Photoaffinity labeling of insect nicotinic acetylcholine receptors with a novel [(3)H]azidoneonicotinoid.
Photoaffinity labeling of insect nicotinic acetylcholine receptors with a novel [(3)H]azidoneonicotinoid.
复制标题
用新型[(3)H]叠氮烟碱类化合物对昆虫烟碱乙酰胆碱受体进行光亲和标记。
DOI：
10.1046/j.1471-4159.2001.00518.x
复制
发表时间：
2001
影响因子：
4.7
通讯作者：
Casida,JE
中科院分区：
文献类型：
--
作者：
Tomizawa,M;Wen,Z;Chin,HL;Morimoto,H;Kayser,H;Casida,JE
The nicotinic acetylcholine receptor (nAChR) is a ligand‐gated ion channel in the insect CNS and a target for major insecticides. Here we use photoaffinity labeling to approach the functional architecture of insect nAChRs. Two candidate 5‐azido‐6‐chloropyridin‐3‐yl photoaffinity probes are evaluated for their receptor potencies: azidoneonicotinoid (AzNN) with an acyclic nitroguanidine moiety; azidodehydrothiacloprid. Compared to their non‐azido parents, both probes are of decreased potencies atDrosophila(fruit fly) andMusca(housefly) receptors but AzNN retains full potency at theMyzus(aphid) receptor. [3H]AzNN was therefore radiosynthesized at high specific activity (84 Ci/mmol) as a novel photoaffinity probe. [3H]AzNN binds to a single high‐affinity site inMyzusthat is competitively inhibited by imidacloprid and nicotine and further characterized as to its pharmacological profile with various nicotinic ligands. [3H]AzNN photoaffinity labeling ofMyzusandHomalodisca(leafhopper) detects a single radiolabeled peak in each case displaceable with imidacloprid and nicotine and with molecular masses corresponding to ∼45 and ∼56 kDa, respectively. The photoaffinity‐labeled receptor in bothDrosophilaandMuscahas imidacloprid‐ and nicotine‐sensitive profiles and migrates at ∼66 kDa. These photoaffinity‐labeled polypeptides are considered to be the insecticide‐binding subunits of native insect nAChRs.
