Transmission of coupling energy from catalytic site to Ca^<2+> transport sites in endoplasmic reticulum calcium pump

内质网钙泵中催化位点到Ca^2>转运位点的耦合能量传输

• 批准号: 16570091
• 负责人: DAIHO Takashi
• 金额: $ 2.43万
• 依托单位: Asahikawa Medical College
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16570091/
• 关键词: sarcoplasmic reticulum; Ca^<2+>-ATPase; phosphoenzyme; active transport; SERCA; calcium pump; P-type ATPase; Darier Disease; Sarcoplasmic Reticulum; Ca2+-ATPase; Hydrophobic Interaction; Ca2+ transport; Calcium pump; phosphoenzym

Sarco(endo)plasmic reticulum Ca^<2+>-ATPase (SERCA) transport Ca^<2+> ions from cytoplasm into lumen coupled with ATP hydrolysis, and has essential roles in Ca^<2+> homeostasis. The Ca^<2+> transport sites are located in transmembrane domain, while catalytic site is in the three cytoplasmic domains (A,P, and N). P-domain is phosphorylated with ATP bound to N-domain. Biochemical studies on the intermediates and their analogs indicated that the large rotation of A-domain and its tight association with P-domain occur during the conformational transition of the phosphorylated intermediate (E1P to E2P) and Ca^<2+> release. 1.The author found that Tyr^<122> on the loop connecting A-domain and the 2^<nd> transmembrane helix and other hydrophobic six residues are critical for the hydrophobic interactions between A- and P-domains in the transition and hydrolysis of E2P. 2.The structural natures of stable analogs for E2P of Ca^<2+>-ATPase, i.e. E2BeF,E2A1F, and E2MgF, were explored and compared with actual E2P. It was suggested that the change in hydrophobic nature around phosphorylation site is associated with the change in phosphate geometry from BeF_<3^-> to AlF_3 or AlF_<4^-> and further to MgF_<4^<2->>. Such change likely rearranges transmembrane helices to prevent leakage of lumenal Ca^<2+>. 3.Possible functional abnormalities in three different Darier disease-causing SERCA2b mutants, I274V,L321F, and M719I. Essentially normal expression levels and only slightly reduced Ca^<2+> transport activities of I274V and M719I as compared with wild type suggest that physiological requirement for Ca^<2+> homeostasis in keratinocytes to avoid haploinsufficiency is very strict. The insensitivity to lumenal Ca^<2+> in L321F could possibly be associated with the neuropsychiatric disorder in the pedigee.

肌浆网Ca^2+-ATP酶（SERCA）是肌浆网Ca^2+的转运酶，参与ATP的水解，在维持Ca^2+稳态中发挥重要作用。Ca^2+转运位点位于跨膜区，而催化位点位于胞质的三个区域（A、P和N）。P结构域被结合到N结构域的ATP磷酸化。对中间体及其类似物的生化研究表明，在磷酸化中间体的构象转变（E1 P到E2 P）和Ca^2+释放过程中，A结构域发生了大的旋转并与P结构域紧密结合。1.作者发现，<122>连接A结构域和2^跨膜螺旋的环上<nd>的Tyr^和其他疏水性六个残基对于E2 P的过渡和水解中A结构域和P结构域之间的疏水相互作用是关键的。2.对Ca^&lt;2+&gt;-ATP酶E2 P的稳定类似物E2 BeF、E2 A1 F和E2 MgF的结构性质进行了探索，并与实际E2 P进行了比较。结果表明，磷酸化位点周围疏水性的变化与磷酸盐几何构型从BeF_（3^-）到AlF_（3 ^-）或AlF_（4^-）再到MgF_（4^-）的变化有关<2->。这种变化可能是为了重新排列跨膜螺旋以防止腔内Ca^2+的泄漏。3.三种不同的Darier病致病SERCA 2b突变体I274 V、L321 F和M719 I可能存在功能异常与野生型相比，I274 V和M719 I的表达水平基本正常，Ca^2+转运活性仅略有降低，这表明角质形成细胞中Ca^2+稳态以避免单倍性不足的生理要求非常严格。L321 F对腔内Ca^&lt;2+&gt;的不敏感性可能与该家系的神经精神障碍有关。

项目成果

Analysis of Ca^<2+>-release process in the phosphorylated intermediates of sarcoplasmic reticulum Ca^<2+>-ATPase by mutagenesis

肌浆网Ca^2-ATP酶磷酸化中间体Ca^2-释放过程的诱变分析

• 发表时间: 2005
• 期刊: 生化学 77・8
• 作者: Yoshida;M. et al.;Masaki Yoshida;Guoli Wang;Takashi Daiho;Kazuo Yamasaki
• 通讯作者: Kazuo Yamasaki

Distinct type of Abnormality is Kinetic Properties of Three Darier Disease-causing Sarco(endo)plasmic Reticulum Ca2+-ATPase (SERCA2b) Mutants

不同类型的异常是三种引起 Darier 病的肌（内）质网 Ca2 -ATP 酶 (SERCA2b) 突变体的动力学特性

• 发表时间: 2004
• 期刊: 生化学 76・8
• 作者: Hiroshi Suzuki;et al.;Kazuo Yamasaki
• 通讯作者: Kazuo Yamasaki

Distinct natures of Be/F-bound, Al/F-bound, and Mg/F-bound stable analogues of an ADP-insensitive phosphoenzyme intermediate of sarcoplasmic reticulum Ca^<2+>-ATPase

肌浆网Ca^2-ATP酶的ADP不敏感磷酸酶中间体的Be/F结合、Al/F结合和Mg/F结合稳定类似物的独特性质

• 发表时间: 2004
• 期刊: 生化学 76・8
• 作者: Wang;G. et al.;Takashi Daiho;鈴木 裕;Kazuo Yamasaki;Takashi Daiho;Guoli Wang;Hiroshi Suzuki
• 通讯作者: Hiroshi Suzuki

ATP2C1 is specifically localized in the basal layer of normal epidermis and its depletion triggers keratinocyte differentiation.

• DOI: 10.1016/j.jdermsci.2006.03.003
• 发表时间: 2006-07
• 期刊: Journal of dermatological science
• 影响因子: 4.6
• 作者: Masaki Yoshida;K. Yamasaki;T. Daiho;H. Iizuka;Hiroshi Suzuki

Distinct natures of beryllium fluoride-bound, aluminum fluoride-bound, and magnesium fluoride-bound stable analogues of an ADP-insensitive phosphoenzyme intermediate of sarcoplasmic reticulum Ca2+-ATPase : changes in catalytic and transport sites during p

肌浆网 Ca2-ATP 酶的 ADP 不敏感磷酸酶中间体的氟化铍结合、氟化铝结合和氟化镁结合稳定类似物的不同性质：p 过程中催化和运输位点的变化

• 发表时间: 2004
• 期刊: The Journal of Biological Chemistry 279・15
• 作者: Kazuo Yamasaki;et al.;Kazuo Yamasaki;Takashi Daiho;Guoli Wang;Hiroshi Suzuki;Stefania Danko
• 通讯作者: Stefania Danko