Human DHEA sulfation requires direct interaction between PAPS synthase 2 and DHEA sulfotransferase SULT2A1.
Human DHEA sulfation requires direct interaction between PAPS synthase 2 and DHEA sulfotransferase SULT2A1.
复制标题
DOI：
10.1074/jbc.ra118.002248
复制
发表时间：
2018-06-22
期刊：
影响因子：
--
通讯作者：
Arlt W
中科院分区：
文献类型：
--
作者：
Mueller JW;Idkowiak J;Gesteira TF;Vallet C;Hardman R;van den Boom J;Dhir V;Knauer SK;Rosta E;Arlt W
高能硫酸盐供体3‘-磷酸腺苷-5’-磷酸硫酸盐(PAPS)由人PAPS合成酶亚型PAPSS1和PAPSS2产生，是所有人类硫化途径所必需的。磺基转移酶SULT2A1使用PAPS对雄激素前体脱氢表雄酮(DHEA)进行硫酸盐化，从而减少DHEA下游对活性雄激素的激活。人类PAPSS2突变表现为不可检测的DHEA硫酸盐、雄激素过剩和代谢性疾病，表明无处不在的PAPSS1不能弥补PAPSS2在支持DHEA硫化方面的不足。在对人肾上腺皮质NCI-H295R1细胞的基因敲除研究中，我们发现有效的DHEA硫化需要PAPSS2，而不是PAPSS1。在PAPSS1和PAPSS2中，PAPSS1和PAPSS2中特定的APS激酶活性是PAPS生物合成中的限速步骤。胞质SULT2A1与胞质PAPSS2变异体共表达比与核/胞质PAPSS1共表达更有效地支持DHEA硫化。邻近连接分析表明，SULT2A1和PAPSS2之间存在蛋白质-蛋白质相互作用，程度较小的是PAPSS1。分子对接研究表明，SULT2A1在PAPSS2 APS激活域中有一个可能的结合位点。对接溶液的能量依赖评分确定了PAPSS2和SULT2A1亚型的相互作用是特异的。这些发现阐明了在人DHEA硫化反应中对PAPSS2的选择性要求的机制基础。
The high-energy sulfate donor 3′-phosphoadenosine-5′-phosphosulfate (PAPS), generated by human PAPS synthase isoforms PAPSS1 and PAPSS2, is required for all human sulfation pathways. Sulfotransferase SULT2A1 uses PAPS for sulfation of the androgen precursor dehydroepiandrosterone (DHEA), thereby reducing downstream activation of DHEA to active androgens. Human PAPSS2 mutations manifest with undetectable DHEA sulfate, androgen excess, and metabolic disease, suggesting that ubiquitous PAPSS1 cannot compensate for deficient PAPSS2 in supporting DHEA sulfation. In knockdown studies in human adrenocortical NCI-H295R1 cells, we found that PAPSS2, but not PAPSS1, is required for efficient DHEA sulfation. Specific APS kinase activity, the rate-limiting step in PAPS biosynthesis, did not differ between PAPSS1 and PAPSS2. Co-expression of cytoplasmic SULT2A1 with a cytoplasmic PAPSS2 variant supported DHEA sulfation more efficiently than co-expression with nuclear PAPSS2 or nuclear/cytosolic PAPSS1. Proximity ligation assays revealed protein–protein interactions between SULT2A1 and PAPSS2 and, to a lesser extent, PAPSS1. Molecular docking studies showed a putative binding site for SULT2A1 within the PAPSS2 APS kinase domain. Energy-dependent scoring of docking solutions identified the interaction as specific for the PAPSS2 and SULT2A1 isoforms. These findings elucidate the mechanistic basis for the selective requirement for PAPSS2 in human DHEA sulfation.