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The study of genomic structural evolution associated with accelerated evolutionary rates that result in avoidance of meltdown and increase biodiversity is becoming ever more possible as the number of available plastomes increases. To more comprehensively analyze rate heterogeneity among monocots and within Poaceae, we sequenced plastomes from four Poaceae species, combined them with publicly available data from ~200 plastomes, and conducted comparative analyses to quantify the pattern of rate heterogeneity between different lineages, functional groups, and periods of evolutionary time. We compared structural differences across the Poaceae to quantify how changes in plastome size correspond to different genomic subunits and the evolution of IR–SC junction boundaries. The substitution rates among ancestral Poaceae were inferred to be exceptionally rapid compared to other monocots but slowed after divergence into extant lineages, which could not be sufficiently explained by positive selection. As such, rapid rates in the ancestral lineage leading to Poaceae might be more closely linked to large‐scale structural changes like the loss of ycf1 and ycf2. The total increase in plastome size across Poaceae was positively correlated with the total length of intergenic spacers, tandem repeats, and dispersed repeats as well as large single copy, and inverted repeats (IRs). The continuous evolution of IR–SC junction boundaries was asynchronous with sizes of total genome and subunits across Poaceae. Future work is needed to better understand what factors in ancestral Poaceae evolved to harness such rapid rates of plastome evolution, avoid a mutational meltdown, and escape the stagnation of strong purifying selection as well as if these factors could be utilized to synthetically control rates. Highlights: Extensive sampling covering all monocotyledonous orders and subfamilies of Poaceae to compare different levels of plastome evolutionary rates heterogeneity.Comprehensively revealed the clade‐specific patterns of plastomes size variations among Poaceae subfamilies.Confirmed the distances of genes to IR–SC boundaries were effective for phylogeny, species identification, and maternal tracing of Poaceae species. [ABSTRACT FROM AUTHOR]

Effective detection and removal of Cr(VI) from various waters still remains a severe challenge. Given the aggregation-induced emission (AIE) and photo-induced electron transfer (PET) effect, a few MOFs perform dual-functional fluorescence sensing and photochemical reduction towards Cr(VI). Nevertheless, how to enhance photoluminescence ability and photocatalytic reduction efficiency simultaneously has been rarely studied and reported. Here, a novel dual-emissive platform of Tb@Zr-MOF with high water stability was ingeniously designed by anchoring lanthanide Tb3+ ions in a Zr(IV)-bipyridine framework. Owing to the greatly promoted PET effect, Tb@Zr-MOF exhibits a unique double-enhancement feature compared to the pristine Zr-MOF. After Tb3+ ions were immobilized by carboxyl O atoms, Tb@Zr-MOF emits a typical bright green fluorescence signal of lanthanide metal Tb3+ through the "antenna effect". Notably, Tb@Zr-MOF can be deployed as a self-calibrating photochemical sensor for high-precision fluorescence quenching detection of Cr2O72− ions, showing a rather high Ksv value of 8.093 × 104 M−1 and ultra-low detection limit of 4.03 ppb (17.6 ppb for pristine Zr-MOF). Moreover, the highly efficient PET process combined with an appropriate energy band structure, i.e., the rather negative CB potential confers Tb@Zr-MOF excellent ability to photochemically reduce high-oxidation-state Cr(VI) ions under UV light, with rather a high reduction efficiency of up to 97.5% (1.46 times of pristine Zr-MOF) just within 60 min. Prominently, the highly efficient PET effect from organic modules of Zr-MOF to anchored Tb3+ ions was confirmed by modeling the ground state and excited states of Tb@Zr-MOF using DFT and TD-DFT. This study innovatively combines porous MOFs and the lanthanide metal ion anchoring technique to provide a feasible strategy for improving the existing dual-functional MOF-based fluorescence sensing and photocatalytic platforms. [ABSTRACT FROM AUTHOR]

Since the endosymbiont origin from α‐Proteobacteria, mitochondrial genomes have undergone extremely divergent evolutionary trajectories among eukaryotic lineages. Compared with the relatively compact and conserved animal mitochondrial genomes, plant mitochondrial genomes have many unique features, especially their large and complex genomic arrangements. The sizes of fully sequenced plant mitochondrial genomes span over a 100‐fold range from 66 kb in Viscum scurruloideum to 11 000 kb in Silene conica. In addition to the typical circular structure, some species of plants also possess linear, and even multichromosomal, architectures. In contrast with the thousands of fully sequenced animal mitochondrial genomes and plant plastid genomes, only around 200 fully sequenced land plant mitochondrial genomes have been published, with many being only draft assemblies. In this review, we summarize some of the known novel characteristics found in plant mitochondrial genomes, with special emphasis on multichromosomal structures described in recent publications. Finally, we discuss the future prospects for studying the inheritance patterns of multichromosomal plant mitochondria and examining architectural variation at different levels of taxonomic organization—including at the population level. [ABSTRACT FROM AUTHOR]