δ/ω-Plectoxin-Pt1a: an excitatory spider toxin with actions on both Ca(2+) and Na(+) channels.
δ/ω-Plectoxin-Pt1a: an excitatory spider toxin with actions on both Ca(2+) and Na(+) channels.
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DOI：
10.1371/journal.pone.0064324
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发表时间：
2013
期刊：
影响因子：
3.7
通讯作者：
Branton WD
中科院分区：
文献类型：
--
作者：
Zhou Y;Zhao M;Fields GB;Wu CF;Branton WD
蜘蛛的毒液含有多种肽毒素，选择性地靶向神经元离子通道。苏氨酸或丝氨酸残基的O-棕榈酰化，沿着特征性的高度受限的二硫键结构，是在这种毒液中发现的毒素家族的标志。在这里，我们报告了一个新的毒素，δ/ω-plectoxin-Pt 1a，从这种蜘蛛毒液的分离和表征。它是含有O-棕榈酰化Ser-39的40个氨基酸肽。对δ/ω-plectoxin-Pt 1a cDNA的分析揭示了一个含有分泌信号序列、一个14个氨基酸的N-末端前肽和一个C-末端酰胺化信号的小前体。δ/ω-plectoxin-Pt 1a的生物活性也是独特的。它优先阻断神经递质释放显然不需要的Ca 2+通道子集;降低Na+通道激活阈值;并减缓Na+通道失活。δ/ω-plectoxin-Pt 1a通过延长突触前神经递质的释放而增强突触传递，其对Na+和Ca ~（2+）通道的作用可能协同维持终末兴奋性。
The venom of spider Plectreurys tristis contains a variety of peptide toxins that selectively target neuronal ion channels. O-palmitoylation of a threonine or serine residue, along with a characteristic and highly constrained disulfide bond structure, are hallmarks of a family of toxins found in this venom. Here, we report the isolation and characterization of a new toxin, δ/ω-plectoxin-Pt1a, from this spider venom. It is a 40 amino acid peptide containing an O-palmitoylated Ser-39. Analysis of δ/ω-plectoxin-Pt1a cDNA reveals a small precursor containing a secretion signal sequence, a 14 amino acid N-terminal propeptide, and a C-terminal amidation signal. The biological activity of δ/ω-plectoxin-Pt1a is also unique. It preferentially blocks a subset of Ca2+ channels that is apparently not required for neurotransmitter release; decreases threshold for Na+ channel activation; and slows Na+ channel inactivation. As δ/ω-plectoxin-Pt1a enhances synaptic transmission by prolonging presynaptic release of neurotransmitter, its effects on Na+ and Ca2+ channels may act synergistically to sustain the terminal excitability.
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DOI：
10.1074/jbc.m802140200
发表时间：
2008-09-05
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Greaves J;Salaun C;Fukata Y;Fukata M;Chamberlain LH
通讯作者：
Chamberlain LH
影响因子：
1.4
作者：
Bizzozero, OA
通讯作者：
Bizzozero, OA
影响因子：
2.5
作者：
Lee, D;Gurevitz, M;Adams, ME
通讯作者：
Adams, ME
影响因子：
4
作者：
Loane, David J.;Lima, Pedro A.;Marrion, Neil V.
通讯作者：
Marrion, Neil V.
影响因子：
2.5
作者：
Marley, Richard;Baines, Richard A.
通讯作者：
Baines, Richard A.