Human KCNQ5 de novo mutations underlie epilepsy and intellectual disability.
Human KCNQ5 de novo mutations underlie epilepsy and intellectual disability.
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人类 KCNQ5 从头突变是癫痫和智力障碍的基础。
DOI：
10.1152/jn.00509.2021
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发表时间：
2022
影响因子：
2.5
通讯作者：
Helb
中科院分区：
文献类型：
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作者：
Wei,AguanD;Wakenight,Paul;Zwingman,TheresaA;Bard,AngelaM;Sahai,Nikhil;Willemsen,MarjoleinH;Schelhaas,HeleniusJ;Stegmann,AlexanderPA;Verhoeven,JudithS;deMan,StellaA;Wessels,MarjaW;Kleefstra,Tjitske;Shinde,DeepaliN;Helb
通过全外显子组测序，我们在运动/语言发育迟缓、智力残疾（ID）和/或癫痫儿童中发现了6种新的人类KCNQ 5变异体。这些突变体包括两个无义突变和四个错义突变，它们与四个先前发现的KCNQ 5错义突变体一起，在HEK 293/CHO细胞中通过电生理学进行了功能表征（Lehman A，Thouta S，Mancini GM，Naidu S，货车Slegtenhorst M，McWalter K，Person R，Mwenifumbo J，Salvarinova R; CAUSES研究; EPGEN研究; Guella I，McKenzie MB，Datta A，Connolly MB，Kalkhoran SM，Pkartko D，Friedman JM，Farrer MJ，Demos M，Desai S，Claydon T.Am J Genet101：65-74，2017）.令人惊讶的是，所有八个错义变体由于激活的超极化电压依赖性或失活动力学减慢而导致功能获得（GOF），而两个无义变体被证实为功能丧失（LOF）。一个严重的GOF等位基因（P369 T）进行了测试，发现扩展到异聚KCNQ 5/3通道的显性GOF效应。临床表现与KCNQ 5通道门控改变相关：轻度表现为LOF或电压依赖性较小的GOF偏移[半最大传导时的电压变化（ΔV50）= 10 - 15 mV]，重度表现为电压依赖性较大的GOF偏移（ΔV50= 10 - 30 mV）。为了检查LOF致病性，用CRISPR/Cas9创建了两个Kcnq 5LOF小鼠系。两条线都表现出处理和热诱导的癫痫发作和异常皮层脑电图符合癫痫样活动。因此，我们的研究提供了体内KCNQ 5LOF致病性的证据，并加强了LOF和GOF突变对全球儿科神经功能缺损的贡献，包括ID/epilepsy.NEW & NOTEWORTH 6个新的从头人类KCNQ 5variants从神经发育迟缓，智力残疾和/或癫痫的儿童中鉴定出来。这些变异体的表达沿着来自相似队列的4个先前鉴定的KCNQ 5变异体，揭示了GOF钾通道在激活和/或延迟失活动力学的V 50中负移。GOF扩展到KCNQ 5/3异聚体通道，使这些通道成为杂合子原发患者的主要通道。Kcnq 5LOF小鼠表现出癫痫发作，与体内致病性一致。
We identified six novel de novo humanKCNQ5variants in children with motor/language delay, intellectual disability (ID), and/or epilepsy by whole exome sequencing. These variants, comprising two nonsense and four missense alterations, were functionally characterized by electrophysiology in HEK293/CHO cells, together with four previously reportedKCNQ5missense variants (Lehman A, Thouta S, Mancini GM, Naidu S, van Slegtenhorst M, McWalter K, Person R, Mwenifumbo J, Salvarinova R; CAUSES Study; EPGEN Study; Guella I, McKenzie MB, Datta A, Connolly MB, Kalkhoran SM, Poburko D, Friedman JM, Farrer MJ, Demos M, Desai S, Claydon T.Am J Hum Genet101: 65–74, 2017). Surprisingly, all eight missense variants resulted in gain of function (GOF) due to hyperpolarized voltage dependence of activation or slowed deactivation kinetics, whereas the two nonsense variants were confirmed to be loss of function (LOF). One severe GOF allele (P369T) was tested and found to extend a dominant GOF effect to heteromeric KCNQ5/3 channels. Clinical presentations were associated with altered KCNQ5 channel gating: milder presentations with LOF or smaller GOF shifts in voltage dependence [change in voltage at half-maximal conduction (ΔV50) = ∼−15 mV] and severe presentations with larger GOF shifts in voltage dependence (ΔV50= ∼−30 mV). To examine LOF pathogenicity, twoKcnq5LOF mouse lines were created with CRISPR/Cas9. Both lines exhibited handling- and thermal-induced seizures and abnormal cortical EEGs consistent with epileptiform activity. Our study thus provides evidence for in vivoKCNQ5LOF pathogenicity and strengthens the contribution of both LOF and GOF mutations to global pediatric neurological impairment, including ID/epilepsy.NEW & NOTEWORTHYSix novel de novo humanKCNQ5variants were identified from children with neurodevelopmental delay, intellectual disability, and/or epilepsy. Expression of these variants along with four previously reportedKCNQ5variants from a similar cohort revealed GOF potassium channels, negatively shifted inV50of activation and/or delayed deactivation kinetics. GOF is extended to KCNQ5/3 heteromeric channels, making these the predominant channels affected in heterozygous de novo patients.Kcnq5LOF mice exhibited seizures, consistent with in vivo pathogenicity.