USP48减轻雄性小鼠骨癌疼痛并调节脊髓神经元中MrgC的稳定性

USP48 alleviates bone cancer pain and regulates MrgC stabilization in spinal cord neurons of male mice

作者信息Jiacheng Yu, Bailing Hou, Yulin Huang, Xiaoyu Wang, Yue Qian, Ying Liang, Xiaoping Gu, Zhengliang Ma, Yue Sun
PMID36864656
发布时间2023-07
DOI10.1002/ejp.2102

实验完整度

高

该研究包含体内动物模型(BCP小鼠)和体外细胞实验(N2a细胞),并进行了功能验证(疼痛行为学)和机制验证(免疫共沉淀、泛素化分析等),满足高完整度要求。

摘要

Background: Ubiquitin-mediated degradation of the Mas-related G protein-coupled receptor C (MrgC) reduces the number of receptors. However, the specific deubiquitinating enzyme antagonize this process has not been reported. In this study, we investigated the effect of ubiquitin-specific protease-48 (USP48) on bone cancer pain (BCP) and its effect on MrgC. Methods: A mouse model of BCP was established. BCP behaviours of mice were assessed after intrathecal injection of adeno-associated virus (AAV)-USP48. USP48 and MrgC interactions were studied by immunoprecipitation. Overexpression and knockdown of USP48 were conducted in N2a cells to investigate the effect of USP48 on MrgC receptor number and ubiquitination. Results: Spinal cord level USP48 expression was reduced in mice with BCP. Intrathecal injection of AAV-USP48 increased paw withdrawal mechanical threshold and reduced spontaneous flinching in mice. In N2a cells, there were increased number of MrgC receptors after overexpression of USP48 and decreased number of MrgC receptors after knockdown of USP48. USP48 interacted with MrgC and overexpression of USP48 altered the level of ubiquitination of MrgC. Conclusion: USP48 antagonizes ubiquitin-mediated autophagic degradation of MrgC and alleviates BCP in a murine animal model. Our findings may provide a new perspective for the treatment of BCP. Significance: Our finding may provide an important theoretical basis as well as an intervention target for clinical development of drugs for BCP.

研究路径

按研究推进顺序梳理实验设计、验证步骤与关键观察。

1

建立骨癌疼痛模型并评估疼痛行为

建立稳定的骨癌疼痛小鼠模型,并验证模型是否成功以及疼痛行为的变化。

将NCTC2472骨肉瘤细胞注入小鼠右侧股骨骨髓腔建立BCP模型,通过HE染色观察骨组织破坏,并通过测量PWMT和NSF评估疼痛行为。

2

检测USP48和MrgC的表达及定位

明确在骨癌疼痛过程中,脊髓中USP48和MrgC的表达变化以及USP48的细胞定位。

通过Western blotting和RT-qPCR检测不同时间点脊髓组织中USP48和MrgC的表达,通过免疫荧光染色观察USP48在脊髓背角的表达和细胞定位。

3

脊髓神经元过表达USP48的体内功能验证

验证在脊髓神经元中过表达USP48是否能缓解骨癌疼痛。

在BCP模型建立前21天,通过鞘内注射AAV-USP48或AAV-NC,然后通过Western blotting检测USP48表达,并通过疼痛行为学测试评估疼痛缓解效果。

4

验证USP48对MrgC蛋白水平的影响及相互作用

明确USP48是否影响MrgC蛋白水平以及两者是否存在直接相互作用。

通过Western blotting检测过表达或敲低USP48后MrgC蛋白的变化;在脊髓组织和N2a细胞中进行免疫共沉淀验证内源和外源USP48与MrgC的相互作用。

5

探究USP48对MrgC泛素化及降解途径的调控

阐明USP48是否通过去泛素化影响MrgC的稳定性和降解途径。

使用CHX追踪实验检测MrgC蛋白半衰期;通过表达不同的泛素突变体进行免疫共沉淀分析USP48影响的泛素链类型;使用不同的降解途径抑制剂处理N2a细胞,探究MrgC的降解方式。

研究方法

按研究目的归类文中使用的方法,便于定位所需技术。

产品清单

实验环节名称品牌货号
C3H/HeNCrl小鼠北京维通利华实验动物技术有限公司--
Neuro-2a (N2a)细胞American Type Culture Collection--
DMEM培养基BI--
胎牛血清Gibco--
青霉素Gibco--
链霉素Gibco--
Lipofectamine 3000转染试剂Thermo Fisher Scientific--
α-MEM培养基Thermo Fisher Scientific--
NCTC2472细胞American Type Culture Collection--
AAV-USP48--NM_130879
AAV-NC----
anti-USP48抗体Abcamab72226
anti-Iba1抗体Wako019-19741
anti-GFAP抗体Cell Signalling Tech80788
anti-NeuN抗体Abcam--
Alexa 488偶联山羊抗兔二抗InvitrogenA32731
Alexa 594偶联山羊抗小鼠二抗InvitrogenA-11005
DAPIAbcam--
M-PER哺乳动物蛋白提取试剂ThermoFisher--
BCA蛋白定量试剂盒----
anti-MrgC抗体InvitrogenPA5-89019
anti-β-Actin抗体Biossbs-0061R
anti-Flag抗体Cell Signalling Tech14793
anti-Myc抗体Cell Signalling Tech2276
anti-HA抗体Cell Signalling Tech3724
山羊抗兔二抗BeyotimeA0208
山羊抗小鼠二抗BeyotimeA0216
增强化学发光试剂Vazyme--
anti-USP48抗体Proteintech12076-1-AP
anti-IgG抗体BeyotimeA7016
Protein A/G磁珠Beyotime--
anti-Myc磁珠BeyotimeP2118
Trizol试剂Invitrogen--
HiScript II qRT SuperMix逆转录试剂Vazyme--
ChamQ Universal SYBR qPCR预混液Vazyme--
QuantStudio™ 5食品安全实时荧光定量PCR系统Thermo Fisher Scientific--
EDTA脱钙液----
von Frey纤毛Stoelting--
SPSS 25.0IBM--

关键环节

汇总复现实验时建议重点确认的条件及原文阅读提示。

环节核对要点
动物模型建立
小鼠品系(C3H/HeNCrl)、性别(雄性)、年龄(4-6周龄)、体重(23±2g)、肿瘤细胞类型(NCTC2472)及数量(2×10^5)、注射体积(20μL)
阅读提示:Materials and Methods, 2.1 Animals和2.3 Establishment of BCP model
鞘内注射
AAV血清型(9型)、注射体积(5μL)、注射时间(BCP建模前21天)、注射位点(L5-L6椎间隙)
阅读提示:Materials and Methods, 2.4 Intrathecal injection
细胞培养与转染
细胞系(N2a)、培养基(90% DMEM+10% FBS+100U/mL青霉素+100μg/mL链霉素)、转染试剂(Lipofectamine 3000)、质粒量(3-4.5μg)、siRNA浓度(100nM)、转染时间(48小时)
阅读提示:Materials and Methods, 2.2 Cell culture and transfection
疼痛行为学评估
评估时间点(术前1天及术后3,7,10,14,21,28天)、von Frey纤毛强度范围(0.16, 0.4, 0.6, 1.0, 1.4, 2.0g)、每次刺激测试次数(5次)、自发退缩计数时间(2分钟)
阅读提示:Materials and Methods, 2.5 Paw withdrawal mechanical threshold和2.6 Spontaneous flinching test
蛋白检测与相互作用
蛋白提取试剂(M-PER)、BCA定量试剂盒、PVDF膜、一抗及稀释比例(如anti-USP48 1:1000, anti-MrgC 1:1000)、IP抗体用量(4μg)、磁珠用量(1:20)
阅读提示:Materials and Methods, 2.8 Western blotting和2.9 Immunoprecipitation