S66 Deletion of mesenchymal Gaq/11 results in abnormal lung development and renal abnormalities: a transgenic mouse study
S66 Deletion of mesenchymal Gaq/11 results in abnormal lung development and renal abnormalities: a transgenic mouse study
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S66 间充质 Gaq/11 缺失导致肺发育异常和肾脏异常：转基因小鼠研究
DOI：
10.1136/thorax-2018-212555.72
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Goodwin A
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文献类型：
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作者：
Goodwin A
研究背景发育性肺疾病可导致显著的死亡率和终身患病率。目前还没有恢复正常器官形成的治疗方法，但对肺发育的分子机制的研究可能会确定治疗靶点。正常的肺发育需要多种细胞类型的协调活动，并且与肿瘤有着共同的信号通路。周细胞和肌成纤维细胞分别通过其在血管形成和肺泡形成中的作用对肺发育至关重要。G蛋白Gα q和Gα11（Gαq/11）是生理和病理生理信号通路的关键组分，但间充质Gαq/11信号在肺发育中的作用尚不清楚。方法G αqfloxed，Gα 11敲除纯合子小鼠（Gnaqfl/fl; Gna 11-/-）与Pdgfrb-Cre±小鼠杂交，产生Pdgfrb表达细胞（周细胞、肌成纤维细胞）中缺乏Gαq/11的后代。用ClariomTMD小鼠微阵列芯片（Affytron）和Partek Genomics Suite 6.6软件分析来自Gαq/11缺陷小鼠和对照小鼠的全肺RNA。结果间充质Gαq/11基因敲除小鼠肺组织学上与对照组相比，肺泡腔扩大，肺泡壁增厚，次级隔减少，弹性纤维减少（p<0 0 5，n=4），肺泡化异常。此外，间充质Gαq/11基因敲除肺的外周肺血管增厚表明肺血管异常。全肺RNA微阵列显示，线粒体关键功能基因mt-Tk和几种已知调节血管生成、增殖和细胞分化的miRNAs表达下调与对照相比，间充质Gαq/11敲除肺中miR-684、miRlet 7 f-1、miR 186的表达（p<0.05，倍数变化>1.5）。间充质Gαq/11基因敲除小鼠的高基因表达变异性可能提示表型的变异，这些发现需要进一步验证。间充质Gα q/11基因敲除小鼠的肾小管上皮细胞在肾脏组织学上发现肿瘤性过度增殖，提示间充质Gα q/11在肿瘤抑制中的作用。调节弹性蛋白沉积、线粒体功能、血管生成和增殖作为候选机制。间充质Gαq/11信号调节肾上皮细胞增殖，突出了共同的发育和恶性途径。这是第一个产生间充质Gαq/11基因敲除小鼠的研究，进一步的研究可能会确定发育性肺病的治疗靶点。
BackgroundDevelopmental lung diseases cause significant mortality and lifelong morbidity. There is no treatment to restore normal organogenesis, but research into the molecular mechanisms of lung development may identify therapeutic targets.Normal lung development requires the coordinated activity of numerous cell types, and has shared signalling pathways with neoplasia. Pericytes and myofibroblasts are essential for lung development, through their roles in vascularisation and alveolarisation, respectively. The G proteins Gαqand Gα11(Gαq/11) are key components of physiological and pathophysiological signalling pathways, but the role of mesenchymal Gαq/11signalling in lung development is unknown.MethodsGαqfloxed, Gα11knockout homozygous mice (Gnaqfl/fl;Gna11-/-) were crossed with Pdgfrb-Cre±mice to generate offspring lacking Gαq/11in Pdgfrb-expressing cells (pericytes, myofibroblasts). Organs were harvested from 2 week old mice for histological and biochemical analyses.Whole lung RNA from Gαq/11-deficient and control mice was analysed using ClariomTMD Mouse microarray chips (Affymetrix) and Partek Genomics Suite 6.6 software. Differentially expressed genes were considered of interest with p≤0.05 and fold change ±1.5.ResultsMesenchymal Gαq/11-knockout mouse lungs had enlarged airspaces, thickened alveolar walls, fewer secondary septae, and fewer elastin fibres on histology compared with controls (p<0.05, n=4), demonstrating abnormal alveolarisation. Additionally, thickened peripheral pulmonary vessels in mesenchymal Gαq/11-knockout lungs indicated a pulmonary vascular abnormality.Whole lung RNA microarray demonstrated downregulation of mt-Tk, a key mitochondrial function gene, and several miRNAs known to regulate angiogenesis, proliferation, and cellular differentiation (miR-684, miRlet7f-1, miR186) in mesenchymal Gαq/11-knockout lungs compared with controls (p<0.05, fold change >1.5). High gene expression variability in mesenchymal Gαq/11-knockout lungs may indicate variations in phenotype, and these findings require validation.Neoplastic hyperproliferation of the medullary tubular epithelium in mice lacking mesenchymal Gαq/11was found on renal histology, suggesting a role for mesenchymal Gαq/11in tumour suppression.ConclusionGαq/11signalling in Pdgfrb-positive cells is essential for normal lung development, with regulation of elastin deposition, mitochondrial function, angiogenesis, and proliferation as candidate mechanisms. Mesenchymal Gαq/11signalling regulates renal epithelial proliferation, highlighting a shared developmental and malignant pathway. This is the first study to generate mesenchymal Gαq/11-knockout mice, further investigation of which may identify therapeutic targets for developmental lung disease.