Research Resource: Correlating Human Cytochrome P450 21A2 Crystal Structure and Phenotypes of Mutations in Congenital Adrenal Hyperplasia.
Research Resource: Correlating Human Cytochrome P450 21A2 Crystal Structure and Phenotypes of Mutations in Congenital Adrenal Hyperplasia.
复制标题
DOI：
10.1210/me.2015-1127
复制
发表时间：
2015-07
影响因子：
--
通讯作者：
P. Pallan;L. Lei;Chunxue Wang;Michael R. Waterman;F. Guengerich;M. Egli
中科院分区：
文献类型：
--
作者：
P. Pallan;L. Lei;Chunxue Wang;Michael R. Waterman;F. Guengerich;M. Egli
细胞色素P45021A2是类固醇21-羟基化的关键分子，它将孕酮转化为11-脱氧皮质酮，将17-α-羟基孕酮转化为11-脱氧皮质醇。到目前为止，已在患者中确定了100多个P450 21A2突变；这些突变占了先天性肾上腺增生症(CAH)的绝大多数，CAH是人类最常见的可遗传代谢性疾病之一。CAH的表型范围从最严重的盐耗(SW)，到简单的阳春化(SV)和非经典(NC)CAH。我们最近测定了人P45021A2与黄体酮的络合物的晶体结构。为了更深入地了解单个突变表型的结构和稳定性变化，我们在人酶晶体结构的背景下分析了24个SW、SV和NC突变。我们的分析显示，SW、SV和NC突变的定位有明显的差异，许多第一种类型的突变映射到活性部位以及靠近血红素和/或底物，主要导致酶活性的完全丧失。相反，NC突变通常在蛋白质的外围和表面附近发现，突变酶保持部分活性。突变-结构-活性研究的主要结论是，CAH临床表现的严重程度可以直接与突变引起的结构模型中蛋白质折叠稳定性和活性部位变化的损害程度相关。因此，NC表型通常与具有补偿作用的突变相关，即氢键取代疏水相互作用，反之亦然。
Cytochrome P450 21A2 is a key player in steroid 21-hydroxylation and converts progesterone to 11-deoxycorticosterone and 17α-hydroxy progesterone to 11-deoxycortisol. More than 100 mutations in P450 21A2 have been established in patients thus far; these account for the vast majority of occurrences of congenital adrenal hyperplasia (CAH), which is among the most common heritable metabolic diseases in humans. CAH phenotypes range from the most severe, salt-wasting (SW), to the simple virilizing (SV), and nonclassical (NC) CAH forms. We recently determined the crystal structure of human P450 21A2 in complex with progesterone. To gain more insight into the structural and stability changes underlying the phenotypes of individual mutations, we analyzed 24 SW, SV, and NC mutants in the context of the crystal structure of the human enzyme. Our analysis reveals clear differences in the localization of SW, SV, and NC mutations, with many of the first type mapping to the active site and near the heme and/or substrate and mostly resulting in complete loss of enzyme activity. Conversely, NC mutations are often found near the periphery and close to the surface of the protein, and mutant enzymes retain partial activity. The main conclusion from the mutation-structure-activity study is that the severity of the CAH clinical manifestations can be directly correlated with the degree of mutation-induced damage in terms of protein fold stability and active site changes in the structural model. Thus, the NC phenotype is typically associated with mutations that have a compensatory effect, ie, H-bonding replacing hydrophobic interactions and vice versa.