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Mori, A.

Publications and source records attributed to Mori, A..

2 recordsLinked to original sources

Development of digital Hi-C assay

Abstracts Enhancers are genomic elements and contain all necessary cis-regulatory contexts. Such enhancers are convened to the appropriate promoter of target genes for gene regulations even though the enhancers and the promoters are apart a few mega-base pairs away from each other. In addition to physical distance, nucleotide mutations in enhancers influence a partial group of the target genes. Those make it more complicated to reveal the paired relationship between enhancer and promoter of target genes. Recently, advanced computational approaches are employed to predict such interactions. One approach requires a large number of different high-throughput datasets to predict such interactions; however, in practical aspects, all datasets for tissues and conditions of interest are not available. Whereas the alternative approach requires only genome sequences for particular predictions, their predictions are insufficient for practical applications. We address those issues by developing the digital Hi-C assay with a transformer-algorithm basis. This assay allows us to create models from simple/small/limited sequence-based datasets only. We apply the trained models to be able to identify long-distance interactions of genomic loci and three-dimensional (3D) genomic architectures in any other tissue/cell datasets; additionally, we demonstrated the predictions of genomic contexts by analysing the prediction patterns around the target locus in the three following genomic-context problems: enhancer-promoter interactions (i.e., promoter-capture Hi-C), the CTCF-enriched regions, and TAD-boundary regions. Because our approach adopted a sequence-based approach, we can predict the long-distance interactions of genomic loci by using the genomic sequences of the users interest (e.g., input sequences from high-throughput assay datasets such as ATAC-seq and ChIP-seq assays). Consequently, we provide an opportunity to predict interactions of genomic loci from a minimum dataset.

bioinformatics↗

The role of rice SOG1 and SOG1-like in DNA damage response

Higher plants are constantly exposed to environmental stresses, and therefore complicated defense systems, including DNA damage response (DDR) and DNA repair systems, have developed to protect plant cells. In Arabidopsis, the transcription factor SUPPRESSOR OF GAMMA RESPONSE 1 (SOG1) has been reported to play a key role in DDR. Here, we focus on DDR in rice--thought to be a simpler system compared with Arabidopsis due to lack of induction of endocycle even under DNA damage stress. Rice SOG1 (OsSOG1) and SOG1-like (OsSGL) were identified as putative AtSOG1 orthologs with complete or partial conservation of the serine-glutamine (SQ) motifs involved in activation via phosphorylation. In addition to OsSOG1- or OsSGL-knockout mutants, OsSOG1 non-phosphorylatable mutants (OsSOG1-7A) were generated by homologous recombination-mediated gene targeting. Based on DNA damage susceptibility and transcriptome analysis using these mutants, we demonstrated that OsSOG1, but not OsSGL, plays a central role in the DDR and DNA repair. OsSOG1 regulated target genes via CTT (N)7 AAG motifs reported previously as AtSOG1 recognition sites. The loss of transcription activities and DNA damage tolerance of OsSOG1-7A was not complete compared with OsSOG1-knockout mutants, raising the possibility that another phosphorylation site might be involved in the activation of OsSOG1. Furthermore, our findings have highlighted differences in SOG1-mediated DDR between rice and Arabidopsis, especially regarding induction of cell-cycle arrest and endocycle arrest, revealing rice-specific DDR mechanisms. One sentence summaryRice transcription factor SUPPRESSOR OF GAMMA RESPONSE 1 controls DNA damage response and DNA repair through activation via phosphorylation and the direct regulation of expression of numerous genes.

plant biology↗