Phylogenetic analysis of pigment cell differentiation

色素细胞分化的系统发育分析

• 批准号: 08044186
• 负责人: YAMAMAOTO Hiroaki
• 金额: $ 2.24万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for international Scientific Research
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08044186/
• 关键词: Pigment cell; TRP gene; Tyrosinase gene; Ascidians; Vertebrates; Urochordata; Phylogenitic analysis; microphthalmia gene; ゲノム解析; チロシナーゼ; クローニング; チロシナーゼ関連タンパク質

The main purpose of this project was to analyze phylogenetically the molecular mechanisms of pigment cell differentiation. The first step was to clone ascidian homologues for vertebrate genes involved in differentiation of pigment cells. Then, we analyzed the gene structures from phylogenetic view points. Their expression patterns were also analyzed.We obtained the following results.a. Putative ascidian tyrosinase gene encoding a key enzyme essential for melanin biosynthesis was cloned and their expression patterns were analyzed.b. Putative ascidian tyrosinase-related protein gene was also cloned. This gene showed the very early onset of expression in the course of ascidian development similar to those of vertebrate homologues.c. We identified several cis-acting elements in their regulatory regions.d. Putative ascidian MITF(microphthalmia-associated transcription factor) gene was cloned.Vertebrate MITF is known to activate expression of tyrosinase and its related genes. We had found that MITF-M is an essential isoform to allow differentiation of melanocyte from neural crest cells in vertebrates. Ascidian MITF homologue can not express the M-isoform.e. Ascidian MITF homologue can transactivate both ascidian tyrosinase and tyrosinase-related protein genes but also vertebrate tyrosinase and TRP genes. On the other hand, only one of vertebrate MITF isoforms can transactivate the ascidian TRP gene.

本项目的主要目的是从遗传学角度分析色素细胞分化的分子机制。第一步是克隆与色素细胞分化有关的脊椎动物基因的海鞘同源物。然后，我们从系统发育的角度分析了基因结构。并对它们的表达模式进行了分析，得到以下结果：a.克隆了编码黑色素生物合成关键酶的海鞘酪氨酸酶基因，并分析了其表达模式。还克隆了推测的海鞘酪氨酸酶相关蛋白基因。该基因在海鞘发育过程中表现出非常早的表达，与脊椎动物同源基因相似。我们在其调节区域中鉴定了几个顺式作用元件。d.海鞘MITF（microphthalmia-associated transcription factor）基因已被克隆，已知脊椎动物MITF可激活酪氨酸酶及其相关基因的表达。我们发现MITF-M是脊椎动物神经嵴细胞向黑素细胞分化所必需的一种亚型。海鞘MITF同源物不能表达M-异构体。海鞘MITF同源物可以反式激活海鞘酪氨酸酶和酪氨酸酶相关蛋白基因，也可以激活脊椎动物酪氨酸酶和TRP基因。另一方面，只有一种脊椎动物的MITF异构体可以反式激活海鞘TRP基因。

项目成果

Shigeru Sato: "Ascidian Tyrosinase Gene : Its Unique Structure and Expression in the Developing Brain" Developmental Dynamics. 208. 1-12 (1997)

Shigeru Sato：“海鞘酪氨酸酶基因：其独特的结构和在发育中大脑中的表达”发育动力学。

Amae, S: "Identification of a novel isoform of microphthalmia-associated transcription factor that is enriched in pigment epithelium." Biochem.Biophys.Res.Comm.247. 710-715 (1998)

Amae，S：“鉴定出一种新的小眼症相关转录因子亚型，该因子富含色素上皮。”

Amae,S: "Identification of a novel isoform of microphthalmia-associated transcription facto that is enriched in pigment epithelium." Biochem.Biophys.Res.Comm.247. 710-715 (1998)

Amae，S：“鉴定出一种新的小眼症相关转录因子亚型，该因子富含色素上皮。”

Yuasa,H.J.genes:the: "The structural organization of the ascidian,Halocynthia roretzi calmodulin vicissitude of introns during the evolution of calmodulin genes." Gene,accepted.(1999)

Yuasa，H.J.genes：“海鞘的结构组织，Halocynthia roretzi 钙调蛋白内含子在钙调蛋白基因进化过程中的变迁。”

Sato, S.: "Ascidian tyrosinase gene:its unique structure and expression in the developing brain" Developmental Dynamics. 208. 363-374 (1997)

Sato, S.：“海鞘酪氨酸酶基因：其独特的结构和在发育中大脑中的表达”发育动力学。