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Akutsu, M.

Publications and source records attributed to Akutsu, M..

3 recordsLinked to original sources

Caspase cleavage of Influenza A virus M2 disrupts M2-LC3 interaction and regulates virion production

Influenza A virus (IAV) Matrix 2 (M2) protein is an ion channel, required for efficient viral entry and egress. M2 interacts with the small ubiquitin-like LC3 protein through a cytoplasmic C-terminal LC3 interacting region (LIR). Here, we report that M2 is cleaved by caspases, abolishing the M2-LC3 interaction. A crystal structure of the M2 LIR in complex with LC3 indicates the caspase cleavage tetrapeptide motif (82SAVD85) is an unstructured linear motif that does not overlap with the LIR. Furthermore, an IAV mutant expressing a permanently truncated M2, mimicking caspase cleavage, is impaired in M2 plasma membrane transport and produces a significantly attenuated virus. Our results reveal a dynamic regulation of the M2-LC3 interaction by caspases. This highlights the role of host proteases in regulating IAV exit, relating virion production with host cell state.

microbiology↗

Genome sequence of Hydrangea macrophylla and its application in analysis of the double flower phenotype

Owing to its high ornamental value, the double flower phenotype of hydrangea (Hydrangea macrophylla) is one of its most important traits. In this study, genome sequence information was obtained to explore effective DNA markers and the causative genes for double flower production in hydrangea. Single molecule real-time sequencing data followed by a HiC analysis was employed. The resultant haplotype-phased sequences consisted of 3,779 sequences (2.256 Gb in length and N50 of 1.5 Mb), and 18 pseudomolecules comprising 1.08 Gb scaffold sequences along with a high-density SNP genetic linkage map. Using the genome sequence data obtained from two breeding populations, the SNPs linked to double flower loci (Djo and Dsu), were discovered for each breeding population. DNA markers J01 linked to Djo and S01 linked to Dsu were developed, and these could be used successfully to distinguish the recessive double flower allele for each locus respectively. The LEAFY gene was suggested as the causative gene for Dsu, since frameshift was specifically observed in double flower accession with dsu. The genome information obtained in this study will facilitate a wide range of genomic studies on hydrangea in the future.

genomics↗

Wss1 promotes replication stress tolerance by degrading histones.

Timely completion of DNA replication is central to accurate cell division and to the maintenance of genomic stability. However, certain DNA-protein interactions can physically impede DNA replication fork progression. Cells remove or bypass these physical impediments by different mechanisms to preserve DNA macromolecule integrity and genome stability. In Saccharomyces cerevisiae, Wss1, the DNA-protein crosslink repair protease, allows cells to tolerate hydroxyurea-induced replication stress but the underlying mechanism by which Wss1 promotes this function has remained unknown. Here we report that Wss1 provides cells tolerance to replication stress by directly degrading core histone subunits that non-specifically and non-covalently bind to single-stranded DNA. Unlike Wss1-dependent proteolysis of covalent DNA-protein crosslinks, proteolysis of histones does not require Cdc48 nor SUMO-binding activities. Wss1 thus acts as a multi-functional protease capable of targeting a broad range of covalent and non-covalent DNA-binding proteins to preserve genome stability during adverse conditions.

cell biology↗