Gap junctional intercellular communicationexchange of small molecules and ions between contiguous cells through membranous gap junctional channelsis essential for growth control and tissue homecotasis. This work conce...Gap junctional intercellular communicationexchange of small molecules and ions between contiguous cells through membranous gap junctional channelsis essential for growth control and tissue homecotasis. This work concerns the functional expression of gap junction protein connexin 43 (Cx43) in normal human lung cells and the changes in lung carcinoma cells. By. using Northern blot hybridization analysis and Cx43 immunocytochemical methods, it was otherved that cultured normal human embryonic lung cells expressed a high level of Cx43 in both mRNA and protein levels.The Cx43 immunofluorescence was localized at cell membrane regions corresponding to the location of gap junctions. These normal lung cells were competent of intercellular communication function as detected by Lucifer yellow dye transfer. In contrast to normal celis, Cx43 mRNA and protein was not detectable in the carcinoma PG cell line. These tumor cells were defective of intercellular communication function. These results demonstrate that Cx43 is expressed in normal cultured human embryonic lung cells but not in lung tumor cells. The lack of intercellular communication in the lung tumor cell line correlates with dysfunctional intercellular communication. The suggestive role of Cx as a tumor suppersor gene is discussed.展开更多
Background： Among patients with Charcot-Marie-Tooth disease （CMT）, the X-linked variant （CMTX） caused by gap junction protein beta 1 （GJB1） gene mutation is the second most frequent type, accounting for approxi...Background： Among patients with Charcot-Marie-Tooth disease （CMT）, the X-linked variant （CMTX） caused by gap junction protein beta 1 （GJB1） gene mutation is the second most frequent type, accounting for approximately 90% of all CMTX. More than 400 mutations have been identified in the GJB1 gene that encodes connexin 32 （CX32）. CX32 is thought to form gap junctions that promote the diffusion pathway between cells. GJB1 mutations interfere with the formation of the functional channel and impair the maintenance of peripheral myelin, and novel mutations are continually discovered. Methods： We included 79 unrelated patients clinically diagnosed with CMT at the Department of Neurology of the Chinese People＇s Liberation Army General Hospital from December 20, 2012, to December 31, 2015. Clinical examination, nerve conduction studies, and molecular and bioinformatics analyses were performed to identify patients with CMTX 1. Results： Nine GJBI mutations （c.283G〉A, c.77C〉T, c.643C〉T, c.515C〉T, c.191G〉A, c.610C〉T, c.490C〉T, c.491G〉A, and c.44G〉A） were discovered in nine patients. Median motor nerve conduction velocities of all nine patients were 〈 38 m/s, resembling CMT Type 1. Three novel mutations, c.643C〉T, c.191G〉A, and c.610C〉T, were revealed and bioinformatics analyses indicated high pathogenicity. Conclusions： The three novel missense mutations within the GJB1 gene broaden the mutational diversity ofCMT1X. Molecular analysis of family members and bioinformatics analyses of the afflicted patients confirmed the pathogenicity of these mutations.展开更多
By homologous EST searching and nested PCR a new human gene GJB5 encoding gap junction protein p-5 was identified. GJB5 was genetically mapped to human chromosome 1p33-p35 by FISH. RT-PCR revealed that it was expresse...By homologous EST searching and nested PCR a new human gene GJB5 encoding gap junction protein p-5 was identified. GJB5 was genetically mapped to human chromosome 1p33-p35 by FISH. RT-PCR revealed that it was expressed in skin, placenta and fetal skin. DMA sequencing of GJB5 was carried out in 142 patients with sensorineural hearing impairment and probands of 36 families with genetic diseases, including erythrokeratodermia (5 families), Char-cot-Marie-Tooth disease (13), ptosis (4), and retinitis pigmentosa and deafness (14). Two mis-sense mutations (686A→G, H229R; 25C→T, L9F) were detected in two sensorineural hearing impairment families. A heterologous deletion of 18 bp within intron was found in 3 families with heredity hearing impairment, and in one of the 3 families, a missense mutation (R265P) was identified also. But the deletion and missense mutation seemed not segregating with hearing impairment in the family. No abnormal mRNA or mRNA expression was detected in deletion carriers by RT-PCR analysis in skin tissue. Mutation analysis in 199 unaffected individuals revealed that two of them were carriers with the same 18 bp deletion.展开更多
目的探讨体外培养豚鼠膀胱组织ICCs细胞(interstitial cells of Cajal,ICCs)间隙连接蛋白Connexin43的表达。方法胶原酶消化法进行豚鼠膀胱组织ICCs细胞的原代培养,对照为原代培养膀胱平滑肌细胞,免疫荧光法进行两种细胞的特征性蛋白c-...目的探讨体外培养豚鼠膀胱组织ICCs细胞(interstitial cells of Cajal,ICCs)间隙连接蛋白Connexin43的表达。方法胶原酶消化法进行豚鼠膀胱组织ICCs细胞的原代培养,对照为原代培养膀胱平滑肌细胞,免疫荧光法进行两种细胞的特征性蛋白c-kit及平滑肌肌动蛋白(smooth muscle actin,SMA)染色观察,免疫荧光法及Western blot法进行培养细胞Connexin43的检测。结果豚鼠膀胱ICCs细胞特征性蛋白c-kit染色阳性,SMA染色阴性。豚鼠膀胱ICCs细胞间隙连接蛋白Connexin43表达水平较高,显著高于膀胱平滑肌细胞。结论豚鼠离体膀胱ICCs细胞间隙连接蛋白Connexin43高表达可能是其信号传递的重要物质基础。展开更多
目的分析内蒙古地区23个非综合征型耳聋家系缝隙连接蛋白β2(gap junction protein beta 2,GJB2)基因突变特点,探讨该耳聋家系遗传学病因。方法对内蒙古地区23个非综合征型遗传性聋家系共122人进行问卷调查、听力学检查,提取外周血DNA,...目的分析内蒙古地区23个非综合征型耳聋家系缝隙连接蛋白β2(gap junction protein beta 2,GJB2)基因突变特点,探讨该耳聋家系遗传学病因。方法对内蒙古地区23个非综合征型遗传性聋家系共122人进行问卷调查、听力学检查,提取外周血DNA,经聚合酶链反应(PCR)扩增GJB2基因编码区进行直接测序,运用DNAStar软件进行测序结果分析。结果共检测到8个家系46名家系个体存在8种GJB2基因核酸序列改变。包括5种致病突变及3种多态性改变,明确了6个耳聋家系的遗传学病因为GJB2基因纯合突变所致。GJB2基因突变在23个家系中的检出率为33%(8/23),在122个家系个体的检出率为33%(37/122),在62例耳聋患者中的检出率为60%(37/62)。c.235delC突变检出率最高,为52%(32/62),其次为c.299-300delAT,突变携带率为8%(5/62)。结论内蒙古地区家系遗传性聋GJB2基因突变有较高的携带率,c.235delC位点是最常见的致病位点,其次为c.299-300delAT。以散发耳聋患者为根源,对其亲属进行耳聋基因筛查可以更加高效的发现潜在的耳聋基因突变携带者。展开更多
目的:探讨缝隙连接蛋白beta2(GJB2)基因rs2274083、rs2274084和rs72474224位点多态性与汉族人群职业噪声性听力损失易感性之间的关系。方法:应用1∶1病例-对照研究,病例组177例为电测听结果双耳高频平均听阈≥40 d B的在岗工人,对照组17...目的:探讨缝隙连接蛋白beta2(GJB2)基因rs2274083、rs2274084和rs72474224位点多态性与汉族人群职业噪声性听力损失易感性之间的关系。方法:应用1∶1病例-对照研究,病例组177例为电测听结果双耳高频平均听阈≥40 d B的在岗工人,对照组177例为年龄、性别、作业工龄与病例组相匹配,并且电测听结果双耳高频平均听阈<25 d B的同岗位轮班工人。采用PCR扩增177对样本目的基因片段,对目的基因片段进行测序,确定待研究位点的基因型。结果:GJB2基因的rs2274084位点C、T等位基因频率在病例组和对照组中分布分别为73.73%、26.27%和63.84%、36.16%,其中CC、TC、TT基因型在病例组和对照组中的分布分别为55.37%、36.72%、7.91%和40.11%、47.46%、12.43%。该位点的基因型频率与等位基因频率在病例与对照组之间的差异均具有统计学意义(P<0.05)。rs2274083和rs72474224位点基因型分布在病例与对照组间的差异均无统计学意义(P>0.05)。结论:GJB2rs2274084可能是汉族人群职业噪声性听力损失的易感基因位点,携带C等位基因的工人,暴露职业噪声时更易发生听力损失。展开更多
文摘Gap junctional intercellular communicationexchange of small molecules and ions between contiguous cells through membranous gap junctional channelsis essential for growth control and tissue homecotasis. This work concerns the functional expression of gap junction protein connexin 43 (Cx43) in normal human lung cells and the changes in lung carcinoma cells. By. using Northern blot hybridization analysis and Cx43 immunocytochemical methods, it was otherved that cultured normal human embryonic lung cells expressed a high level of Cx43 in both mRNA and protein levels.The Cx43 immunofluorescence was localized at cell membrane regions corresponding to the location of gap junctions. These normal lung cells were competent of intercellular communication function as detected by Lucifer yellow dye transfer. In contrast to normal celis, Cx43 mRNA and protein was not detectable in the carcinoma PG cell line. These tumor cells were defective of intercellular communication function. These results demonstrate that Cx43 is expressed in normal cultured human embryonic lung cells but not in lung tumor cells. The lack of intercellular communication in the lung tumor cell line correlates with dysfunctional intercellular communication. The suggestive role of Cx as a tumor suppersor gene is discussed.
文摘Background： Among patients with Charcot-Marie-Tooth disease （CMT）, the X-linked variant （CMTX） caused by gap junction protein beta 1 （GJB1） gene mutation is the second most frequent type, accounting for approximately 90% of all CMTX. More than 400 mutations have been identified in the GJB1 gene that encodes connexin 32 （CX32）. CX32 is thought to form gap junctions that promote the diffusion pathway between cells. GJB1 mutations interfere with the formation of the functional channel and impair the maintenance of peripheral myelin, and novel mutations are continually discovered. Methods： We included 79 unrelated patients clinically diagnosed with CMT at the Department of Neurology of the Chinese People＇s Liberation Army General Hospital from December 20, 2012, to December 31, 2015. Clinical examination, nerve conduction studies, and molecular and bioinformatics analyses were performed to identify patients with CMTX 1. Results： Nine GJBI mutations （c.283G〉A, c.77C〉T, c.643C〉T, c.515C〉T, c.191G〉A, c.610C〉T, c.490C〉T, c.491G〉A, and c.44G〉A） were discovered in nine patients. Median motor nerve conduction velocities of all nine patients were 〈 38 m/s, resembling CMT Type 1. Three novel mutations, c.643C〉T, c.191G〉A, and c.610C〉T, were revealed and bioinformatics analyses indicated high pathogenicity. Conclusions： The three novel missense mutations within the GJB1 gene broaden the mutational diversity ofCMT1X. Molecular analysis of family members and bioinformatics analyses of the afflicted patients confirmed the pathogenicity of these mutations.
文摘By homologous EST searching and nested PCR a new human gene GJB5 encoding gap junction protein p-5 was identified. GJB5 was genetically mapped to human chromosome 1p33-p35 by FISH. RT-PCR revealed that it was expressed in skin, placenta and fetal skin. DMA sequencing of GJB5 was carried out in 142 patients with sensorineural hearing impairment and probands of 36 families with genetic diseases, including erythrokeratodermia (5 families), Char-cot-Marie-Tooth disease (13), ptosis (4), and retinitis pigmentosa and deafness (14). Two mis-sense mutations (686A→G, H229R; 25C→T, L9F) were detected in two sensorineural hearing impairment families. A heterologous deletion of 18 bp within intron was found in 3 families with heredity hearing impairment, and in one of the 3 families, a missense mutation (R265P) was identified also. But the deletion and missense mutation seemed not segregating with hearing impairment in the family. No abnormal mRNA or mRNA expression was detected in deletion carriers by RT-PCR analysis in skin tissue. Mutation analysis in 199 unaffected individuals revealed that two of them were carriers with the same 18 bp deletion.
文摘目的分析内蒙古地区23个非综合征型耳聋家系缝隙连接蛋白β2(gap junction protein beta 2,GJB2)基因突变特点,探讨该耳聋家系遗传学病因。方法对内蒙古地区23个非综合征型遗传性聋家系共122人进行问卷调查、听力学检查,提取外周血DNA,经聚合酶链反应(PCR)扩增GJB2基因编码区进行直接测序,运用DNAStar软件进行测序结果分析。结果共检测到8个家系46名家系个体存在8种GJB2基因核酸序列改变。包括5种致病突变及3种多态性改变,明确了6个耳聋家系的遗传学病因为GJB2基因纯合突变所致。GJB2基因突变在23个家系中的检出率为33%(8/23),在122个家系个体的检出率为33%(37/122),在62例耳聋患者中的检出率为60%(37/62)。c.235delC突变检出率最高,为52%(32/62),其次为c.299-300delAT,突变携带率为8%(5/62)。结论内蒙古地区家系遗传性聋GJB2基因突变有较高的携带率,c.235delC位点是最常见的致病位点,其次为c.299-300delAT。以散发耳聋患者为根源,对其亲属进行耳聋基因筛查可以更加高效的发现潜在的耳聋基因突变携带者。
文摘目的:探讨缝隙连接蛋白beta2(GJB2)基因rs2274083、rs2274084和rs72474224位点多态性与汉族人群职业噪声性听力损失易感性之间的关系。方法:应用1∶1病例-对照研究,病例组177例为电测听结果双耳高频平均听阈≥40 d B的在岗工人,对照组177例为年龄、性别、作业工龄与病例组相匹配,并且电测听结果双耳高频平均听阈<25 d B的同岗位轮班工人。采用PCR扩增177对样本目的基因片段,对目的基因片段进行测序,确定待研究位点的基因型。结果:GJB2基因的rs2274084位点C、T等位基因频率在病例组和对照组中分布分别为73.73%、26.27%和63.84%、36.16%,其中CC、TC、TT基因型在病例组和对照组中的分布分别为55.37%、36.72%、7.91%和40.11%、47.46%、12.43%。该位点的基因型频率与等位基因频率在病例与对照组之间的差异均具有统计学意义(P<0.05)。rs2274083和rs72474224位点基因型分布在病例与对照组间的差异均无统计学意义(P>0.05)。结论:GJB2rs2274084可能是汉族人群职业噪声性听力损失的易感基因位点,携带C等位基因的工人,暴露职业噪声时更易发生听力损失。
