Explore the vast range of titles available.

Understanding the genetic basis for forage yield traits is essential for forage sorghum and sudangrass hybrid breeding. In this study, we constructed a high-density genetic map using a recombinant inbred line population between sorghum Tx623A and sudangrass Sa using RAD-seq and performed QTL mapping for plant height (PH), stem diameter (SD), tiller number (TN), total shoot fresh weight (FW) and total shoot dry weight (DW). The map consists of 1,065 markers with a total length of 1191.7 cM. A total of 43 QTLs were detected, including three QTLs for PH, eight for SD, ten for TN, ten for FW and twelve for DW. Two QTL clusters contained overlapping QTLs for TN, FW and DW. One cluster (qTN6.2/qFW6/qDW6.1) also overlaps with qTN6.1 and qDW6.2. The sorghum ortholog of a known heterotic biomass gene ARGOS, Sobic.006G092500, was located within all the five QTLs mapped on chromosome 6. Our results showed that a high-density genetic map is useful for dissecting important traits and identifying underlying genes in sorghum and sudangrass hybrid populations.

Significant progress has been made on sorghum transformation in the last decades; however, the transformation process has been constrained by the availability of immature embryos because most of the researchers have utilized immature embryos as favorable explants. Although immature embryos have been proven to be optimal for tissue culture and transformation, isolation of immature embryos is time-consuming, labor-intensive, and limited by warm weather. In this study, we developed an efficient genetic transformation system using mature seeds as explants. The nptII and gus gene, used as the selective marker and report gene respectively, have been co-transformed by particle bombardment. After optimization of tissue culture, the G418 concentration, and transgenic, the average transformation frequency at 13.33% was achieved routinely. The transgenic events and transgene copy numbers were determined by PCR and RT-PCR, respectively. The geneticin selection and GUS staining on T 1 seedlings confirmed that the transgenic plants were heritable. Our results demonstrated that the efficient sorghum transformation system has been established using mature seeds as explants. This transformation system will promote sorghum research on genetic engineering and genome editing without seasonal weather conditions restriction and explant resources restriction.

Protoplasts are commonly used in genetic and breeding research. In this study, the isolation of sorghum protoplasts was optimized and applied to transient gene expression and editing by CRISPR/Cas9. The protoplast was most viable in 0.5 M mannitol, which was the highest of three concentrations after 48- and 72-hours treatments. Using this method we can derive an average of 1.6×10 6 cells which vary from 5 to 22 nm in size. The average transfection of the protoplasts was 68.5% using the PEG-mediated method. The subcellular assays located Sobic.002G279100-GFP and GFP proteins in the cell compartments as predicted bioinformatically. Two CRISPR/Cas9 plasmids were transfected into sorghum protoplasts to screen for an appropriate sgRNA for gene editing. One plasmid can correctly edit the target region using a single protoplast cell as template DNA. Our results indicated that the protoplast assays as optimized are suitable for transient gene expression and sgRNA screening in CRISPR/Cas9 gene editing procedures.

The formation of carbonates is not yet a well-understood process that is biogenic or abiotic origin remains controversial. To obtain further insights on the controls of Mg incorporation in carbonates formed via biogenic process, the impacts of cyanobacteria Synechocystis sp. PCC6803 on carbonates precipitation have been investigated in BG11 medium at different Mg/Ca molar ratios in the laboratory. Initial concentration of Ca 2+ was 0.01 M and Mg/Ca molar ratio was 0, 2, 4, and 6, respectively. The results showed that pH values in the experimental group increased rapidly, greater than those in the control group. Ca 2+ concentration decreased greatly while Mg 2+ concentration was almost unchanged in these two groups. There were significant differences in the sizes, shapes, elemental compositions, and surface morphologies of the mineral precipitates between control group and experimental group analyzed by polarizing microscopy, scanning electron microscopy and energy dispersive X-ray detector. X-ray diffraction result showed that calcite was induced at Mg/Ca molar ratio of 0 and aragonite was induced at Mg/Ca molar ratio of 4 and 6. X-ray diffraction and selected-area electron diffraction results showed the minerals at Mg/Ca molar ratio of 2 were calcite and aragonite. The cracks on the surface of aragonite crystals may be a characteristic of biogenetic aragonite. Thermogravimetric analysis of the carbonate minerals showed that the thermal stability decreased gradually with increasing Mg/Ca molar ratios. These results are useful for further understanding of the formation mechanism of biogenic carbonates in natural condition.

Based on the terminology of “aragonite seas” and “calcite seas”, whether different Mg sources could affect the mineralogy of carbonate sediments at the same Mg/Ca ratio was explored, which was expected to provide a qualitative assessment of the chemistry of the paleo-ocean. In this work, amorphous calcium carbonate (ACC) was prepared by direct precipitation in anhydrous ethanol and used as a precursor to study crystallization processes in MgSO4 and MgCl2 solutions having different concentrations at 60 °C (reaction times 240 and 2880 min). Based on the morphology of the aragonite crystals, as well as mineral saturation indices and kinetic analysis of geochemical processes, it was found that these crystals formed with a spherulitic texture in 4 steps. First, ACC crystallized into columnar Mg calcite by nearly oriented attachment. Second, the Mg calcite changed from columnar shapes into smooth dumbbell forms. Third, the Mg calcite transformed into rough dumbbell or cauliflower-shaped aragonite forms by local dissolution and precipitation. Finally, the aragonite transformed further into spherulitic radial and irregular aggregate forms. The increase in Ca2+ in the MgSO4 solutions compared with the MgCl2 solutions indicates the fast dissolution and slow precipitation of ACC in the former solutions. The phase transition was more complete in the 0.005 M MgCl2 solution, whereas Mg calcite crystallized from the 0.005 M MgSO4 solution, indicating that Mg calcite could be formed more easily in an MgSO4 solution. Based on these findings, aragonite and Mg calcite relative to ACC could be used to provide a qualitative assessment of the chemistry of the paleo-ocean. Therefore, calcite seas relative to high-Mg calcite could reflect a low concentration MgSO4 paleo-ocean, while aragonite seas could be related to an MgCl2 or high concentration of MgSO4 paleo-ocean.

Background Microbial-driven decomposition of plant residues is integral to carbon sequestration in terrestrial ecosystems. Actinobacteria , one of the most widely distributed bacterial phyla in soils, are known for their ability to degrade plant residues in vitro. However, their in situ importance and specific activity across contrasting ecological environments are not known. Here, we conducted three field experiments with buried straw in combination with microcosm experiments with 13 C-straw in paddy soils under different soil fertility levels to reveal the ecophysiological roles of Actinobacteria in plant residue decomposition. Results While accounting for only 4.6% of the total bacterial abundance, the Actinobacteria encoded 16% of total abundance of carbohydrate-active enzymes (CAZymes). The taxonomic and functional compositions of the Actinobacteria were, surprisingly, relatively stable during straw decomposition. Slopes of linear regression models between straw chemical composition and Actinobacterial traits were flatter than those for other taxonomic groups at both local and regional scales due to holding genes encoding for full set of CAZymes, nitrogenases, and antibiotic synthetases. Ecological co-occurrence network and 13 C-based metagenomic analyses both indicated that their importance for straw degradation increased in less fertile soils, as both links between Actinobacteria and other community members and relative abundances of their functional genes increased with decreasing soil fertility. Conclusions This study provided DNA-based evidence that non-dominant Actinobacteria plays a key ecophysiological role in plant residue decomposition as their members possess high proportions of CAZymes and as a group maintain a relatively stable presence during plant residue decomposition both in terms of taxonomic composition and functional roles. Their importance for decomposition was more pronounced in less fertile soils where their possession functional genes and interspecies interactions stood out more. Our work provides new ecophysiological angles for the understanding of the importance of Actinobacteria in global carbon cycling. 3uWhKDWFjqsFeP9DMWUatJ Video abstract

Dynamic chemistry refers to a type of fundamental science that involves precise construction or regulation of reactional, motional, or constitutional dynamics of chemical systems. Under the meticulous design of chemists, the nanoscopic dynamics, either molecular or supramolecular, are managed to scale up to macroscopic dynamic properties. For example, the stimuli‐induced conformational or configurational changes of polymer skeletons result in unexpected functions of polymers, such as self‐healing and shape‐shifting behaviors. This review focuses on how the microscopic dynamics of these molecular components initiate the reversible macroscopic deformation of the corresponding polymer materials upon external stimuli. The self‐healing and shape‐shifting materials are discussed in terms of the subtle molecular design, dynamic reversible mechanisms, and critical roles of the dynamic components in building these materials. Furthermore, this review puts forward the challenges and opportunities for the field of dynamic polymers in both aspects of fundamental chemistry and material fabrication. We hope this review can provide new inspiration for the development of this particular research field.

Tibetan sheep, a dominant livestock species on the Qinghai–Tibet Plateau, is characterized by late sexual maturity and low reproductive efficiency. Although long non-coding RNAs (lncRNAs) are known to play critical regulatory roles in mammalian testicular development and spermatogenesis, their expression dynamics and functions in Tibetan sheep remain poorly understood. In this study, we integrated histological and transcriptomic analyses to profile testicular lncRNAs across three developmental stages: pre-pubertal (3 months), sexually mature (1 year), and adult (3 years). Histological examination showed progressive structural maturation of seminiferous tubules, accompanied by significant increases in testicular weight and serum testosterone levels. RNA sequencing identified 10,857 high-confidence lncRNAs and uncovered extensive reprogramming of the lncRNA transcriptome during sexual maturation, with 7784 lncRNAs differentially expressed between pre-pubertal and post-pubertal stages. Functional enrichment analyses of cis- and antisense-target genes indicated that these lncRNAs were involved in key biological processes, including cell cycle regulation, TGF-β and Hippo signaling pathways, extracellular matrix organization, glycolysis, and apoptosis. Co-expression network analysis further linked upregulated lncRNAs to spermatogenesis-related genes involved in processes such as sperm nuclear condensation (e.g., TNP1) and metabolic support (e.g., PFKP). Our findings demonstrated that lncRNAs coordinate testicular development and spermatogenesis in Tibetan sheep by modulating transcriptional networks, remodeling the cellular microenvironment, and reprogramming energy metabolism. This study provides the first comprehensive atlas of testicular lncRNAs in Tibetan sheep and offers novel insights into the epigenetic regulation of male reproduction in high-altitude mammals.

Background Domesticated chickens have a wide variety of phenotypes, in contrast with their wild progenitors. Unlike other chicken breeds, Xichuan black-bone chickens have blue-shelled eggs, and black meat, beaks, skin, bones, and legs. The breeding history and the economically important traits of this breed have not yet been explored at the genomic level. We therefore used whole genome resequencing to analyze the breeding history of the Xichuan black-bone chickens and to identify genes responsible for its unique phenotype. Results Principal component and population structure analysis showed that Xichuan black-bone chicken is in a distinct clade apart from eight other breeds. Linkage disequilibrium analysis showed that the selection intensity of Xichuan black-bone chickens is higher than for other chicken breeds. The estimated time of divergence between the Xichuan black-bone chickens and other breeds is 2.89 ka years ago. Fst analysis identified a selective sweep that contains genes related to melanogenesis. This region is probably associated with the black skin of the Xichuan black-bone chickens and may be the product of long-term artificial selection. A combined analysis of genomic and transcriptomic data suggests that the candidate gene related to the black-bone trait, EDN3 , might interact with the upstream ncRNA LOC101747896 to generate black skin color during melanogenesis. Conclusions These findings help explain the unique genetic and phenotypic characteristics of Xichuan black-bone chickens, and provide basic research data for studying melanin deposition in animals.