist in an unbound form in mitochondria. Based on the fact that TFAM is abundant enough to wrap mtDNA entirely, these results suggest that human mtDNA is packaged with TFAM.
线粒体转录因子A（TFAM）是高迁移率族蛋白家族的成员之一，对维持线粒体DNA（mtDNA）至关重要。当用非离子去污剂Nonidet P - 40提取时，大部分TFAM和mtDNA（二者通常均为可溶性）是从人胎盘线粒体的颗粒部分回收得到的。mtDNA和TFAM可被抗TFAM抗体共免疫沉淀。通过对颗粒部分中的mtDNA进行DNA酶I消化，TFAM被释放到上清液中。因此，TFAM和mtDNA彼此紧密相连，并且线粒体中可能很少有TFAM或mtDNA分子以未结合的形式存在。基于TFAM含量丰富足以完全包裹mtDNA这一事实，这些结果表明人mtDNA是与TFAM一起包装的。
