The human RNA methyltransferase like i gene (RNMTL1) is one of thirteen newly discovered geneswithin a 116 Kb segment of the chromosome 17p13.3 that suffers from a high frequent loss of heterozygosityin human hepatoce...The human RNA methyltransferase like i gene (RNMTL1) is one of thirteen newly discovered geneswithin a 116 Kb segment of the chromosome 17p13.3 that suffers from a high frequent loss of heterozygosityin human hepatocellular carcinoma in China[1-5]. To understand the molecular mechanisms underlyingtranscription control of the RNMTL1 gene in human cancers, we decline using of the conventional approachwhere the cis-elements bound by the known transcription factors are primary targets, and carried out thesystematic analyses to dissect the promoter structure and identify/characterize the key cis-elements thatare responsible for its strong expression in cell. The molecular approaches applied included 1, the primerextension for mapping of the transcription starts; 2, the transient transfection/reporter assays on a largenumber of deletion and site-specific mutants of the promoter segment for defining the minimal promoterand the crucial elements within; and 3, the electrophoresis mobility shift assay with specific antibodies forreconfirming the nature of the transcription factors and their cognate cis-elements. We have shown that theinteraction of an ATF/CREB element (-38 to -31) and its cognate transcription factors play a predominantrole in the promoter activity of the RNMTL1 gene. The secondary DNA structures of the ATF/CREBelement play a more vital role in the protein-DNA interaction. Finally, we reported a novel mechanismunderlying the YY1 mediated transcription repression, namely, the ATF/CREB dependent transcription-repression by YY1 is executed in absence of its own sequence-specific binding.展开更多
Using a combination of hybridization of PAC to a cDNA library and RACE technique, we isolated a novel cDNA, designated as C17orf25 (Chromosome 17 open rea(ling frame 25, previously named it HC71A), from the deletion r...Using a combination of hybridization of PAC to a cDNA library and RACE technique, we isolated a novel cDNA, designated as C17orf25 (Chromosome 17 open rea(ling frame 25, previously named it HC71A), from the deletion region on chromosome 17p13.3. The cDNA encodes a protein of 313 amino acids with a calculated molecular mass of 34.8 kDa. C17orf25 is divided into 10 exons and 9 introns, spanning 23 kb of genomic DNA. Northern blot analysis showed that the mRNA expression of C17orf25 was decreased in hepatocellular carcinoma samples as compared to adjacent noncancerous liver tissues from the same patients. The transfection of C17or25 into the hepatocellular carcinoma cell SMMC7721 and overexpression could inhibit the cell growth. The above results indicate that C17orf25 is a novel human gene, and the cloning and preliminary characterization of C17orf25 is a prerequisite for further functional analysis of this novel gene in human hepatocellular carcinoma.展开更多
The human RNA methyltransferase like 1 gene (RNMTL1) is one of thirteen newly discovered genes within a 116 Kb segment of the chromosome 17pl3.3 that suffers from a high frequent loss of heterozygosity in human hepato...The human RNA methyltransferase like 1 gene (RNMTL1) is one of thirteen newly discovered genes within a 116 Kb segment of the chromosome 17pl3.3 that suffers from a high frequent loss of heterozygosity in human hepatocellular carcinoma in China[1-5]. To understand the molecular mechanisms underlying transcription control of the RNMTL1 gene in human cancers, we decline using of the conventional approach where the cis-elements bound by the known transcription factors are primary targets, and carried out the systematic analyses to dissect the promoter structure and identify/characterize the key cis-elements that are responsible for its strong expression in cell. The molecular approaches applied included 1, the primer extension for mapping of the transcription starts; 2, the transient transfection/reporter assays on a large number of deletion and site-specific mutants of the promoter segment for defining the minimal promoter and the crucial elements within; and 3, the electrophoresis mobility shift assay with specific antibodies for reconfirming the nature of the transcription factors and their cognate cis-elements. We have shown that the interaction of an ATF/CREB element (-38 to -31) and its cognate transcription factors play a predominant role in the promoter activity of the RNMTL1 gene. The secondary DNA structures of the ATF/CREB element play a more vital role in the protein-DNA interaction. Finally, we reported a novel mechanism underlying the YY1 mediated transcription repression, namely, the ATF/CREB dependent transcription-repression by YY1 is executed in absence of its own sequence-specific binding.展开更多
Objective:Genome-wide association studies(GWAS)have identified over 150 risk loci linked to colorectal cancer(CRC),including the 17p13.3 locus with the tag single nucleotide polymorphism(SNP)rs12603526 in the Asian po...Objective:Genome-wide association studies(GWAS)have identified over 150 risk loci linked to colorectal cancer(CRC),including the 17p13.3 locus with the tag single nucleotide polymorphism(SNP)rs12603526 in the Asian population.However,the specific causal gene and the functional regulatory mechanisms in this region remain unresolved,necessitating further investigation to elucidate the underlying mechanisms of CRC.Methods:We employed an RNA interference-based functional approach to identify genes critical for CRC cell proliferation at the GWAS locus 17p13.3.Bioinformatic fine-mapping analysis was conducted to prioritize causal variants.A large-scale study involving 7,013 cases and 7,329 controls from a Chinese population,along with another cohort of 5,158 cases and 20,632 controls from the UK Biobank,was performed to validate the association between the candidate variant and the gene.A series of biological experiments was conducted to explore the function of the candidate gene and its regulatory mechanisms.Results:We identified FAM57A as a key oncogene that promotes CRC cell proliferation,and confirmed its carcinogenic role through in vitro proliferation assays.The variant rs526835 was prioritized as a causal candidate for CRC risk,located in a functional region with enhancer properties,and showed a significant quantitative association with FAM57A expression.The rs526835[T]variant was associated with a 1.17-fold increase in CRC risk[95%confidence interval(95%CI):1.11−1.23,P=1.23×10−9]in the large-scale Chinese cohort,which was further corroborated in the UK Biobank cohort.Mechanistically,we demonstrated that rs526835 enhances a promoterenhancer interaction mediated by the transcription factor JUN,leading to increased expression of FAM57A.Conclusions:We reveal the underlying mechanisms of CRC predisposition at the GWAS locus 17p13.3.Additionally,our findings highlight the critical role of FAM57A in CRC pathogenesis and introduce a novel enhancer-promoter interaction between FAM57A and rs526835,which could inform future precision prevention and personalized cancer therapies.展开更多
目的探讨17 p 13.3微缺失综合征的临床表型、拷贝数变异、治疗及预后。方法回顾性分析5例17p13.3微缺失综合征患儿临床资料、全外显子组测序结果以及治疗效果。结果5例患儿均表现为身材矮小,例3~5合并有心血管异常。全外显子组测序提示...目的探讨17 p 13.3微缺失综合征的临床表型、拷贝数变异、治疗及预后。方法回顾性分析5例17p13.3微缺失综合征患儿临床资料、全外显子组测序结果以及治疗效果。结果5例患儿均表现为身材矮小,例3~5合并有心血管异常。全外显子组测序提示所有的患儿均存在17p13.3染色体片段缺失,缺失大小为433~1536 kb,主要包括YWHAE、CRK基因,但不包括PAFAH1B1基因。在排除了生长激素禁忌证后,4例接受了重组人生长激素治疗。矮小症患儿的身高在应用重组人生长激素治疗后初期得到改善,但后期治疗效果欠佳。2例满足手术指征而接受外科手术以纠正先天性心脏畸形。结论17p13.3染色体片段缺失可导致17p13.3微缺失综合征,通过全外显子组测序,可以提高对于存在先天性心脏畸形和/或矮小症的儿童的诊断率,及时采取心血管及身高方面的治疗有助于改善患儿预后。展开更多
We report the case of a male patient with Miller-Dieker syndrome(MDS)and gallbladder cancer.Chromosome analysis by fluorescence in situ hybridization revealed a deletion in the 17p13.3 region,an area thought to contai...We report the case of a male patient with Miller-Dieker syndrome(MDS)and gallbladder cancer.Chromosome analysis by fluorescence in situ hybridization revealed a deletion in the 17p13.3 region,an area thought to contain tumour suppressor genes,including the hypermethylated in cancer 1 gene.Considering the rarity of gallbladder cancer in children,we propose that MDS as the genetic background of this patient may have played a role in the occurrence of gallbladder cancer.Conclusion:Our present report indicates that the emergence of cancers should be taken into consideration during the long-term follow-up of patients with MDS.展开更多
文摘The human RNA methyltransferase like i gene (RNMTL1) is one of thirteen newly discovered geneswithin a 116 Kb segment of the chromosome 17p13.3 that suffers from a high frequent loss of heterozygosityin human hepatocellular carcinoma in China[1-5]. To understand the molecular mechanisms underlyingtranscription control of the RNMTL1 gene in human cancers, we decline using of the conventional approachwhere the cis-elements bound by the known transcription factors are primary targets, and carried out thesystematic analyses to dissect the promoter structure and identify/characterize the key cis-elements thatare responsible for its strong expression in cell. The molecular approaches applied included 1, the primerextension for mapping of the transcription starts; 2, the transient transfection/reporter assays on a largenumber of deletion and site-specific mutants of the promoter segment for defining the minimal promoterand the crucial elements within; and 3, the electrophoresis mobility shift assay with specific antibodies forreconfirming the nature of the transcription factors and their cognate cis-elements. We have shown that theinteraction of an ATF/CREB element (-38 to -31) and its cognate transcription factors play a predominantrole in the promoter activity of the RNMTL1 gene. The secondary DNA structures of the ATF/CREBelement play a more vital role in the protein-DNA interaction. Finally, we reported a novel mechanismunderlying the YY1 mediated transcription repression, namely, the ATF/CREB dependent transcription-repression by YY1 is executed in absence of its own sequence-specific binding.
基金the National 863High Technology Research and Development Pro-gram of China (Zl9-02--0l-0l) to Wan DF and theProject of Ch
文摘Using a combination of hybridization of PAC to a cDNA library and RACE technique, we isolated a novel cDNA, designated as C17orf25 (Chromosome 17 open rea(ling frame 25, previously named it HC71A), from the deletion region on chromosome 17p13.3. The cDNA encodes a protein of 313 amino acids with a calculated molecular mass of 34.8 kDa. C17orf25 is divided into 10 exons and 9 introns, spanning 23 kb of genomic DNA. Northern blot analysis showed that the mRNA expression of C17orf25 was decreased in hepatocellular carcinoma samples as compared to adjacent noncancerous liver tissues from the same patients. The transfection of C17or25 into the hepatocellular carcinoma cell SMMC7721 and overexpression could inhibit the cell growth. The above results indicate that C17orf25 is a novel human gene, and the cloning and preliminary characterization of C17orf25 is a prerequisite for further functional analysis of this novel gene in human hepatocellular carcinoma.
基金This work is supported by the 973 projects of China (G1998051004) to Jingde Zhu and (G199805l200) to Dafang Wan, respectively.Thanks are due to Hongyu Zhang and other mem-bers in Jingde Zhu's lab for assistance and helps onnumerous occasions.
文摘The human RNA methyltransferase like 1 gene (RNMTL1) is one of thirteen newly discovered genes within a 116 Kb segment of the chromosome 17pl3.3 that suffers from a high frequent loss of heterozygosity in human hepatocellular carcinoma in China[1-5]. To understand the molecular mechanisms underlying transcription control of the RNMTL1 gene in human cancers, we decline using of the conventional approach where the cis-elements bound by the known transcription factors are primary targets, and carried out the systematic analyses to dissect the promoter structure and identify/characterize the key cis-elements that are responsible for its strong expression in cell. The molecular approaches applied included 1, the primer extension for mapping of the transcription starts; 2, the transient transfection/reporter assays on a large number of deletion and site-specific mutants of the promoter segment for defining the minimal promoter and the crucial elements within; and 3, the electrophoresis mobility shift assay with specific antibodies for reconfirming the nature of the transcription factors and their cognate cis-elements. We have shown that the interaction of an ATF/CREB element (-38 to -31) and its cognate transcription factors play a predominant role in the promoter activity of the RNMTL1 gene. The secondary DNA structures of the ATF/CREB element play a more vital role in the protein-DNA interaction. Finally, we reported a novel mechanism underlying the YY1 mediated transcription repression, namely, the ATF/CREB dependent transcription-repression by YY1 is executed in absence of its own sequence-specific binding.
基金supported by the Program of National Science Fund for Distinguished Young Scholars of China(No.81925032)Key Program of National Natural Science Foundation of China(No.82130098)National Natural Science Foundation of China(No.82304232)。
文摘Objective:Genome-wide association studies(GWAS)have identified over 150 risk loci linked to colorectal cancer(CRC),including the 17p13.3 locus with the tag single nucleotide polymorphism(SNP)rs12603526 in the Asian population.However,the specific causal gene and the functional regulatory mechanisms in this region remain unresolved,necessitating further investigation to elucidate the underlying mechanisms of CRC.Methods:We employed an RNA interference-based functional approach to identify genes critical for CRC cell proliferation at the GWAS locus 17p13.3.Bioinformatic fine-mapping analysis was conducted to prioritize causal variants.A large-scale study involving 7,013 cases and 7,329 controls from a Chinese population,along with another cohort of 5,158 cases and 20,632 controls from the UK Biobank,was performed to validate the association between the candidate variant and the gene.A series of biological experiments was conducted to explore the function of the candidate gene and its regulatory mechanisms.Results:We identified FAM57A as a key oncogene that promotes CRC cell proliferation,and confirmed its carcinogenic role through in vitro proliferation assays.The variant rs526835 was prioritized as a causal candidate for CRC risk,located in a functional region with enhancer properties,and showed a significant quantitative association with FAM57A expression.The rs526835[T]variant was associated with a 1.17-fold increase in CRC risk[95%confidence interval(95%CI):1.11−1.23,P=1.23×10−9]in the large-scale Chinese cohort,which was further corroborated in the UK Biobank cohort.Mechanistically,we demonstrated that rs526835 enhances a promoterenhancer interaction mediated by the transcription factor JUN,leading to increased expression of FAM57A.Conclusions:We reveal the underlying mechanisms of CRC predisposition at the GWAS locus 17p13.3.Additionally,our findings highlight the critical role of FAM57A in CRC pathogenesis and introduce a novel enhancer-promoter interaction between FAM57A and rs526835,which could inform future precision prevention and personalized cancer therapies.
文摘目的探讨17 p 13.3微缺失综合征的临床表型、拷贝数变异、治疗及预后。方法回顾性分析5例17p13.3微缺失综合征患儿临床资料、全外显子组测序结果以及治疗效果。结果5例患儿均表现为身材矮小,例3~5合并有心血管异常。全外显子组测序提示所有的患儿均存在17p13.3染色体片段缺失,缺失大小为433~1536 kb,主要包括YWHAE、CRK基因,但不包括PAFAH1B1基因。在排除了生长激素禁忌证后,4例接受了重组人生长激素治疗。矮小症患儿的身高在应用重组人生长激素治疗后初期得到改善,但后期治疗效果欠佳。2例满足手术指征而接受外科手术以纠正先天性心脏畸形。结论17p13.3染色体片段缺失可导致17p13.3微缺失综合征,通过全外显子组测序,可以提高对于存在先天性心脏畸形和/或矮小症的儿童的诊断率,及时采取心血管及身高方面的治疗有助于改善患儿预后。
文摘We report the case of a male patient with Miller-Dieker syndrome(MDS)and gallbladder cancer.Chromosome analysis by fluorescence in situ hybridization revealed a deletion in the 17p13.3 region,an area thought to contain tumour suppressor genes,including the hypermethylated in cancer 1 gene.Considering the rarity of gallbladder cancer in children,we propose that MDS as the genetic background of this patient may have played a role in the occurrence of gallbladder cancer.Conclusion:Our present report indicates that the emergence of cancers should be taken into consideration during the long-term follow-up of patients with MDS.
