PPPYEPTAP motif is the late domain of human T-Cell leukemia virus type 1 GaG and mediates its functional interaction with cellular proteins Nedd4 and Tsg101
PPPYEPTAP motif is the late domain of human T-Cell leukemia virus type 1 GaG and mediates its functional interaction with cellular proteins Nedd4 and Tsg101
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DOI：
10.1128/jvi.77.22.11882-11895.2003
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发表时间：
2003-11-01
影响因子：
5.4
通讯作者：
Goff, SP
中科院分区：
文献类型：
--
作者：
Bouamr, F;Melillo, JA;Goff, SP
人T细胞白血病病毒1型（HTLV-1）Gag多蛋白在基质结构域的C末端含有两个相邻的富含脯氨酸的基序（序列PPPYEPTAP）。将脯氨酸至丙氨酸突变引入HTLV-1的任一或两个基序中以确定对HTLV-1病毒样颗粒从293 T细胞释放的影响。两个单突变体的释放显着减少，而在两个基序的双重突变废除了HTLV-1颗粒的释放。双杂交和体外结合试验表明，HTLV-1 Gag多蛋白结合Tsg 101和Nedd 4蛋白。与HTLV-1 Gag的相互作用需要Nedd 4的中心WW结构域和Tsg 101的泛素酶变体（UEV）结构域。我们在293 T细胞中表达了Nedd 4和Tsg 101蛋白的各种片段，并测试了它们干扰HTLV-1 Gag-Pro多聚蛋白介导的病毒体释放的能力。由Tsg 101的N-末端UEV结构域和Nedd 4蛋白的中央WW和C-末端Hect结构域组成的片段均引起HTLV-1颗粒释放的反式显性抑制。类似地，蛋白酶体的抑制显著降低了HTLV-1颗粒的释放。此外，WW结构域过表达导致在膜变形为典型的半壳结构之前HTLV-1颗粒形态发生的早期停滞。这一结果表明Nedd 4参与了HTLV-1的早期出芽。
The human T-cell leukemia virus type 1 (HTLV-1) Gag polyprotein contains two adjacent proline-rich motifs (sequence PPPYEPTAP) in the C terminus of the matrix domain. Proline-to-alanine mutations were introduced into either or both motifs of HTLV-1 to determine the effect on the release of HTLV-1 virus-like particles from 293T cells. The release of both single mutants was significantly reduced, whereas a double mutation in both motifs abolished the release of the HTLV-1 particles. Two-hybrid and in vitro binding assays showed that the HTLV-1 Gag polyprotein binds both Tsg101 and Nedd4 proteins. The interaction with HTLV-1 Gag required the central WW domain of Nedd4 and the ubiquitin enzyme variant (UEV) domain of Tsg101. We expressed various fragments of Nedd4 and Tsg101 proteins in 293T cells and tested for their ability to interfere with virion release mediated by the HTLV-1 Gag-Pro polyprotein. Fragments consisting of the N-terminal UEV domain of Tsg101 and the central WW and C-terminal Hect domains of Nedd4 protein all caused transdominant inhibition of HTLV-1 particle release. Similarly, inhibition of the proteasome significantly decreased HTLV-1 particle release. Furthermore, the WW domain overexpression caused an early arrest of HTLV-1 particle morphogenesis before the membrane is deformed into the typical half-shell structure. This result suggests that Nedd4 is involved early in budding of HTLV-1.