目的探讨1例致心律失常性右室心肌病(ARVC)患儿的临床特征与遗传学病因。方法选取2022年8月23日于福建省儿童医院就诊的1例ARVC患儿作为研究对象。采集患儿的相关临床资料,抽取患儿及其父母的外周静脉血样,应用全外显子组测序(WES)对患...目的探讨1例致心律失常性右室心肌病(ARVC)患儿的临床特征与遗传学病因。方法选取2022年8月23日于福建省儿童医院就诊的1例ARVC患儿作为研究对象。采集患儿的相关临床资料,抽取患儿及其父母的外周静脉血样,应用全外显子组测序(WES)对患儿进行基因检测,采用Sanger测序进行家系验证,并对候选变异进行致病性分析。结果本研究患儿为6岁男性,临床表现为全身浮肿、全心扩大、室间隔及室壁运动普遍性减弱、左心室舒张及收缩功能减低、右心室收缩功能减低。WES检测结果提示患儿携带PKP2基因c.119_122del(p.Leu40Argfs Ter 71)杂合移码变异与c.1978G>A(p.Gly660Arg)杂合错义变异。经Sanger测序验证,上述变异分别遗传自患儿父亲与母亲。PKP2基因c.119_122del变异在1000 Genomes、gnomAD及ExAC等数据库中未见收录;经SWISS-MODEL与PyMOL在线软件分析可能导致PKP2蛋白截短;根据美国医学遗传学与基因组学学会(ACMG)与ClinGen联合制订的相关指南,该变异被判定为可能致病性变异。PKP2基因c.1978G>A变异在1000 Genomes、gnomAD及ExAC等数据库中未见收录;应用REVEL、SIFT、CADD、MutationTaster及PolyPhen-2等在线软件预测为有害变异;经T-coffee与ESPript v3.0在线服务器分析,该变异位点编码氨基酸在不同物种中高度保守;经SWISS-MODEL与PyMOL在线服务器分析,该变异可能影响蛋白功能;根据ACMG与ClinGen联合制订的相关指南,该变异被判定为可能致病性变异。结论PKP2基因c.119_122del(p.Leu40Argfs Ter 71)杂合移码变异与c.1978G>A(p.Gly660Arg)杂合错义变异可能是本研究ARVC患儿的遗传学病因。上述发现拓宽了PKP2基因的变异谱,为ARVC患者的诊断提供了依据。展开更多
Background:Dysfunction of the gap junction channel protein connexin 43(Cx43)contributes to myocardial ischemia/reperfusion(I/R)-induced ventricular arrhythmias.Cx43 can be regulated by small ubiquitin-like modifier(SU...Background:Dysfunction of the gap junction channel protein connexin 43(Cx43)contributes to myocardial ischemia/reperfusion(I/R)-induced ventricular arrhythmias.Cx43 can be regulated by small ubiquitin-like modifier(SUMO)modification.Protein inhibitor of activated STAT Y(PIASy)is an E3 SUMO ligase for its target proteins.However,whether Cx43 is a target protein of PIASy and whether Cx43 SUMOylation plays a role in I/R-induced arrhythmias are largely unknown.Methods:Male Sprague-Dawley rats were infected with PIASy short hairpin ribonucleic acid(shRNA)using recombinant adeno-associated virus subtype 9(rAAV9).Two weeks later,the rats were subjected to 45 min of left coronary artery occlusion followed by 2 h reperfusion.Electrocardiogram was recorded to assess arrhythmias.Rat ventricular tissues were collected for molecular biological measurements.Results:Following 45 min of ischemia,QRS duration and QTc intervals statistically significantly increased,but these values decreased after transfecting PIASy shRNA.PIASy downregulation ameliorated ventricular arrhythmias induced by myocardial I/R,as evidenced by the decreased incidence of ventricular tachycardia and ventricular fibrillation,and reduced arrythmia score.In addition,myocardial I/R statistically significantly induced PIASy expression and Cx43 SUMOylation,accompanied by reduced Cx43 phosphorylation and plakophilin 2(PKP2)expression.Moreover,PIASy downregulation remarkably reduced Cx43 SUMOylation,accompanied by increased Cx43 phosphorylation and PKP2 expression after I/R.Conclusion:PIASy downregulation inhibited Cx43 SUMOylation and increased PKP2 expression,thereby improving ventricular arrhythmias in ischemic/reperfused rats heart.展开更多
文摘目的探讨1例致心律失常性右室心肌病(ARVC)患儿的临床特征与遗传学病因。方法选取2022年8月23日于福建省儿童医院就诊的1例ARVC患儿作为研究对象。采集患儿的相关临床资料,抽取患儿及其父母的外周静脉血样,应用全外显子组测序(WES)对患儿进行基因检测,采用Sanger测序进行家系验证,并对候选变异进行致病性分析。结果本研究患儿为6岁男性,临床表现为全身浮肿、全心扩大、室间隔及室壁运动普遍性减弱、左心室舒张及收缩功能减低、右心室收缩功能减低。WES检测结果提示患儿携带PKP2基因c.119_122del(p.Leu40Argfs Ter 71)杂合移码变异与c.1978G>A(p.Gly660Arg)杂合错义变异。经Sanger测序验证,上述变异分别遗传自患儿父亲与母亲。PKP2基因c.119_122del变异在1000 Genomes、gnomAD及ExAC等数据库中未见收录;经SWISS-MODEL与PyMOL在线软件分析可能导致PKP2蛋白截短;根据美国医学遗传学与基因组学学会(ACMG)与ClinGen联合制订的相关指南,该变异被判定为可能致病性变异。PKP2基因c.1978G>A变异在1000 Genomes、gnomAD及ExAC等数据库中未见收录;应用REVEL、SIFT、CADD、MutationTaster及PolyPhen-2等在线软件预测为有害变异;经T-coffee与ESPript v3.0在线服务器分析,该变异位点编码氨基酸在不同物种中高度保守;经SWISS-MODEL与PyMOL在线服务器分析,该变异可能影响蛋白功能;根据ACMG与ClinGen联合制订的相关指南,该变异被判定为可能致病性变异。结论PKP2基因c.119_122del(p.Leu40Argfs Ter 71)杂合移码变异与c.1978G>A(p.Gly660Arg)杂合错义变异可能是本研究ARVC患儿的遗传学病因。上述发现拓宽了PKP2基因的变异谱,为ARVC患者的诊断提供了依据。
基金National Natural Science Foundation of China(Nos.81770824 and 81470251)
文摘Background:Dysfunction of the gap junction channel protein connexin 43(Cx43)contributes to myocardial ischemia/reperfusion(I/R)-induced ventricular arrhythmias.Cx43 can be regulated by small ubiquitin-like modifier(SUMO)modification.Protein inhibitor of activated STAT Y(PIASy)is an E3 SUMO ligase for its target proteins.However,whether Cx43 is a target protein of PIASy and whether Cx43 SUMOylation plays a role in I/R-induced arrhythmias are largely unknown.Methods:Male Sprague-Dawley rats were infected with PIASy short hairpin ribonucleic acid(shRNA)using recombinant adeno-associated virus subtype 9(rAAV9).Two weeks later,the rats were subjected to 45 min of left coronary artery occlusion followed by 2 h reperfusion.Electrocardiogram was recorded to assess arrhythmias.Rat ventricular tissues were collected for molecular biological measurements.Results:Following 45 min of ischemia,QRS duration and QTc intervals statistically significantly increased,but these values decreased after transfecting PIASy shRNA.PIASy downregulation ameliorated ventricular arrhythmias induced by myocardial I/R,as evidenced by the decreased incidence of ventricular tachycardia and ventricular fibrillation,and reduced arrythmia score.In addition,myocardial I/R statistically significantly induced PIASy expression and Cx43 SUMOylation,accompanied by reduced Cx43 phosphorylation and plakophilin 2(PKP2)expression.Moreover,PIASy downregulation remarkably reduced Cx43 SUMOylation,accompanied by increased Cx43 phosphorylation and PKP2 expression after I/R.Conclusion:PIASy downregulation inhibited Cx43 SUMOylation and increased PKP2 expression,thereby improving ventricular arrhythmias in ischemic/reperfused rats heart.
