Núcleo de Biotecnologia, Universidade Federal do Espírito Santo, Vitória, Brazil.
Biochimie. 2012 Feb;94(2):525-32. doi: 10.1016/j.biochi.2011.09.001. Epub 2011 Sep 10.
The crystal structure and pro-inflammatory property of a lectin from the seeds of Dioclea wilsonii (DwL) were analyzed to gain a better understanding of structure/function relationships of Diocleinae lectins. Following crystallization and structural determination by standard molecular replacement techniques, DwL was found to be a tetramer based on PISA analysis, and composed by two metal-binding sites per monomer and loops which are involved in molecular oligomerization. DwL presents 96% and 99% identity with two other previously described lectins of Dioclea rostrata (DRL) and Dioclea grandiflora (DGL). DwL differs structurally from DVL and DRL with regard to the conformation of the carbohydrate recognition domain and related biological activities. The structural analysis of DwL in comparison to other Diocleinae lectins can be related to the differences in the dose-dependent pro-inflammatory effect elicited in Wistar rats, probably via specific interactions with mast cells complex carbohydrate, resulting in significant paw edema. DwL appears to be involved in positive modulation of mast cell degranulation via recognition of surface carbohydrates. Since this recognition is dependent on site volume and CRD configuration, edematogenesis mediated by resident cells varies in potency and efficacy among different Diocleinae lectins.
分析了来自 Dioclea wilsonii（DwL）种子的凝集素的晶体结构和促炎特性，以更好地了解 Diocleinae 凝集素的结构/功能关系。通过标准的分子置换技术进行结晶和结构测定后，发现 DwL 基于 PISA 分析是一个四聚体，由每个单体的两个金属结合位点和参与分子寡聚化的环组成。 DwL 与之前描述的 Dioclea rostrata（DRL）和 Dioclea grandiflora（DGL）的两种其他凝集素有 96%和 99%的同一性。在结构上，与 DVL 和 DRL 相比， DwL 的碳水化合物识别域的构象和相关的生物学活性存在差异。与其他 Diocleinae 凝集素的结构分析相比，这种差异可能与在 Wistar 大鼠中引起的剂量依赖性促炎作用有关，这可能是通过与肥大细胞复杂碳水化合物的特异性相互作用引起的，导致明显的爪肿胀。 DwL 似乎通过识别表面碳水化合物参与肥大细胞脱颗粒的正调节。由于这种识别取决于部位体积和 CRD 构象，因此不同 Diocleinae 凝集素介导的驻留细胞水肿的效力和功效存在差异。
