Instituto de Biologia Molecular y Celular, Universidad Miguel Hernandez, Elche, Alicante, Spain.
Biomacromolecules. 2010 Aug 9;11(8):2069-78. doi: 10.1021/bm100432x.
Assembly of the mature human immunodeficiency virus type 1 capsid involves the oligomerization of the capsid protein, CA. The C-terminal domain of CA, CTD, participates both in the formation of CA hexamers and in the joining of hexamers through homodimerization. Intact CA and the isolated CTD are able to homodimerize in solution with similar affinity (dissociation constant in the order of 10 microM); CTD homodimerization involves mainly an alpha-helical region. In this work, we show that first-generation gallic acid-triethylene glycol (GATG) dendrimers bind to CTD. The binding region is mainly formed by residues involved in the homodimerization interface of CTD. The dissociation constant of the dendrimer-CTD complexes is in the range of micromolar, as shown by ITC. Further, the affinity for CTD of some of the dendrimers is similar to that of synthetic peptides capable of binding to the dimerization region, and it is also similar to the homodimerization affinity of both CTD and CA. Moreover, one of the dendrimers, with a relatively large hydrophobic moiety at the dendritic branching (a benzoate), was able to hamper the assembly in vitro of the human immunodeficiency virus capsid. These results open the possibility of considering dendrimers as lead compounds for the development of antihuman immunodeficiency virus drugs targeting capsid assembly.
组装成熟的人类免疫缺陷病毒 1 型衣壳涉及衣壳蛋白 CA 的寡聚化。CA 的 C 末端结构域（CTD）既参与六聚体的形成，又通过同源二聚化参与六聚体的连接。完整的 CA 和分离的 CTD 都能够在溶液中以相似的亲和力（解离常数在 10 微摩尔左右）同源二聚化；CTD 同源二聚化主要涉及一个α-螺旋区域。在这项工作中，我们表明第一代没食子酸-三乙二醇（GATG）树枝状大分子与 CTD 结合。结合区域主要由涉及 CTD 同源二聚化界面的残基形成。通过 ITC 显示，树枝状大分子-CTD 复合物的解离常数在微摩尔范围内。此外，一些树枝状大分子与能够结合二聚化区域的合成肽对 CTD 的亲和力相似，与 CTD 和 CA 的同源二聚化亲和力也相似。此外，树枝状大分子中的一种（带有相对较大的疏水性部分的苯甲酸酯）在体外能够阻碍人类免疫缺陷病毒衣壳的组装。这些结果为考虑树枝状大分子作为针对衣壳组装的抗人类免疫缺陷病毒药物的先导化合物开辟了可能性。
