CHARACTERIZATION OF A HOMEOBOX-RELATED GENE,ATBF1-ITS POTENTIAL ROLE IN CELL GROWTH AND NEURONAL CELL DIFFERENTLATION AND ANALYSIS OF POLYMORPHISMS IN THE TRIPLET REPEAT REGIONS

同源盒相关基因ATBF1的表征及其在细胞生长和神经细胞分化中的潜在作用以及三联体重复区的多态性分析

• 批准号: 06454611
• 负责人: SHIMA Tomoko
• 金额: $ 2.82万
• 依托单位: HYOGO COLLEGE OF MEDICINE
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06454611/
• 关键词: ATBF1; mouse ATBF1; alternative splicing; neuronal differentiation; granurocytic differentiation; homeodomain; tumorigenesity; triplet repeat; co-transfection; ATBF1遺伝子産物(蛋白); polyclonal抗体

I.The ATBF1 gene was originally isolated from a cDNA library derived from human hepatocellular carcinoma cells (Jpn.J.Electrophoresis). Since the alternative splicing mechanisms during cell differentiation and malignant transformaiton were found in a variety of tumor cell lines (J.Mol.Endocrinol.), we tried to isolate the ATBF1 alternative-spliced isoforms. We found a longer ATBF1-cDNA,ATBF1-A,from a cDNA library derived from human fibroblasts. The cDNA of ATBF1-A is 12kb, encoding a 400kDa protein, while the original ATBF1, now termed ATBF1-B,is 8kb encoding a 300kDa protein. ATBF1-A has 4 homeobox and 23 zinc finger domains and one of the largest gene of the homeodomain-zinc finger gene family, and its expression was highly induced during neuronal differentiation (JBC). We also cloned the mouse ATBF1-A,whose expression is high in the developing brain but low in the adult tissues (Gene). On the other hand, the expression of ATBF1-B was specifically induced during granurocytic differen … More tiation of leukemia cells. Taken together, two isoforms of ATBF1 are independently expressed in a cell specific manner, however, further investigation is needed using other cell lineage.Using rabbit polyclonal antibodies, a 250kDa protein was detected by Western bloting that the ATBF1 protein may be cleaved after transcription. Also, a possibility of dimerization of the ATBF1 at the homeodomains were found.II.The expression vectors of ATBF1 were transfected to NIH-3T3 and PC12 cells. The exogenous ATBF1 was detected just after the transfeciton, but lost after several pasages, indicating that its overexpression reduced cell growth whle non-transfectants could survive. These results suggest that the ATBF1 expression may suppress tumor growth through both growth arrest and cellular differentiation.III.There are several triplet repeat regions in the ATBF1 gene, and 6-10 repeat polymorphism was found at a CAA region. DNAs isolated from patients with several neurodegenerative diseases showed no apparent expansion of this region. The ATBF1 was mapped on chromosome 16q22, however, no linkage has been reported in this region so far. When some diseases will be mapped in this region, more study must be conducted. Less

1 . ATBF1基因最初从人肝癌细胞cDNA文库中分离得到（jpn . j .电泳）。由于在多种肿瘤细胞系中都发现了细胞分化和恶性转化过程中的选择性剪接机制（j.l l. endocrinol .），我们试图分离ATBF1的选择性剪接亚型。我们从人成纤维细胞的cDNA文库中发现了一个较长的ATBF1-cDNA，ATBF1-A。ATBF1- a的cDNA长度为12kb，编码400kDa蛋白，而原ATBF1（现在称为ATBF1- b）的cDNA长度为8kb，编码300kDa蛋白。ATBF1-A具有4个同源结构域和23个锌指结构域，是同源结构域-锌指基因家族中最大的基因之一，其表达在神经元分化（JBC）过程中受到高度诱导。我们还克隆了小鼠ATBF1-A，其在发育中的大脑中表达高，而在成年组织中表达低（基因）。另一方面，ATBF1-B的表达在白血病细胞的粒细胞分化过程中被特异性诱导。综上所述，ATBF1的两种异构体以细胞特异性的方式独立表达，然而，需要使用其他细胞谱系进行进一步研究。利用兔多克隆抗体，Western blotting检测到250kDa的ATBF1蛋白在转录后可能被切割。同时发现ATBF1在同源结构域存在二聚化的可能性。ii .将ATBF1表达载体转染NIH-3T3和PC12细胞。外源的ATBF1在转染后被检测到，但在几代后就消失了，这表明它的过表达降低了细胞的生长，而非转染的细胞可以存活。这些结果表明，ATBF1的表达可能通过抑制肿瘤生长和细胞分化来抑制肿瘤生长。iii . ATBF1基因存在多个三联体重复区域，在一个CAA区域存在6-10个重复多态性。从几种神经退行性疾病患者中分离的dna显示该区域没有明显的扩张。ATBF1基因定位于16q22染色体上，但目前未见该区域连锁的报道。当一些疾病将在该地区绘制地图时，必须进行更多的研究。少

项目成果

Hashimoto,T.,et al.: "Induction of the expression of the ATBF1 gene during differentiation of hematopoetic cells" in preparation.

Hashimoto,T.,et al.：“造血细胞分化过程中 ATBF1 基因表达的诱导”正在准备中。

Miura,Y.,et al.: "Cloning and characterization of an ATBF1 isoform that expresses in a neuronal differentiation-dependent manner" J. Biol. Chem. 270. 26840-26848 (1995)

Miura,Y.,et al.：“以神经元分化依赖性方式表达的 ATBF1 同工型的克隆和表征”J. Biol。

Kodama,A.,et al.: "A new CAA repeat polymorphism in the ATBF1 gene" in preparation.

Kodama,A.,et al.：“ATBF1 基因中的新 CAA 重复多态性”正在准备中。

Nakamura,M.,et al.: "Multiple alternative splice isoforms of parathyroid hormone-related peptide mRNA in human cell lines" J. Mol. Endocrin.15. 245-249 (1995)

Nakamura,M.,et al.：“人类细胞系中甲状旁腺激素相关肽 mRNA 的多种选择性剪接亚型”J. Mol。

Hashimoto, T., et al.: "Induction of the expression of the ATBF1 gene during differentiation of leukemic cell lines." (in preparation).

Hashimoto, T. 等人：“在白血病细胞系分化过程中诱导 ATBF1 基因的表达。”