Parlati F, Weber T, McNew J A, Westermann B, Söllner T H, Rothman J E
Cellular Biochemistry Program, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, Box 251 New York, NY 10021, USA.
Proc Natl Acad Sci U S A. 1999 Oct 26;96(22):12565-70. doi: 10.1073/pnas.96.22.12565.
A protease-resistant core domain of the neuronal SNARE complex consists of an alpha-helical bundle similar to the proposed fusogenic core of viral fusion proteins [Skehel, J. J. & Wiley, D. C. (1998) Cell 95, 871-874]. We find that the isolated core of a SNARE complex efficiently fuses artificial bilayers and does so faster than full length SNAREs. Unexpectedly, a dramatic increase in speed results from removal of the N-terminal domain of the t-SNARE syntaxin, which does not affect the rate of assembly of v-t SNARES. In the absence of this negative regulatory domain, the half-time for fusion of an entire population of lipid vesicles by isolated SNARE cores ( approximately 10 min) is compatible with the kinetics of fusion in many cell types.
神经元SNARE复合体的蛋白酶抗性核心结构域由一个α-螺旋束组成，类似于病毒融合蛋白的假定融合核心[斯凯尔，J. J. & 威利，D. C.（1998年）《细胞》95卷，871 - 874页]。我们发现，分离出的SNARE复合体核心能高效融合人工双层膜，且比全长SNARE融合得更快。出乎意料的是，去除t-SNARE syntaxin的N端结构域会导致速度大幅提升，而这并不影响v-t SNARE的组装速率。在没有这个负调控结构域的情况下，分离出的SNARE核心使整群脂质囊泡融合的半衰期（约10分钟）与许多细胞类型中的融合动力学相匹配。
