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Jasmonic acid (JA) regulates plant growth, development and stress responses. Coronatine insensitive 1 (COI1) and jasmonate zinc-finger inflorescence meristem-domain (JAZ) proteins form a receptor complex for jasmonoyl-l-isoleucine, a biologically active form of JA. Three COIs (OsCOI1a, OsCOI1b and OsCOI2) are encoded in the rice genome. In the present study, we generated mutants for each rice COI gene using genome editing to reveal the physiological functions of the three rice COIs. The oscoi2 mutants, but not the oscoi1a and oscoi1b mutants, exhibited severely low fertility, indicating the crucial role of OsCOI2 in rice fertility. Transcriptomic analysis revealed that the transcriptional changes after methyl jasmonate (MeJA) treatment were moderate in the leaves of oscoi2 mutants compared to those in the wild type or oscoi1a and oscoi1b mutants. MeJA-induced chlorophyll degradation and accumulation of antimicrobial secondary metabolites were suppressed in oscoi2 mutants. These results indicate that OsCOI2 plays a central role in JA response in rice leaves. In contrast, the assessment of growth inhibition upon exogenous application of JA to seedlings of each mutant revealed that rice COIs are redundantly involved in shoot growth, whereas OsCOI2 plays a primary role in root growth. In addition, a co-immunoprecipitation assay showed that OsJAZ2 and OsJAZ5 containing divergent Jas motifs physically interacted only with OsCOI2, whereas OsJAZ4 with a canonical Jas motif interacts with all three rice COIs. The present study demonstrated the functional diversity of rice COIs, thereby providing clues to the mechanisms regulating the various physiological functions of JA.

Jasmonic acid (JA) regulates plant growth, development, and stress responses. Coronatine insensitive 1 (COI1) and jasmonate ZIM-domain (JAZ) proteins form a receptor complex for jasmonoyl-l-isoleucine (JA-Ile), a biologically active form of JA. Three COIs (OsCOI1a, OsCOI1b, and OsCOI2) are encoded in the rice genome. In the present study, we generated mutants for each rice COI gene using genome editing to reveal the physiological functions of the three rice COIs. The oscoi2 mutants, but not the oscoi1a and oscoi1b mutants, exhibited severely low fertility, indicating the crucial role of OsCOI2 in rice fertility. Transcriptomic analysis revealed that the transcriptional changes after methyl jasmonate (MeJA) treatment were moderate in the leaves of oscoi2 mutants compared to those in the wild-type or oscoi1a and oscoi1b mutants. MeJA-induced chlorophyll degradation and accumulation of antimicrobial secondary metabolites were suppressed in oscoi2 mutants. These results indicate that OsCOI2 plays a central role in JA response in rice leaves. In contrast, assessment of growth inhibition upon exogenous application of JA to seedlings of each mutant revealed that rice COIs are redundantly involved in shoot growth, whereas OsCOI2 plays a primary role in root growth. In addition, a co-immunoprecipitation assay showed that OsJAZ2 and OsJAZ5 containing divergent Jas motifs physically interacted only with OsCOI2, whereas OsJAZ4 with a canonical Jas motif interacts with all three rice COIs. The present study demonstrated the functional diversity of rice COIs, thereby providing clues to the mechanisms regulating the various physiological functions of JA.

Jasmonic acid (JA) and its biologically active form jasmonoyl-L-isoleucine (JA-Ile) regulate defense responses to various environmental stresses and developmental processes in plants. JA and JA-Ile are synthesized from α-linolenic acids derived from membrane lipids via 12-oxo-phytodienoic acid (OPDA). In the presence of JA-Ile, the COI1 receptor physically interacts with JAZ repressors, leading to their degradation, resulting in the transcription of JA-responsive genes by MYC transcription factors. Although the biosynthesis of JA-Ile is conserved in vascular plants, it is not recognized by COI1 in bryophytes and is not biologically active. In the liverwort Marchantia polymorpha, dinor-OPDA (dn-OPDA), a homolog of OPDA with two fewer carbons, and its isomer dn-iso-OPDA accumulate after wounding and are recognized by COI1 to activate downstream signaling. The moss Calohypnum plumiforme produces the antimicrobial-specialized metabolites, momilactones. It has been reported that JA and JA-Ile are not detected in C. plumiforme and that OPDA, but not JA, can induce momilactone accumulation and the expression of these biosynthetic genes, suggesting that OPDA or its derivative is a biologically active molecule in C. plumiforme that induces chemical defense. In the present study, we investigated the biological functions of OPDA and its derivatives in C. plumiforme. Searching for the components potentially involving oxylipin signaling from transcriptomic and genomic data revealed that two COI1, three JAZ, and two MYC genes were present. Quantification analyses revealed that OPDA and its isomer iso-OPDA accumulated in larger amounts than dn-OPDA and dn-iso-OPDA after wounding. Moreover, exogenously applied OPDA, dn-OPDA, or dn-iso-OPDA induced the transcription of JAZ genes. These results imply that OPDA, dn-OPDA, and/or their isomers potentially act as biologically active molecules to induce the signaling downstream of COI1-JAZ. Furthermore, co-immunoprecipitation analysis showed the physical interaction between JAZs and MYCs, indicating the functional conservation of JAZs in C. plumiforme with other plants. These results suggest that COI1-JAZ-MYC mediated signaling is conserved and functional in C. plumiforme., Scheme 1 Chemical synthesis of iso-OPDA.

Memory-and-Disk caching is a common caching mechanism for temporal output in Apache Spark. However, it causes performance degradation when memory usage has reached its limit because of the Spark's LRU (Least Recently Used) based cache management. Existing studies have reported that replacement of LRU-based cache mechanism to LRC (Least Reference Count) based one that is a more accurate indicator of the likelihood of future data access. However, frequently used partitions cannot be determined because Spark accesses all of partitions for user-driven RDD operations, even if partitions do not include necessary data. In this paper, we propose a cache management method that enables allocating necessary partitions to the memory by introducing the bloom filter into existing methods. The bloom filter prevents unnecessary partitions from being processed because partitions are checked whether required data is contained. Furthermore, frequently used partitions can be properly determined by measuring the reference count of partitions. We implemented two architecture types, the driver-side bloom filter and the executor-side bloom filter, to consider the optimal place of the bloom filter. Evaluation results showed that the execution time of the driver-side implementation was reduced by 89% in a filter-test benchmark based on the LRC-based method.

Apache Spark caches reusable data into memory/disk. From our preliminary evaluation, we have found that a memory-and-disk caching is ineffective compared to disk-only caching when memory usage has reached its limit. This is because a thrashing state involving frequent data move between the memory and the disk occurs for a memory-and-disk caching. Spark has introduced a thrashing avoidance method for a single RDD (Resilient Distributed Dataset), but it cannot be applied to workloads using multiple RDDs because prior detection of the dependencies between the RDDs is difficult due to unpredictable access pattern. In this paper, we propose a thrashing avoidance method for such workloads. Our method adaptively modifies the cache I/O behavior depending on characteristics of the workload. In particular, caching data are directly written to the disk instead of the memory if cached data are frequently moved from the memory to the disk. Further, cached data are directly returned to the execution-memory instead of the storage-memory if cached data in the disk are required. Our method can adaptively select the optimal cache I/O behavior by observing workload characteristics at runtime instead of analyzing the dependence among RDDs. Evaluation results showed that execution time was reduced by 33% for KMeans using the modified Spark memory-and-disk caching rather than the original.

Wool and poly ( ethylene terephthalate) fabrics and film were treated with low-tem perature plasmas of helium/argon or acetone/argon under atmospheric pressure for 10 to 180 seconds. Although argon itself cannot independently generate a plasma under atmospheric pressure by applying high frequency voltage, it is easily generated by adding a small quantity of helium or acetone to argon gas. Wettability of the fabrics and surface tension of the film increased considerably with the treatment within 30 seconds. ESCA analysis was used to elucidate the surface chemical composition of fibers treated with atmospheric low-temperature plasma. Relative O1 s intensity in creased considerably and oxygen was incorporated in the form of —CO— and —COO— on the fiber surface. From these results, it appears that low-temperature plasma by atmospheric pressure discharge is effective for modifying the polymer surface, as it acts in the same fashion as low-temperature plasma by glow discharge.

V-1 is a 12 kDa protein containing 2.5 copies of the ankyrin repeat, which has been demonstrated to be required for protein-protein interactions. Recently we have for the first time reported that stable overexpression of V-1 enhances mRNA expression of catecholamine synthesizing enzymes in PC12D cells, and as a result, catecholamine production is upregulated. GTP cyclohydrolase I (GCH) is the enzyme in the first and rate-limiting step for the biosynthesis of tetrahydrobiopterin (BH4) which is an essential cofactor for tyrosine hydroxylase. In the present study, to examine further the function of V-1 in control of the BH4 biosynthesis, we assayed BH4 content and GCH enzyme activity in V-1-overexpressing PC12D cell clones. It was shown that both BH4 content and GCH enzyme activity were increased in V-1-verexpressing PC12D cell clones. It was also revealed that V-1-overexpression caused augmentation of both the GCH protein and mRNA expression and the cAMP-responsive element (CRE) dependent transcription. Furthermore, promoter analysis showed an increased activity in the construct with 150 bp of promoter region of the human GCH gene in the V-1-overexpressing clones. These results suggest that V-1 promotes GCH gene expression via a CRE-dependent transcription to positively control the BH4 biosynthesis in catecholaminergic cells.