Astacin proteases cleave dentin sialophosphoprotein (Dspp) to generate dentin phosphoprotein (Dpp).
Astacin proteases cleave dentin sialophosphoprotein (Dspp) to generate dentin phosphoprotein (Dpp).
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DOI：
10.1002/jbmr.202
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发表时间：
2011-01
影响因子：
6.2
通讯作者：
Yamakoshi, Yasuo
中科院分区：
文献类型：
--
作者：
Tsuchiya, Shuhei;Simmer, James P.;Hu, Jan C-C;Richardson, Amelia S.;Yamakoshi, Fumiko;Yamakoshi, Yasuo
牙本质唾液磷蛋白（Dspp）对牙本质生物矿化至关重要，因为Dspp的遗传缺陷会导致II型牙本质发育不良和II型和III型牙本质发育不全。Dspp被蛋白酶加工成更小的亚基；初始裂解释放牙本质磷蛋白（Dpp）。我们用BMP-1、MEP1A、MEP1B、MMP-2、MMP-8、MMP-9、MT1-MMP、MT3-MMP、Klk4、MMP-20、纤浆蛋白或猪Dpp孵育含有Dpp切割位点氨基酸背景的荧光共振能量转移（FRET）肽（YEFDGKSMQGDDPN，指定Dspp-FRET）或该背景的突变版本（YEFDGKSIEGDDPN，指定mutDspp-FRET），并对肽切割产物进行了表征。在体内，只有BMP-1、MEP1A和MEP1B在G-D肽键上切割Dspp- fret，从而从Dspp中释放Dpp。我们从牙本质粉末中分离出Dspp蛋白多糖，并将其与三种在G-D键处裂解Dspp- fret的酶一起培养。在每种情况下，释放的Dpp结构域被分离出来，其n端以Edman降解为特征。BMP-1和MEP1A都在正确的位点切割天然Dspp以生成Dpp，这使得这两种酶都成为在体内切割Dspp的蛋白酶的主要候选者。当Dpp浓度足够高，使游离钙离子浓度耗尽时，MEP1B能够降解Dpp。发育中的猪磨牙的免疫组织化学表明，astacins是由成牙细胞表达的，这一结果与RT-PCR分析一致。我们得出结论，在成牙过程中，预牙基质中的astacins在Dpp的n端序列之前切割Dspp，从而将Dpp从亲本Dspp蛋白中释放出来。©2011美国骨与矿物研究学会。
Dentin sialophosphoprotein (Dspp) is critical for proper dentin biomineralization because genetic defects in DSPP cause dentin dysplasia type II and dentinogenesis imperfecta types II and III. Dspp is processed by proteases into smaller subunits; the initial cleavage releases dentin phosphoprotein (Dpp). We incubated fluorescence resonance energy transfer (FRET) peptides containing the amino acid context of the Dpp cleavage site (YEFDGKSMQGDDPN, designated Dspp-FRET) or a mutant version of that context (YEFDGKSIEGDDPN, designated mutDspp-FRET) with BMP-1, MEP1A, MEP1B, MMP-2, MMP-8, MMP-9, MT1-MMP, MT3-MMP, Klk4, MMP-20, plasmin, or porcine Dpp and characterized the peptide cleavage products. Only BMP-1, MEP1A, and MEP1B cleaved Dspp-FRET at the G–D peptide bond that releases Dpp from Dspp in vivo. We isolated Dspp proteoglycan from dentin power and incubated it with the three enzymes that cleaved Dspp-FRET at the G–D bond. In each case, the released Dpp domain was isolated, and its N-terminus was characterized by Edman degradation. BMP-1 and MEP1A both cleaved native Dspp at the correct site to generate Dpp, making both these enzymes prime candidates for the protease that cleaves Dspp in vivo. MEP1B was able to degrade Dpp when the Dpp was at sufficiently high concentration to deplete free calcium ion concentration. Immunohistochemistry of developing porcine molars demonstrated that astacins are expressed by odontoblasts, a result that is consistent with RT-PCR analyses. We conclude that during odontogenesis, astacins in the predentin matrix cleave Dspp before the DDPN sequence at the N-terminus of Dpp to release Dpp from the parent Dspp protein. © 2011 American Society for Bone and Mineral Research.
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影响因子：
--
作者：
LINDE, A
通讯作者：
LINDE, A
影响因子：
56.9
作者：
Kessler, E;Takahara, K;Greenspan, DS
通讯作者：
Greenspan, DS
影响因子：
5.3
作者：
Pappano, WN;Steiglitz, BM;Greenspan, DS
通讯作者：
Greenspan, DS
影响因子：
4.8
作者：
Qin, CL;Cook, RG;Butler, WT
通讯作者：
Butler, WT
DOI：
10.1016/s0934-8832(11)80030-2
发表时间：
1992-11-01
期刊：
MATRIX
影响因子：
--
作者：
BUTLER, WT;BHOWN, M;VANDIJK, S
通讯作者：
VANDIJK, S