Intriguing olfactory proteins from the yellow fever mosquito, Aedes aegypti
Intriguing olfactory proteins from the yellow fever mosquito, Aedes aegypti
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DOI：
10.1007/s00114-004-0551-7
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发表时间：
2004-09-01
影响因子：
--
通讯作者：
Leal, WS
中科院分区：
文献类型：
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作者：
Ishida, Y;Chen, AM;Leal, WS
从埃及伊蚊（Aedesaegypti）中分离到4个触角特异蛋白（AaegOBP 1、AaegOBP 2、AaegOBP 3和AaegASP 1），并克隆了它们的全长cDNA。RT-PCR表明，它们在雌性中表达，在较小程度上，在雄性触角中表达，但在对照组织（腿）中不表达。AaegOBP 1和AaegOBP 3在半胱氨酸间隔模式和序列上与先前鉴定的蚊子气味结合蛋白（OBP）具有显著的相似性。分离的蛋白质中的两个具有总共八个半胱氨酸残基。半胱氨酸残基和氨基酸序列的间隔模式的相似性，以前确定的嗅觉蛋白，表明富含半胱氨酸的蛋白质（AaegOBP 2）是一个OBP。另一个（AaegASP 1）不属于任何已知的OBP组。结构分析表明，AaegOBP 2中的六个半胱氨酸残基以与OBP中先前已知的半胱氨酸配对相似的模式连接，即，Cys-24-Cys-55、Cys-51-Cys-104、Cys-95-Cys-113。额外的二硫桥Cys-38-Cys-125将蛋白质的延伸C-末端区段编织成预测的α 2-螺旋。如圆二色性（CD）光谱所示，额外的刚性似乎阻止了在低pH下C-末端α-螺旋的预测形成。
Four antennae-specific proteins (AaegOBP1, AaegOBP2, AaegOBP3, and AaegASP1) were isolated from the yellow fever mosquito, Aedes aegypti and their full-length cDNAs were cloned. RT-PCR indicated that they are expressed in female and, to a lesser extent, in male antennae, but not in control tissues (legs). AaegOBP1 and AaegOBP3 showed significant similarity to previously identified mosquito odorant-binding proteins (OBPs) in cysteine spacing pattern and sequence. Two of the isolated proteins have a total of eight cysteine residues. The similarity of the spacing pattern of the cysteine residues and amino acid sequence to those of previously identified olfactory proteins suggests that one of the cysteine-rich proteins (AaegOBP2) is an OBP. The other (AaegASP1) did not belong to any group of known OBPs. Structural analyses indicate that six of the cysteine residues in AaegOBP2 are linked in a similar pattern to the previously known cysteine pairing in OBPs, i.e., Cys-24-Cys-55, Cys-51-Cys-104, Cys-95-Cys-113. The additional disulfide bridge, Cys-38-Cys-125, knits the extended C-terminal segment of the protein to a predicted alpha2-helix. As indicated by circular dichroism (CD) spectra, the extra rigidity seems to prevent the predicted formation of a C-terminal alpha-helix at low pH.