Palmer Gregory C, Tran Truc, Duttlinger Amanda, Nichols Ruthann
Biological Chemistry Department, University of Michigan Medical School, Medical Science Research Building III, Ann Arbor, MI 48109-0606, USA.
J Insect Physiol. 2007 Nov;53(11):1125-33. doi: 10.1016/j.jinsphys.2007.06.001. Epub 2007 Jun 12.
We report that the drosulfakinin 0 (DSK 0; NQKTMSFNH2) structure and genomic organization are conserved. The DSK 0 C-terminus, SFNH2, is widely distributed in the animal kingdom suggesting it defines a novel peptide family. We also report the first description of DSK 0 activity. DSK 0, I (DSK I, FDDYGHMRFNH2), and II (DSK II, GGDDQFDDYGHMRFNH2) are encoded in sulfakinin (Dsk). Drosophila erecta, Drosophila sechellia, Drosophila simulans, and Drosophila yakuba shared 62.5-87.5% identity to Drosophila melanogaster DSK 0; Drosophila pseudoobscura shared 37.5% identity; numerous amino acids were one nucleotide different from a corresponding residue in D. melanogaster. DSK I and II were identical among the drosopholids. DSK 0 proteolytic processing sites were RR except D. yakuba contained KR and D. pseudoobscura contained HR, one nucleotide different from RR. DSK I and II processing sites were identical among the drosopholids. We established DSK 0 decreased adult (EC50=237nM and R(2)=0.941), but not larval gut contractions. DSK 0 exists in the central nervous system including the subesophageal ganglion and an abdominal ganglion. Peptide and genomic conservation, activity, and spatial and temporal distribution support the conclusion that DSK 0 plays diverse biological roles in drosopholids including regulating gut muscle contraction.
我们报告果蝇速激肽0（DSK 0；NQKTMSFNH2）的结构和基因组组织是保守的。DSK 0的C末端，即SFNH2，在动物界广泛分布，这表明它定义了一个新的肽家族。我们还首次描述了DSK 0的活性。DSK 0、I（DSK I，FDDYGHMRFNH2）和II（DSK II，GGDDQFDDYGHMRFNH2）由速激肽（Dsk）编码。果蝇 erecta、果蝇 sechellia、果蝇 simulans和果蝇 yakuba与黑腹果蝇DSK 0的序列一致性为62.5 - 87.5%；果蝇pseudoobscura的序列一致性为37.5%；许多氨基酸与黑腹果蝇的相应残基仅有一个核苷酸的差异。DSK I和II在果蝇类中是相同的。除了果蝇yakuba含有KR、果蝇pseudoobscura含有HR（与RR仅有一个核苷酸的差异）外，DSK 0的蛋白水解加工位点均为RR。DSK I和II的加工位点在果蝇类中是相同的。我们证实DSK 0可降低成虫（半数有效浓度EC50 = 237nM，决定系数R(2)=0.941）的肠道收缩，但对幼虫肠道收缩无影响。DSK 0存在于中枢神经系统，包括咽下神经节和一个腹神经节。肽和基因组的保守性、活性以及时空分布均支持以下结论：DSK 0在果蝇类中发挥多种生物学作用，包括调节肠道肌肉收缩。
