棉铃虫感觉神经元膜蛋白基因克隆和表达

从棉铃虫Helicoverpa armigera触角中克隆了一条全长1 690 bp的cDNA序列，该序列阅读框全长1 572 bp，编码523个氨基酸残基，序列中有2个跨膜区，具有昆虫感觉神经元膜蛋白（sensory neuron membrane protein， SNMP）的典型特征。SNMP与已报道的其他昆虫的感觉神经元蛋白的氨基酸序列有很高的同源性。半定量RT-PCR研究结果显示，SNMP在棉铃虫中不仅在触角中表达，也在去掉触角的头、足中表达。但是在触角中的表达量最高，在雌雄触角中的表达量差异不显著。在喙、下颚须和下唇须中也有表达。SNMP在卵、蛹和成虫体内也都有表达，但在卵中表达量相对较低。将SNMP编码区克隆到表达载体pET21b中，成功地进行了原核表达，表达出带有6个组氨酸标签的重组蛋白。

Cloning and expression of sensory neuron membrane protein in Helicoverpa armigera

A full-length cDNA encoding sensory neuron membrane protein (SNMP) was cloned from antennae of Helicoverpa armigera. The open reading-frame of SNMP was 1 572 bp, encoding 523 amino acid residues. There were two putative transmembrane domains, which is the typical characteristic of SNMPs. And it also shared high identity with sensory neuron membrane proteins from other insects. Semi-quantitative RT-PCR analysis showed that SNMP was not only expressed in antennae, but also in head (excluding antennae) and legs of H. armigera. However, its expression in antennae was much higher than that in head and legs. There was no obvious difference between the expression in male antennae and that in female antennae. Moreover, it was also expressed in labial palpus, maxillary palpus and proboscis. SNMP was expressed in egg, the 10th-day pupa and imago, but expressed relatively low in egg. The SNMP coding region was cloned into the expression vector pET21b, and the recombinant SNMP protein with six-His tag was successfully expressed in the bacteria.