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The organization of chromatin into self-interacting domains is universal among eukaryotic genomes, though how and why they form varies considerably. Here we report a chromosome-scale reference genome assembly of pepper (Capsicum annuum) and explore its 3D organization through integrating high-resolution Hi-C maps with epigenomic, transcriptomic, and genetic variation data. Chromatin folding domains in pepper are as prominent as TADs in mammals but exhibit unique characteristics. They tend to coincide with heterochromatic regions enriched with retrotransposons and are frequently embedded in loops, which may correlate with transcription factories. Their boundaries are hotspots for chromosome rearrangements but are otherwise depleted for genetic variation. While chromatin conformation broadly affects transcription variance, it does not predict differential gene expression between tissues. Our results suggest that pepper genome organization is explained by a model of heterochromatin-driven folding promoted by transcription factories and that such spatial architecture is under structural and functional constraints.

Direct regeneration of LiFePO4 (LFP), as a promising short-process recycling method, has attracted considerable attention. However, spent materials in industry mainly arise from large-scale mechanical dismantling, which is composed of spent graphite, whereas retired graphite constitutes 30% of mixed materials. Owing to the high oxidation temperature of graphite, a relatively high sintering temperature is selected for graphite removal. However, over-calcined LFP pre-oxidized precursors lead to low recovery of the spent phase. Herein, a purification–lithiation collaborative regeneration method is proposed for preparing precursors with high purity. Assisted by a "tailored" reductive carbon, the crystalline phase was recovered. As a Li-storage cathode, the optimized samples displayed an initial capacity of 133.0 mA h g−1 at 1.0C. Even at a current density of 5.0C, optimized samples showed 112.5 mA h g−1 with 100% capacity retention ratio after 500 cycles. Supported by detailed physical–chemical analysis, the rationally introduced Li–Fe anti-sites could induce the construction of two-dimensional Li-diffusion channels, along with enhanced Li-diffusion behaviors. This work is expected to provide guidance of the direct regeneration process of LFP samples with graphite impurities. [ABSTRACT FROM AUTHOR]

Summary: MicroRNA482/2118 (miR482/2118) is a 22‐nt miRNA superfamily, with conserved functions in disease resistance and plant development. It usually instigates the production of phased small interfering RNAs (phasiRNAs) from its targets to expand or reinforce its silencing effect. Using a new high‐quality reference genome sequence and comprehensive small RNA profiling, we characterized a newly evolved regulatory pathway of miR482/2118 in litchi. In this pathway, miR482/2118 cleaved a novel noncoding trans‐acting gene (LcTASL1) and triggered phasiRNAs to regulate the expression of gibberellin (GA) receptor gene GIBBERELLIN INSENSITIVE DWARF1 (GID1) in trans; another trans‐acting gene LcTASL2, targeted by LcTASL1‐derived phasiRNAs, produced phasiRNAs as well to target LcGID1 to reinforce the silencing effect of LcTASL1. We found this miR482/2118‐TASL‐GID1 pathway was likely involved in fruit development, especially the seed development in litchi. In vivo construction of the miR482a‐TASL‐GID1 pathway in Arabidopsis could lead to defects in flower and silique development, analogous to the phenotype of gid1 mutants. Finally, we found that a GA‐responsive transcription factor, LcGAMYB33, could regulate LcMIR482/2118 as a feedback mechanism of the sRNA‐silencing pathway. Our results deciphered a lineage‐specifically evolved regulatory module of miR482/2118, demonstrating the high dynamics of miR482/2118 function in plants. [ABSTRACT FROM AUTHOR]

Pueraria thomsonii Benth. is a perennial leguminous vine with medicinal and nutritional value. However, rapid postharvest physiological deterioration (PPD) reduces its quality and market value. To detect gene expression levels, the quantitative reverse transcription polymerase chain reaction (qRT-PCR) technique requires stable internal reference genes (IRGs). Our findings indicated that an ethephon (C2H6ClO3P) treatment delayed PPD in P. thomsonii tuberous roots and an RNA-seq analysis revealed a significant number of differentially expressed genes (DEGs). To find stable IRGs for the further identification of the genes associated with delayed PPD in P. thomsonii, eight candidate IRGs of the tuberous roots were screened and assessed using qRT-PCR. The expression stability of these genes was determined and ranked using five different algorithms, including NormFinder, BestKeeper, ΔCt, GeNorm, and ReFinder. Consequently, we identified two genes, PtUBC10 and PtACT7, as the best candidate IRGs for qRT-PCR normalization in P. thomsonii, both exposed to ethephon treatment and in different tissues. Moreover, PtUBC10 was found to be the most stably expressed IRG of P. thomsonii during the ethephon treatment. The findings of this investigation furnish significant insights for future gene expression analyses concerning the delay of PPD via ethephon administration, which could also be used in other tuberous plants. [ABSTRACT FROM AUTHOR]