Spatio-temporal dynamics of the egg-laying-inducing peptides during an egg-laying cycle:: a semiquantitative matrix-assisted laser desorption/ionization mass spectrometry approach
Spatio-temporal dynamics of the egg-laying-inducing peptides during an egg-laying cycle:: a semiquantitative matrix-assisted laser desorption/ionization mass spectrometry approach
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DOI：
10.1111/j.1471-4159.2004.02353.x
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发表时间：
2004-05-01
影响因子：
4.7
通讯作者：
Li, KW
中科院分区：
文献类型：
--
作者：
Jiménez, CR;ter Maat, A;Li, KW
淡水蜗牛（lynaea滞螺）神经内分泌尾背细胞（CDC）系统多肽的活性依赖性释放调节产卵及相关行为。在这项研究中，我们优化了一种基于质谱的方法来研究主要来自CDC激素前体的肽在体外产蛋周期和CDC排出过程中的时空动态。利用基质辅助激光解吸/电离质谱（MALDI-MS）进行的半定量肽质量分析表明，产蛋期间，大脑连接（COM）的神经血管区大量消耗肽，而CDC体细胞中存在肽储备池，这些肽被运输到COM以恢复肽水平。体外诱导放电过程中，COM中CDC肽的消耗与它们的释放有关。此外，释放物的MALDI-MS显示羧基末端肽广泛截断。最后，两个不被CDC激素前体编码的新肽1788和5895 Da也表现出与CDC肽相似的时间定量变化。对1788 Da的肽段进行串联质谱测序，得到新的序列HF(FH)FYGPYDVFQRDVamide。总之，这暗示了一套比以前预期的更复杂的CDC肽来调节产卵。
The activity-dependent release of peptides from the neuroendocrine caudodorsal cell (CDC) system of the freshwater snail Lymnaea stagnalis regulates egg laying and related behaviors. In this study, we optimized a mass spectrometry-based approach to study the spatio-temporal dynamics of peptides that are largely derived from the CDC hormone precursor during an egg-laying cycle and a CDC discharge in vitro. Semi-quantitative peptide mass profiling using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) indicated a massive depletion of peptides from the neurohemal area in the cerebral commissure (COM) during egg laying and the existence of a reserve pool of peptides in the CDC somata that were transported to the COM to restore peptide levels. The depletion of CDC peptides from the COM was correlated to their release during an induced electrical discharge in vitro. Moreover, MALDI-MS of the releasate revealed extensive truncation of the carboxyl terminal peptide. Finally, two novel peptides of 1788 and 5895 Da, not encoded by the CDC hormone precursor, also exhibited temporal quantitative changes similar to those of CDC peptides. Sequencing of the peptide of 1788 Da by tandem mass spectrometry yielded the novel sequence HF(FH)FYGPYDVFQRDVamide. Together, this implicates a more complex set of CDC peptides for the regulation of egg laying than previously anticipated.