Kluyveromyces lactis gamma-toxin, a ribonuclease that recognizes the anticodon stem loop of tRNA.
Kluyveromyces lactis gamma-toxin, a ribonuclease that recognizes the anticodon stem loop of tRNA.
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DOI：
10.1093/nar/gkm1121
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发表时间：
2008-03
影响因子：
14.9
通讯作者：
Byström AS
中科院分区：
文献类型：
--
作者：
Lu J;Esberg A;Huang B;Byström AS
乳酸克鲁维酵母γ-毒素是一种切割酿酒酵母的tRNA内切核酸酶，位于位置34和位置35之间。所有三种底物tRNA在第34位（摆动位置）携带5-甲氧羰基甲基-2-硫尿苷（mcm 5s 2U）残基，其中mcm 5基团是有效切割所需的。然而，不同的切割效率的mcm 5s 2U 34-含有的tRNA表明，这些tRNA的其他功能影响切割。在本研究中，我们发现，一个稳定的反密码子茎和反密码子环的最低要求切割的γ-毒素。对应于天然底物的反密码子茎环（ASL）的合成微螺旋RNA在与天然底物相同的位置被切割。在中，核苷酸U34 U35 C36 A37 C38是最佳γ-毒素切割所需的，而位置32处的嘌呤或位置33处的G显著降低ASL的切割。比较E.大肠杆菌和酵母加强了MCM 5组的强刺激作用，显示了S2组的弱正作用和细菌5-甲基氨基甲基（MnM 5）组的负作用。这些数据强调了这种酵母tRNA毒素的高度特异性。
Kluyveromyces lactis γ-toxin is a tRNA endonuclease that cleaves Saccharomyces cerevisiae , and between position 34 and position 35. All three substrate tRNAs carry a 5-methoxycarbonylmethyl-2-thiouridine (mcm5s2U) residue at position 34 (wobble position) of which the mcm5 group is required for efficient cleavage. However, the different cleavage efficiencies of mcm5s2U34-containing tRNAs suggest that additional features of these tRNAs affect cleavage. In the present study, we show that a stable anticodon stem and the anticodon loop are the minimal requirements for cleavage by γ-toxin. A synthetic minihelix RNA corresponding to the anticodon stem loop (ASL) of the natural substrate is cleaved at the same position as the natural substrate. In , the nucleotides U34U35C36A37C38 are required for optimal γ-toxin cleavage, whereas a purine at position 32 or a G in position 33 dramatically reduces the cleavage of the ASL. Comparing modified and partially modified forms of E. coli and yeast reinforced the strong stimulatory effects of the mcm5 group, revealed a weak positive effect of the s2 group and a negative effect of the bacterial 5-methylaminomethyl (mnm5) group. The data underscore the high specificity of this yeast tRNA toxin.
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影响因子：
2.9
作者：
Lin, YL;Elias, Y;Huang, RH
通讯作者：
Huang, RH
影响因子：
5.6
作者：
Hagervall, TG;Pomerantz, SC;McCloskey, JA
通讯作者：
McCloskey, JA
影响因子：
64.8
作者：
SUGISAKI, Y;GUNGE, N;TAMURA, G
通讯作者：
TAMURA, G
DOI：
10.1073/pnas.85.4.1033
发表时间：
1988-02-01
影响因子：
11.1
作者：
SAMPSON, JR;UHLENBECK, OC
通讯作者：
UHLENBECK, OC
影响因子：
11.4
作者：
AMITSUR, M;LEVITZ, R;KAUFMANN, G
通讯作者：
KAUFMANN, G