Expression and significance of HERG protein in Cajal interstitial cells of gallbladder tissue in patients with gallbladder stones / 中华肝胆外科杂志

Objective:To investigate the expression and significance of human ether-a-go-go related gene (HERG) protein in interstitial cells of Cajal (ICC) in patients with gallbladder stones.Methods:The gallbladder tissues of 60 patients with gallbladder diseases who underwent cholecystectomy from January 2018 to December 2020 in the Faculty of Hepato-Pancreato-Biliary Surgery, Chinese PLA General Hospital were collected, including 36 males and 24 females, aged (46.0±14.0) years. They were divided into two groups according to whether there were gallstones: gallstone group and control group (patients with gallbladder polyps and gallbladder adenomyosis), with 30 cases in each group. Color ultrasound was used to detect and calculate the gallbladder contraction rate. The neck, body and bottom tissues of the gallbladder were excised and sectioned. The expression of HERG protein and CD117 ( marker of ICC) was detected by immunofluorescence staining, immunohistochemistry and Western blot.Results:The gallbladder contraction rate in the gallstone group was (65.8±4.1)%, lower than that in the control group (73.8±5.3)%, with a statistically significant difference ( t=4.14, P<0.001). Immunohistochemistry showed that HERG protein was mainly distributed in the mucosal layer of gallbladder tissue, which was pale brown. The relative expression of HERG protein at the bottom of gallbladder in the gallstone group was (0.293±0.102), lower than that in the control group (0.694±0.059), with a statistically significant difference ( t=3.38, P=0.027). Immunofluorescence staining showed that HERG protein was mainly distributed in ICC of gallbladder epithelium. HERG protein expression in ICC at the bottom of gallbladder in gallstone group was lower than that in control group, while HERG protein expression at the neck and body of gallbladder had no significant difference. Conclusion:There are ICC and HERG protein in gallbladder tissue of patients with gallstone. The decrease of gallbladder contraction rate may be related to the decrease of HERG protein expression in ICC in gallbladder bottom tissue.

Biosynthesis regulation and drug development for human ether-a-go-go related gene potassium channel: Research advances / 国际药学研究杂志

Human ether-a-go-go related gene(hERG) encodes a subunit of Ikr potassium channel which plays an essential role n IH phase repolarization of action potential. The expression and/or function of hERG channel could be nfluenced by mang factors, such as diverse drugs,low temperature or low K+,which may cause the QT nterval prolongation, torsade de points and even sudden cardiac death. Therefore, the research of hERG potassium channel has significance for guiding development of new drugs and ndividualized treatment of arrhythmia. The hERG potassium channels as anti-arrhythmic drug treatment target which plays an mportant roles in new drugs safety test and development. This review summarizes recent progresses of structure and functions of hERG channel, the biosynthesis process of hERG potassium channel and regulatory elements, relationship between hERG potassium channel and ong QT syndrome, and treatment for abnormal expression of hERG channel, which provides reference and basis for in-depth study of hERG channel.

Electrophysiological Study of V535M hERG Mutation of LQT2 / 华中科技大学学报（医学）（英德文版）

This study examined the current changes of human ether-a-go-go-related gene (hERG) mutation derived from a LQT2 Chinese family with a highly penetrating phenotype.Mutation was identified and site-directed mutagenesis was performed to induce the mutation in wild-type (WT) hERG.WT　hERG and mutated V535M were cloned and transiently expressed in HEK293 cells.At the 48th and 72nd h after transfection,membrane currents were recorded using whole cell patch-clamp procedures.An A＞G transition at 1605 resulting in replacement of V535M was identified.Compared to WT,V535M mutation significantly decreased tail currents of hERG.At test potential of-40 mV after depolarizing at +50 mV,tail current densities were 83.35±7.06 pA/pF in WT and 50.38±7.74 pA/pF in V535M respectively (n=20,P＜0.01).Gating kinetics of hERG revealed that V1/2 of steady-state inactivation shifted to negative potential in the mutant (V1/2,V535M:-61.81±1.7 mV vs.V1/2,WT:-43.1±0.71mV).The time constant of recovery from inactivation was markedly prolonged in the mutant compared to WT among test potentials.V535M hERG mutation demonstrated markedly decreased tail current densities,which suggests that V535M is a new loss-of-function mutation of bERG channel responsible for LQT2.

A novel mutation-L539fs/47 of hERG in a Chinese long QT syndrome family / 药物分析学报

Objective To identify the mutation of human ether-a-go-go-related gene (hERG) and analyze the clinical characteristics of a Chinese family with long ST syndrome (LQTS). Methods The electrocardiogram and DNA samples were obtained from a Chinese LQTS family of 26 members. Genotype was performed with polymorphic short tandem repeat (STR) markers at the known LQT1, LQT2, and LQT3 loci. SSCP analysis was used to find aberrant conformers. hERG mutation was confirmed by cloning and sequencing. Results Three gene carriers were linked to chromosome 7q35-36, where the potassium channel gene hERG was encoded. A 19-base pair deletion was identified. The mutation was located at nucleotide position 1 619-1 637 between transmembrane domains S4 and S5. Furthermore, A1692G polymorphism was found both in the normal control and patients. Conclusion A novel 19 bp deletion mutation of hERG is identified in a Chinese family. All gene carriers are demonstrated to be typical LQT2 ECG phenotype.

A novel mutation - L539fs/47 of hERG in a Chinese long QT syndrome family / 西安交通大学学报·英文版

Objective: To identify the mutation of human ether-a-go-go-related gene (hERG) and analyze the clinical characteristics of a Chinese family with long ST syndrome (LQTS). Methods: The electrocardiogram and DNA samples were obtained from a Chinese LQTS family of 26 members. Genotype was performed with polymorphic short tandem repeat (STR) markers at the known LQT1, LQT2, and LQT3 loci. SSCP analysis was used to find aberrant conformers. hERG mutation was confirmed by cloning and sequencing. Results: Three gene carriers were linked to chromosome 7q35-36, where the potassium channel gene hERG was encoded. A 19-base pair deletion was identified. The mutation was located at nucleotide position 1619-1637 between transmembrane domains S4 and S5. Furthermore, A1692G polymorphism was found both in the normal control and patients. Conclusion: A novel 19 bp deletion mutation of hERG is identified in a Chinese family. All gene carriers are demonstrated to be typical LQT2 ECG phenotype.