Project description:Safeguarding replication fork stability in transcriptionally active regions, which require high DNA replication accuracy, is crucial for precise DNA replication and prevention of mutations. However, how cells ensure the stability of replication forks in these regions remains a critical challenge. Here, we discovered the pervasive existence of replication forks-associated RNA-DNA hybrids (RF-RDs) within transcriptionally active regions, where they act as a protective barrier against DNA2-mediated nascent DNA degradation and prevent replication fork collapse upon replication stress. Subsequently, the RNA helicase DDX39A dismantles RF-RDs, facilitating proper DNA2-mediated DNA resection and replication fork restart. Excessive dissolution of RF-RDs causes replication fork collapse and genomic instability, while insufficient dissolution of RF-RDs under replication stress increases fork stability, resulting in chemoresistance that can be reversed by eliminating RF-RDs. In summary, we elucidated the prevalence of RF-RDs at replication forks within transcriptionally active regions, revealed their pivotal role in safeguarding replication fork stability, and proposed that targeting RF-RDs holds promise for augmenting chemotherapeutic efficacy.
Project description:Safeguarding replication fork stability in transcriptionally active regions, which require high DNA replication accuracy, is crucial for precise DNA replication and prevention of mutations. However, how cells ensure the stability of replication forks in these regions remains a critical challenge. Here, we discovered the pervasive existence of replication forks-associated RNA-DNA hybrids (RF-RDs) within transcriptionally active regions, where they act as a protective barrier against DNA2-mediated nascent DNA degradation and prevent replication fork collapse upon replication stress. Subsequently, the RNA helicase DDX39A dismantles RF-RDs, facilitating proper DNA2-mediated DNA resection and replication fork restart. Excessive dissolution of RF-RDs causes replication fork collapse and genomic instability, while insufficient dissolution of RF-RDs under replication stress increases fork stability, resulting in chemoresistance that can be reversed by eliminating RF-RDs. In summary, we elucidated the prevalence of RF-RDs at replication forks within transcriptionally active regions, revealed their pivotal role in safeguarding replication fork stability, and proposed that targeting RF-RDs holds promise for augmenting chemotherapeutic efficacy.
Project description:Safeguarding replication fork stability in transcriptionally active regions, which require high DNA replication accuracy, is crucial for precise DNA replication and prevention of mutations. However, how cells ensure the stability of replication forks in these regions remains a critical challenge. Here, we discovered the pervasive existence of replication forks-associated RNA-DNA hybrids (RF-RDs) within transcriptionally active regions, where they act as a protective barrier against DNA2-mediated nascent DNA degradation and prevent replication fork collapse upon replication stress. Subsequently, the RNA helicase DDX39A dismantles RF-RDs, facilitating proper DNA2-mediated DNA resection and replication fork restart. Excessive dissolution of RF-RDs causes replication fork collapse and genomic instability, while insufficient dissolution of RF-RDs under replication stress increases fork stability, resulting in chemoresistance that can be reversed by eliminating RF-RDs. In summary, we elucidated the prevalence of RF-RDs at replication forks within transcriptionally active regions, revealed their pivotal role in safeguarding replication fork stability, and proposed that targeting RF-RDs holds promise for augmenting chemotherapeutic efficacy.
Project description:Neurodevelopmental disorders pose a severe health burden in our society, with remarkably increasing prevalence in children. Though radiofrequency radiation (RF) exposure to the prenatal brain is one of the environmental risks strongly associated with neurobehavioral disorders, its direct impact on human brain development remains largely unknown. Here we use human brain organoids representing the cortex, namely cortical organoids (hCOs) from human embryonic stem cells (hESC), to examine the effects of RF from mobile phones on corticogenesis. We found that RF exposure to brain organoids leads to structural impairment and the defective mitotic behaviors of radial glia progenitors, which carry out critical roles in neocortical expansion. We further uncovered that RF-treated organoids acquire the dysregulation in the transcriptional program, including the aberrant expression of autism risk genes and the morphologically and functionally abnormal neurons. Moreover, the RF shield made complete protection of the detrimental impact of RF on corticogenesis. Finally, we identified small molecule inhibitors for BET proteins that ameliorated RF-induced damages in cortical organoids. Our findings demonstrate how RF exposure impairs brain development and suggest new strategies to prevent RF-mediated brain damage.
Project description:Safeguarding replication fork stability in transcriptionally active regions, which require high DNA replication accuracy, is crucial for precise DNA replication and prevention of mutations. However, how cells ensure the stability of replication forks in these regions remains a critical challenge. Here, we discovered the pervasive existence of replication forks-associated RNA-DNA hybrids (RF-RDs) within transcriptionally active regions, where they act as a protective barrier against DNA2-mediated nascent DNA degradation and prevent replication fork collapse upon replication stress. Subsequently, the RNA helicase DDX39A dismantles RF-RDs, facilitating proper DNA2-mediated DNA resection and replication fork restart. Excessive dissolution of RF-RDs causes replication fork collapse and genomic instability, while insufficient dissolution of RF-RDs under replication stress increases fork stability, resulting in chemoresistance that can be reversed by eliminating RF-RDs. In summary, we elucidated the prevalence of RF-RDs at replication forks within transcriptionally active regions, revealed their pivotal role in safeguarding replication fork stability, and proposed that targeting RF-RDs holds promise for augmenting chemotherapeutic efficacy.
Project description:Safeguarding replication fork stability in transcriptionally active regions, which require high DNA replication accuracy, is crucial for precise DNA replication and prevention of mutations. However, how cells ensure the stability of replication forks in these regions remains a critical challenge. Here, we discovered the pervasive existence of replication forks-associated RNA-DNA hybrids (RF-RDs) within transcriptionally active regions, where they act as a protective barrier against DNA2-mediated nascent DNA degradation and prevent replication fork collapse upon replication stress. Subsequently, the RNA helicase DDX39A dismantles RF-RDs, facilitating proper DNA2-mediated DNA resection and replication fork restart. Excessive dissolution of RF-RDs causes replication fork collapse and genomic instability, while insufficient dissolution of RF-RDs under replication stress increases fork stability, resulting in chemoresistance that can be reversed by eliminating RF-RDs. In summary, we elucidated the prevalence of RF-RDs at replication forks within transcriptionally active regions, revealed their pivotal role in safeguarding replication fork stability, and proposed that targeting RF-RDs holds promise for augmenting chemotherapeutic efficacy.
Project description:Safeguarding replication fork stability in transcriptionally active regions, which require high DNA replication accuracy, is crucial for precise DNA replication and prevention of mutations. However, how cells ensure the stability of replication forks in these regions remains a critical challenge. Here, we discovered the pervasive existence of replication forks-associated RNA-DNA hybrids (RF-RDs) within transcriptionally active regions, where they act as a protective barrier against DNA2-mediated nascent DNA degradation and prevent replication fork collapse upon replication stress. Subsequently, the RNA helicase DDX39A dismantles RF-RDs, facilitating proper DNA2-mediated DNA resection and replication fork restart. Excessive dissolution of RF-RDs causes replication fork collapse and genomic instability, while insufficient dissolution of RF-RDs under replication stress increases fork stability, resulting in chemoresistance that can be reversed by eliminating RF-RDs. In summary, we elucidated the prevalence of RF-RDs at replication forks within transcriptionally active regions, revealed their pivotal role in safeguarding replication fork stability, and proposed that targeting RF-RDs holds promise for augmenting chemotherapeutic efficacy.
Project description:Safeguarding replication fork stability in transcriptionally active regions, which require high DNA replication accuracy, is crucial for precise DNA replication and prevention of mutations. However, how cells ensure the stability of replication forks in these regions remains a critical challenge. Here, we discovered the pervasive existence of replication forks-associated RNA-DNA hybrids (RF-RDs) within transcriptionally active regions, where they act as a protective barrier against DNA2-mediated nascent DNA degradation and prevent replication fork collapse upon replication stress. Subsequently, the RNA helicase DDX39A dismantles RF-RDs, facilitating proper DNA2-mediated DNA resection and replication fork restart. Excessive dissolution of RF-RDs causes replication fork collapse and genomic instability, while insufficient dissolution of RF-RDs under replication stress increases fork stability, resulting in chemoresistance that can be reversed by eliminating RF-RDs. In summary, we elucidated the prevalence of RF-RDs at replication forks within transcriptionally active regions, revealed their pivotal role in safeguarding replication fork stability, and proposed that targeting RF-RDs holds promise for augmenting chemotherapeutic efficacy.
Project description:Safeguarding replication fork stability in transcriptionally active regions, which require high DNA replication accuracy, is crucial for precise DNA replication and prevention of mutations. However, how cells ensure the stability of replication forks in these regions remains a critical challenge. Here, we discovered the pervasive existence of replication forks-associated RNA-DNA hybrids (RF-RDs) within transcriptionally active regions, where they act as a protective barrier against DNA2-mediated nascent DNA degradation and prevent replication fork collapse upon replication stress. Subsequently, the RNA helicase DDX39A dismantles RF-RDs, facilitating proper DNA2-mediated DNA resection and replication fork restart. Excessive dissolution of RF-RDs causes replication fork collapse and genomic instability, while insufficient dissolution of RF-RDs under replication stress increases fork stability, resulting in chemoresistance that can be reversed by eliminating RF-RDs. In summary, we elucidated the prevalence of RF-RDs at replication forks within transcriptionally active regions, revealed their pivotal role in safeguarding replication fork stability, and proposed that targeting RF-RDs holds promise for augmenting chemotherapeutic efficacy.