The kiwifruit (Actinidia chinensis) is an economically and nutritionally important fruit crop with remarkably high vitamin C content. Here we report the draft genome sequence of a heterozygous kiwifruit, assembled from ~140-fold next-generation sequencing data. The assembled genome has a total length of 616.1 Mb and contains 39,040 genes. Comparative genomic analysis reveals that the kiwifruit has undergone an ancient hexaploidization event (γ) shared by core eudicots and two more recent whole-genome duplication events. Both recent duplication events occurred after the divergence of kiwifruit from tomato and potato and have contributed to the neofunctionalization of genes involved in regulating important kiwifruit characteristics, such as fruit vitamin C, flavonoid and carotenoid metabolism. As the first sequenced species in the Ericales, the kiwifruit genome sequence provides a valuable resource not only for biological discovery and crop improvement but also for evolutionary and comparative genomics analysis, particularly in the asterid lineage.

Based on abscisic acid (ABA) inhibition of seed germination and seedling growth assays, we isolated an ABA overly sensitive mutant (abo4-1) caused by a mutation in the Arabidopsis thaliana POL2a/TILTED1(TIL1) gene encoding a catalytic subunit of DNA polymerase «. The dominant, ABA-insensitive abi1-1 or abi2-1 mutations suppressed the ABA hypersensitivity of the abo4-1 mutant. The abo4/til1 mutation reactivated the expression of the silenced Athila retrotransposon transcriptional silent information (TSI) and the silenced 35S-NPTII in the ros1 mutant and increased the frequency of somatic homologous recombination (HR) ;60-fold. ABA upregulated the expression of TSI and increased HR in both the wild type and abo4-1. MEIOTIC RECOMBINATION11 and GAMMA RESPONSE1, both of which are required for HR and double-strand DNA break repair, are expressed at higher levels in abo4-1 and are enhanced by ABA, while KU70 was suppressed by ABA. abo4-1 mutant plants are sensitive to UV-B and methyl methanesulfonate and show constitutive expression of the G2/Mspecific cyclin CycB1;1 in meristems. The abo4-1 plants were early flowering with lower expression of FLOWER LOCUS C and higher expression of FLOWER LOCUS T and changed histone modifications in the two loci. Our results suggest that ABO4/POL2a/TIL1 is involved in maintaining epigenetic states, HR, and ABA signaling in Arabidopsis.

This review covers the use of 2-azaallyl anions, 2-azaallyl cations, and 2-azaallyl radicals in organic synthesis up through June 2018. Particular attention is paid to both foundational studies and recent advances over the past decade involving semistabilized and nonstabilized 2-azaallyl anions as key intermediates in various carbon–carbon and carbon–heteroatom bond-forming processes. Both transition-metal-catalyzed and transition-metal-free transformations are covered. Azomethine ylides, which have received significant attention elsewhere, are discussed briefly with the primary focus on critical comparisons with 2-azaallyl anions in regard to generation and use.

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