As an essential transcriptional activator,PDX1 plays a crucial role in pancreatic development andβ-cell function.Mutations in the PDX1 gene may lead to type 4 maturityonset diabetes of the young(MODY4)and neonatal di...As an essential transcriptional activator,PDX1 plays a crucial role in pancreatic development andβ-cell function.Mutations in the PDX1 gene may lead to type 4 maturityonset diabetes of the young(MODY4)and neonatal diabetes mellitus.However,the precise mechanisms underlying MODY4 remain elusive due to the paucity of clinical samples and pronounced differences in pancreatic architecture and genomic composition between humans and existing animal models.In this study,three PDX1-mutant cynomolgus macaques were generated using CRISPR/Cas9 technology,all of which succumbed shortly postpartum,exhibiting pancreatic agenesis.Notably,one tri-allelic PDX1-mutant cynomolgus macaque(designated as M4)developed a pancreas,whereas the two monoallelic PDX1-mutant cynomolgus macaques displayed no anatomical evidence of pancreatic formation.RNA sequencing of the M4 pancreas revealed substantial molecular changes in both endocrine and exocrine functions,indicating developmental delay and PDX1haploinsufficiency.A marked change in m6A methylation was identified in the M4 pancreas,confirmed through cultured PDX1-mutantisletorganoids.Notably,overexpression of the m6A modulator METTL3 restored function in heterozygous PDX1-mutant islet organoids.This study highlights a novel role of m6A methylation modification in the progression of MODY4 and provides valuable molecular insights for preclinical research.展开更多
BACKGROUND Aberrant expression of stanniocalcin 2 (STC2) is implicated in colon adenocarcinoma (COAD). A previous study identified that STC2 functions as a tumor promoter to drive development of some cancers, but the ...BACKGROUND Aberrant expression of stanniocalcin 2 (STC2) is implicated in colon adenocarcinoma (COAD). A previous study identified that STC2 functions as a tumor promoter to drive development of some cancers, but the role of its overexpression in the development of COAD remains unclear. AIM To evaluate the regulation mechanism of STC2 overexpression in COAD. METHODS The expression of STC2 in COAD was assessed by TCGA COAD database and GEO (GSE50760). Methylation level of the STC2 promoter was evaluated with beta value in UALCAN platform, and the correlation between STC2 expression and survival rate was investigated with TCGA COAD. Transcription binding site prediction was conducted by TRANSFAC and LASAGNA, and a luciferase reporter system was used to identify STC2 promoter activity in several cell lines, including HEK293T, NCM460, HT29, SW480, and HCT116. Western blotting was performed to evaluate the role of Sp1 on the expression of STC2. RESULTS The central finding of this work is that STC2 is overexpressed in COAD tissues and positively correlated with poor prognosis. Importantly, the binding site of the transcription factor Sp1 is widely located in the promoter region of STC2. A luciferase reporter system was successfully constructed to analyze the transcription activity of STC2, and knocking down the expression of Sp1 significantly inhibited the transcription activity of STC2. Furthermore, inhibition of Sp1 remarkably decreased protein levels of STC2. CONCLUSION Our data provide evidence that the transcription factor Sp1 is essential for the overexpression of STC2 in COAD through activation of promoter activity. Taken together, our finding provides new insights into the mechanism of oncogenic function of COAD by STC2.展开更多
基金supported by the National Key R&D Program of China(2018YFA0801404,2023YFC3403400)National Natural Science Foundation of China(81941006,32371190,32370878)+2 种基金Guangdong Special Support Program(2019BT02Y276,2024A1515012868)Double First-Class Discipline Promotion Project(2023B10564003)Program for Scientific Research Start-up Funds of Guangdong Ocean University(060302052408)。
文摘As an essential transcriptional activator,PDX1 plays a crucial role in pancreatic development andβ-cell function.Mutations in the PDX1 gene may lead to type 4 maturityonset diabetes of the young(MODY4)and neonatal diabetes mellitus.However,the precise mechanisms underlying MODY4 remain elusive due to the paucity of clinical samples and pronounced differences in pancreatic architecture and genomic composition between humans and existing animal models.In this study,three PDX1-mutant cynomolgus macaques were generated using CRISPR/Cas9 technology,all of which succumbed shortly postpartum,exhibiting pancreatic agenesis.Notably,one tri-allelic PDX1-mutant cynomolgus macaque(designated as M4)developed a pancreas,whereas the two monoallelic PDX1-mutant cynomolgus macaques displayed no anatomical evidence of pancreatic formation.RNA sequencing of the M4 pancreas revealed substantial molecular changes in both endocrine and exocrine functions,indicating developmental delay and PDX1haploinsufficiency.A marked change in m6A methylation was identified in the M4 pancreas,confirmed through cultured PDX1-mutantisletorganoids.Notably,overexpression of the m6A modulator METTL3 restored function in heterozygous PDX1-mutant islet organoids.This study highlights a novel role of m6A methylation modification in the progression of MODY4 and provides valuable molecular insights for preclinical research.
基金the Natural Science Foundation of Liaoning Province,China,No.20180550769
文摘BACKGROUND Aberrant expression of stanniocalcin 2 (STC2) is implicated in colon adenocarcinoma (COAD). A previous study identified that STC2 functions as a tumor promoter to drive development of some cancers, but the role of its overexpression in the development of COAD remains unclear. AIM To evaluate the regulation mechanism of STC2 overexpression in COAD. METHODS The expression of STC2 in COAD was assessed by TCGA COAD database and GEO (GSE50760). Methylation level of the STC2 promoter was evaluated with beta value in UALCAN platform, and the correlation between STC2 expression and survival rate was investigated with TCGA COAD. Transcription binding site prediction was conducted by TRANSFAC and LASAGNA, and a luciferase reporter system was used to identify STC2 promoter activity in several cell lines, including HEK293T, NCM460, HT29, SW480, and HCT116. Western blotting was performed to evaluate the role of Sp1 on the expression of STC2. RESULTS The central finding of this work is that STC2 is overexpressed in COAD tissues and positively correlated with poor prognosis. Importantly, the binding site of the transcription factor Sp1 is widely located in the promoter region of STC2. A luciferase reporter system was successfully constructed to analyze the transcription activity of STC2, and knocking down the expression of Sp1 significantly inhibited the transcription activity of STC2. Furthermore, inhibition of Sp1 remarkably decreased protein levels of STC2. CONCLUSION Our data provide evidence that the transcription factor Sp1 is essential for the overexpression of STC2 in COAD through activation of promoter activity. Taken together, our finding provides new insights into the mechanism of oncogenic function of COAD by STC2.
