Resistance to inhibitors of cholinesterase (RIC) −3 promotes the maturation (folding and assembly) of neuronal nicotinic acetylcholine receptors (nAChRs) as a molecular chaperone. The modulation effects of RIC-3 on homomeric α7 nAChRs are always positive, but its effects on heteromeric subtypes are inconsistent among reports. In this study, five RIC-3 isoforms were identified from Locusta migratoria. Four isoforms showed obvious effects on hybrid receptor Locα1/rβ2 expressed in Xenopus oocytes. As a representative, the co-expression of RIC-3v4 exhibited the decreased agonist responses (I_max) on oocytes, lower specific [³H]epibatidine binding (B_max) on plasma membrane protein (PMP), and reduced subunit levels in PMP, which showed that the mature Locα1/rβ2 on the plasma membrane was decreased by the co-expression of RIC-3. In contrast, the [³H]epibatidine binding and mature Locα1/rβ2 levels in the endoplasmic reticulum membrane protein (ERMP) were much increased when co-expressing with RIC-3v4. The [³H]epibatidine binding and mature Locα1/rβ2 levels in total membrane protein (TMP) gave the similar results as that in ERMP. Taking data together, the results showed that the co-expression of RIC-3 increased the mature Locα1/rβ2 receptor levels on ER of Xenopus oocytes, but these mature receptors were mostly kept on ER and suppressed to transport to plasma membrane.

对胆碱酯酶（RIC）-3抑制剂的抗性促进了作为分子伴侣的神经元烟碱型乙酰胆碱受体（nAChRs）的成熟（折叠和组装）。RIC-3对同型α7nAChRs的调节作用始终是积极的，但在报道中其对异聚体亚型的作用却不一致。在这项研究中，从东方蝗中鉴定出五种RIC-3同工型。四种同工型对非洲爪蟾卵母细胞中表达的杂合受体Locα1/rβ2具有明显的作用。作为代表，RIC-3v4的共表达在卵母细胞上显示出降低的激动剂反应（I _max），较低的特异性[ ³ H] epibatidine结合（B _max）和质膜蛋白（PMP）中亚基水平的降低，表明RIC-3的共表达降低了质膜上成熟Locα1/rβ2的表达。相反，当与RIC-3v4共表达时，内质网膜蛋白（ERMP）中的[ ³ H] epibatidine结合和成熟Locα1/rβ2水平大大增加。总膜蛋白（TMP）中的[ ³ H] epibatidine结合和成熟的Locα1/rβ2水平产生了与ERMP中相似的结果。综上所述，结果表明RIC-3的共表达增加了非洲爪蟾卵母细胞ER上成熟的Locα1/rβ2受体水平，但这些成熟受体大部分保留在ER上并被抑制转运至质膜。