Comparison of the mechanism on functional expression of diverged rhodopsins by using their mutants

利用突变体比较不同视紫红质的功能表达机制

• 批准号: 13640678
• 负责人: TERAKITA Akihisa
• 金额: $ 2.24万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13640678/
• 关键词: rhodopsin; opsin family; diversity; retinal schiff-base; counterion; G protein; photoisomerase; レチナール・シッフ塩基

The members of rhodopsin family are divided into at least five subgroups. In this study, the amphioxus Go-coupled rhodopsin and peropsin were investigated to understand the mechanism on the functional expression of diverged rhodopsins ; specifically, 1. comparison of the amino acid residue which functions as counterion 2.comparison of G protein activation mechanism between Go-coupled rhodopsin and vertebrate rhodopsins, and then 3. investigation of physiological function of peropsin.Results :1. Unlike bovine rhodopsin but like retinochrome, amphioxus relatives belonging to the groups of Go-coupled rhodopsins and peropsins have the glutamic acid counterions at position 181 in the 2nd extracellular loop.2. We established the procedures to measure the G protein activation ability of the amphioxus rhodopsin to strictly compare the G protein activation mechanism with vertebrate rhodopsins.3. HPLC analyses of chromophore retinal revealed that peropsin has all-trans-retinal as the chromophore, and light causes the isomerization from all-trans to 11-cis. This finding suggested that peropsin functions as photoisomerase like retinochrome and RGR.

视紫红质家族的成员被分为至少五个亚群。本研究通过对文昌鱼go偶联的视紫红质和peropsin进行研究，了解分化的视紫红质功能表达的机制；具体地说,1。2. go偶联视紫红质与脊椎动物视紫红质之间G蛋白活化机制的比较；肌肽生理功能的研究。结果:1。与牛视紫红质不同的是，文文鱼的近亲属于go偶联的视紫红质和视紫红质，在第2细胞外环的第181位有谷氨酸反离子。我们建立了测定文文鱼视紫红质G蛋白活化能力的方法，以严格比较文文鱼视紫红质与脊椎动物视紫红质的G蛋白活化机制。对视网膜发色团的HPLC分析表明，peropsin以全反式视网膜为发色团，光使其从全反式异构化为11-顺式。这一发现提示peropsin与视黄色素和RGR一样具有光异构酶的功能。

项目成果

T.Nagata: "Isomer-specific interaction of the retinal chromophore with threonine-118 in rhodopsin"J.Phys.Chem.. 106. 1969-1975 (2002)

T.Nagata：“视紫红质中视网膜发色团与苏氨酸 118 的异构体特异性相互作用”J.Phys.Chem.. 106. 1969-1975 (2002)

M.Koyanagi: "Amphioxus homologs of Go-coupled rhodopsin and peropsin having 11-cis-and all-trans-retinals as their chromophores"FEBS Lett.. 531. 525-528 (2002)

M.Koyanagi：“Go 偶联视紫红质和视蛋白的文昌鱼同系物具有 11-顺式-和全反式-视网膜作为其发色团”FEBS Lett.. 531. 525-528 (2002)

M.Koyanagi: "Amphioxus homologs of Go-coupled rhodopsin and peropsin havin 11-cis-and all-trans-retinals as thier chromophores"FEBS Lett.. 531. 525-528 (2002)

M.Koyanagi：“Go 偶联视紫红质和视紫红质的文昌鱼同系物具有 11-顺式-和全反式-视网膜作为其发色团”FEBS Lett.. 531. 525-528 (2002)

岡田哲二: "ロドプシンの結晶構造からみるG蛋白質共役受容体の構造・機能関連"蛋白質核酸酵素. 147. 1123-1130 (2002)

Tetsuji Okada：“从视紫红质晶体结构看到的 G 蛋白偶联受体的结构和功能关系”蛋白质核酸酶 147. 1123-1130 (2002)

Y.Nakashima: "Origin of the vertebrate visual cycle : retinal photoisomerase and two putative visual cycle proteins are expressed in whole brain of a primitive"J. Comp. Neurol.. 印刷中. (2003)

Y. Nakashima：“脊椎动物视觉周期的起源：视网膜光异构酶和两种假定的视觉周期蛋白在原始人的整个大脑中表达”J. Comp。