Double-stemmed and split structural variants of fluorescent RNA Mango aptamers.

Aptamers with fluorogenic ligands are emerging as useful tools to quantify and track RNA molecules. The RNA Mango family of aptamers have a useful combination of tight ligand binding, bright fluorescence, and small size. However, the simple structure of these aptamers, with a single base-paired stem capped by a G-quadruplex, can limit the sequence and structural modifications needed for many use-inspired designs. Here we report new structural variants of RNA Mango that have two base-paired stems attached to the quadruplex. Fluorescence saturation analysis of one of the double-stemmed constructs showed a maximum fluorescence that is ∼75% brighter than the original single-stemmed Mango I. A small number of mutations to nucleotides in the tetraloop-like linker of the second stem were subsequently analyzed. The effect of these mutations on the affinity and fluorescence suggested that the nucleobases of the second linker do not directly interact with the fluorogenic ligand (TO1-biotin), but may instead induce higher fluorescence by indirectly altering the ligand properties in the bound state. The effects of the mutations in this second tetraloop-like linker indicate the potential of this second stem for rational design and reselection experiments. Additionally, we demonstrated that a bimolecular mango designed by splitting the double-stemmed Mango can function when two RNA molecules are cotranscribed from different DNA templates in a single in vitro transcription. This bimolecular Mango has potential application in detecting RNA-RNA interactions. Together, these constructs expand the designability of the Mango aptamers to facilitate future applications of RNA imaging.

A Change of Pace: Record Photoresponse through Spirooxazine Confinement in a Metal-Organic Matrix.

Modern and upcoming high-speed optoelectronics as well as secure data storage or solar energy harvesting technologies integrating stimuli-responsive materials fully rely on the fundamental concept of rapid transitions between discrete states possessing different properties. Relatively slow transition kinetics between those states for commonly used classes of photochromic compounds in solution or bulk solids severely restrict the applicability of stimuli-responsive materials for device development. Herein, we report a multivariate strategy based on a photochromic spirooxazine derivative, coordinatively integrated in the solvent-free confined space of a solid-state matrix, such as a metal-organic framework (MOF), for the first time, resulting in the fastest photoresponse reported for any solid-state material to date. The photoisomerization rate for the developed photochromic material was estimated to be 126 s-1, surpassing any literature reports to the best of our knowledge. We also shed light on the fundamentals of the correlation between framework topology, the nature of organic linkers, and the presence/absence of organic solvent within the scaffold voids on the material photoresponse using a series of isoreticular frameworks. Overall, the presented conceptual approach allows for tailoring the isomerization kinetics of photochromic molecules in the solid state over a range of 4 orders of magnitude-an unprecedented span that provides a pathway for addressing challenges associated with the response rate and photoisomerization, which are key criteria in stimuli-responsive material development.

Friends or Foes: Fundamental Principles of Th-Organic Scaffold Chemistry Using Zr-Analogs as a Guide.

The fundamental interest in actinide chemistry, particularly for the development of thorium-based materials, is experiencing a renaissance owing to the recent and rapidly growing attention to fuel cycle reactors, radiological daughters for nuclear medicine, and efficient nuclear stockpile development. Herein, we uncover fundamental principles of thorium chemistry on the example of Th-based extended structures such as metal-organic frameworks in comparison with the discrete systems and zirconium extended analogs, demonstrating remarkable over two-and-half-year chemical stability of Th-based frameworks as a function of metal node connectivity, amount of defects, and conformational linker rigidity through comprehensive spectroscopic and crystallographic analysis as well as theoretical modeling. Despite exceptional chemical stability, we report the first example of studies focusing on the reactivity of the most chemically stable Th-based frameworks in comparison with the discrete Th-based systems such as metal-organic complexes and a cage, contrasting multicycle recyclability and selectivity (>97%) of the extended structures in comparison with the molecular compounds. Overall, the presented work not only establishes the conceptual foundation for evaluating the capabilities of Th-based materials but also represents a milestone for their multifaceted future and foreshadows their potential to shape the next era of actinide chemistry.

Role of Transporters and Enzymes in Metabolism and Distribution of 4-Chlorokynurenine (AV-101).

4-Chlorokynurenine (4-Cl-KYN, AV-101) is a prodrug of a NMDA receptor antagonist and is in clinical development for potential CNS indications. We sought to further understand the distribution and metabolism of 4-Cl-KYN, as this information might provide a strategy to enhance the clinical development of this drug. We used excretion studies in rats, in vitro transporter assays, and pharmacogenetic analysis of clinical trial data to determine how 4-Cl-KYN and metabolites are distributed. Our data indicated that a novel acetylated metabolite (N-acetyl-4-Cl-KYN) did not affect the uptake of 4-Cl-KYN across the blood-brain barrier via LAT1. 4-Cl-KYN and its metabolites were found to be renally excreted in rodents. In addition, we found that N-acetyl-4-Cl-KYN inhibited renal and hepatic transporters involved in excretion. Thus, this metabolite has the potential to limit the excretion of a range of compounds. Our pharmacogenetic analysis found that a SNP in N-acetyltransferase 8 (NAT8, rs13538) was linked to levels of N-acetyl-4-Cl-KYN relative to 4-Cl-KYN found in the plasma and that a SNP in SLC7A5 (rs28582913) was associated with the plasma levels of the active metabolite, 7-Cl-KYNA. Thus, we have a pharmacogenetics-based association for plasma drug level that could aid in the drug development of 4-Cl-KYN and have investigated the interaction of a novel metabolite with drug transporters.

Temperature-induced mobility in octacalcium phosphate impacts crystal symmetry: water dynamics studied by NMR crystallography.

Octacalcium phosphate (OCP, Ca8(PO4)4(HPO4)2·5H2O) is a notable calcium phosphate due to its biocompatibility, making it a widely studied material for bone substitution. It is known to be a precursor of bone mineral, but its role in biomineralisation remains unclear. While the structure of OCP has been the subject of thorough investigations (including using Rietveld refinements of X-ray diffraction data, and NMR crystallography studies), important questions regarding the symmetry and H-bonding network in the material remain. In this study, it is shown that OCP undergoes a lowering of symmetry below 200 K, evidenced by 1H, 17O, 31P and 43Ca solid-state NMR experiments. Using ab initio molecular-dynamics (MD) simulations and gauge including projected augmented wave (GIPAW) DFT calculations of NMR parameters, the presence of rapid motions of the water molecules in the crystal cell at room temperature is proved. This information leads to an improved description of the OCP structure at both low and ambient temperatures, and helps explain long-standing issues of symmetry. Remaining challenges related to the understanding of the structure of OCP are then discussed.

Impact of Share 35 liver transplantation allocation in Australia and New Zealand.

Patients with high model for end-stage liver disease (MELD) scores waiting for liver transplantation in Australia and New Zealand (ANZ) have had limited access to deceased donor livers and therefore binational sharing of livers, for patients with a MELD score ≥35 was introduced in February 2016. Waiting list mortality, post-transplant outcomes and intention-to-treat survival were compared between patients whose MELD score reached 35 on the waiting list between October 2013 and April 2015 (Pre-Share 35 group, n = 23) and patients who were Share 35 listed between February 2016 and May 2022 (Share 35 group, n = 112). There was significantly reduced waiting list mortality in share 35 listed patients in comparison to the pre-Share 35 group (11.7% vs. 52.2%, OR .120 95% CI .044-.328, P < .001). Post-transplant patient and graft survival were not significantly different between the groups (5-year patient survival 82% vs. 84%, P = .991, 5-year graft survival 82% vs. 76%, P = .543). Intention-to-treat survival was superior in the Share 35 group (HR .302, 95% CI .149-.614, P < .001). Introduction of Share 35 in ANZ resulted in a 78% risk reduction in waiting list mortality, equivalent post-transplant survival and an improvement in intention-to-treat survival.

Identification of highly potent and selective HTRA1 inhibitors.

High temperature requirement A serine peptidase 1 (HTRA1) is a serine protease involved in an array of signaling pathways. It is also responsible for the regulation of protein aggregates via refolding, translocation, and degradation. It has subsequently been found that runaway proteolytic HTRA1 activity plays a role in a variety of diseases, including Age-Related Macular Degeneration (AMD), osteoarthritis, and Rheumatoid Arthritis. Selective inhibition of serine protease HTRA1 therefore offers a promising new strategy for the treatment of these diseases. Herein we disclose structure-activity-relationship (SAR) studies which identify key interactions responsible for binding affinity of small molecule inhibitors to HTRA1. The study results in highly potent molecules with IC50's less than 15 nM and excellent selectivity following a screen of 35 proteases.

Redox-Active Carboranyl Diphosphine as an Electron and Proton Transfer Agent.

In this work, we report the first example of the PCET reactivity for a boron cluster compound, the zwitterionic nido-carboranyl diphosphonium derivative 7-P(H)tBu2-10-P(H)iPr2-nido-C2B10H10. This main-group reagent efficiently transfers two electrons and two protons to quinones to yield hydroquinones and regenerate a neutral closo-carboranyl diphosphine, 1-PtBu2-2-PiPr2-closo-C2B10H10. As we have previously reported the conversion of this closo-carboranyl diphosphine into the zwitterionic nido- derivative upon reaction with main group hydrides, the transformation reported herein represents a complete synthetic cycle for the metal-free reduction of quinones, with the redox-active carboranyl diphosphine scaffold acting as a mediator. The proposed mechanism of this reduction, based on pKa determination, electrochemical studies, and kinetic isotope effect determination, involves the electron transfer from the nido- cluster to the quinone coupled with the delivery of protons.

Sensitivity of Mild Hydrothermal Synthesis to the Reaction Conditions: Targeting Mixed-Metal Hexagonal Tungsten Bronze Fluorides AxM2+xM3+(1-x)F3 to Investigate Their Magnetic Behavior.

The synthesis of five quaternary hexagonal tungsten bronze (HTB) fluorides, AxM2+xM3+(1-x)F3, (A = Cs and Rb; M2+ = Co2+, Ni2+, and Zn2+; and M3+ = V3+) via a mild hydrothermal route is reported. The crystal structures and compositions were determined using a combination of single-crystal X-ray diffraction, Rietveld refinement of powder X-ray diffraction data, and inductively coupled plasma optical emission spectroscopy analysis. This study highlights the sensitivity of the mild hydrothermal method on the reaction temperature, solvent system, and quantity of starting reagents that directly influence the selective synthesis of kinetically stabilized fluoride materials, including hydrated fluorides, ß-pyrochlores, and HTB. The magnetic susceptibility and isothermal magnetization data for all five compounds were collected, which revealed the existence of a strong antiferromagnetic component in these phases. The presence of the Kagome layer in the structure results in geometrical frustration and leads to frustration indexes ranging from 7 to 13 for these compounds.

Flux Synthesis of Alkaline-Earth Lanthanide Borates as Potential Nuclear Waste Forms.

Neodymium is typically considered the best surrogate for trivalent americium and can be used to identify Am3+ containing materials that are likely to form. We have explored the alkaline-earth lanthanide borate phase space using alkaline-earth halide/carbonate fluxes. This resulted in the synthesis of new compounds AE5Ln(BO3)4X (AE = Ca, Sr; Ln = Pr, Nd, Eu, Tb; X = Cl, Br) and AE3Ln2(BO3)4 (AE = Sr, Ba; Ln = Pr, Nd) as well as the synthesis of two compounds of Ba8Ln2(BO3)6(B2O5) (Ln = Eu, Tb) crystallizing in a new structure type. Ba8Ln2(BO3)6(B2O5) crystallizes in the space group P21/n with lattice parameters a = 8.6002(3) Å, b = 7.9245(3) Å, c = 17.6697(7) Å, and ß = 91.3560(10)° for the Eu analogue, and the structure contains isolated LnO8 polyhedra connected into a framework by BO3 and B2O5 units. The fluorescence emission spectra of AE5Ln(BO3)4X (AE = Ca, Sr; Ln = Eu, Tb; X = Cl, Br) and Ba8Ln2(BO3)6(B2O5) (Ln = Eu, Tb) are reported.

China's response to a national land-system sustainability emergency.

China has responded to a national land-system sustainability emergency via an integrated portfolio of large-scale programmes. Here we review 16 sustainability programmes, which invested US$378.5 billion (in 2015 US$), covered 623.9 million hectares of land and involved over 500 million people, mostly since 1998. We find overwhelmingly that the interventions improved the sustainability of China's rural land systems, but the impacts are nuanced and adverse outcomes have occurred. We identify some key characteristics of programme success, potential risks to their durability, and future research needs. We suggest directions for China and other nations as they progress towards the Sustainable Development Goals of the United Nations' Agenda 2030.

Preoperative Anemia and Postoperative Outcomes in Cardiac Surgery: A Mediation Analysis Evaluating Intraoperative Transfusion Exposures.

BACKGROUND: Preoperative anemia is associated with adverse outcomes in cardiac surgery, yet it remains unclear what proportion of this association is mediated through red blood cell (RBC) transfusions. METHODS: This is a historical observational cohort study of adults undergoing coronary artery bypass grafting or valve surgery on cardiopulmonary bypass at an academic medical center between May 1, 2008, and May 1, 2018. A mediation analysis framework was used to evaluate the associations between preoperative anemia and postoperative outcomes, including a primary outcome of acute kidney injury (AKI). Intraoperative RBC transfusions were evaluated as mediators of preoperative anemia and outcome relationships. The estimated total effect, average direct effect of preoperative anemia, and percent of the total effect mediated through transfusions are presented with 95% confidence intervals and P -values. RESULTS: A total of 4117 patients were included, including 1234 (30%) with preoperative anemia. Overall, 437 of 4117 (11%) patients went on to develop AKI, with a greater proportion of patients having preoperative anemia (219 of 1234 [18%] vs 218 of 2883 [8%]). In multivariable analyses, the presence of preoperative anemia was associated with increased postoperative AKI (6.4% [4.2%-8.7%] absolute difference in percent with AKI, P < .001), with incremental decreases in preoperative hemoglobin concentrations displaying greater AKI risk (eg, 11.9% [6.9%-17.5%] absolute increase in probability of AKI for preoperative hemoglobin of 9 g/dL compared to a reference of 14 g/dL, P < .001). The association between preoperative anemia and postoperative AKI was primarily due to direct effects of preoperative anemia (5.9% [3.6%-8.3%] absolute difference, P < .001) rather than mediated through intraoperative RBC transfusions (7.5% [-4.3% to 21.1%] of the total effect mediated by transfusions, P = .220). Preoperative anemia was also associated with longer hospital durations (1.07 [1.05-1.10] ratio of geometric mean length of stay, P < .001). Of this total effect, 38% (22%, 62%; P < .001) was estimated to be mediated through subsequent intraoperative RBC transfusion. Preoperative anemia was not associated with reoperation or vascular complications. CONCLUSIONS: Preoperative anemia was associated with higher odds of AKI and longer hospitalizations in cardiac surgery. The attributable effects of anemia and transfusion on postoperative complications are likely to differ across outcomes. Future studies are necessary to further evaluate mechanisms of anemia-associated postoperative organ injury and treatment strategies.

Effect of fasedienol (PH94B) pherine nasal spray and steroidal hormones on electrogram responses and autonomic nervous system activity in healthy adult volunteers.

OBJECTIVE: Fasedienol (PH94B) is a pherine compound formulated as a nasal spray that is hypothesized to regulate olfactory-amygdala circuits of fear and anxiety. Fasedienol's effect on the local electrogram of nasal chemosensory neurons (EGNR) and autonomic nervous system (ANS) responses versus steroidal hormones and controls in healthy adults is reported. METHODS: Eight males and 8 females randomly received aerosolized control (propylene glycol) and study drugs (fasedienol, 17ß-estradiol, progesterone, cortisol, and testosterone, 0.4 µg each in propylene glycol) onto the nasal septum mucosal lining at 30-min intervals over 2 sessions. EGNR was continuously monitored; autonomic parameters were recorded before and after administration. RESULTS: Fasedienol significantly increased EGNR amplitude (males: 5.0 vs. 0.6 mV, p < 0.001; females:5.7 vs. 0.6 mV, p < 0.001), and rapidly reduced respiratory rate (p < 0.05), heart rate (p < 0.01), and electrodermal activity (p < 0.05) versus control. EGNR and ANS responses after steroidal hormone administration were similar to control. 81% reported feeling less tense/more relaxed after receiving fasedienol, but not after receiving either control or steroidal hormones. CONCLUSIONS: Intranasal fasedienol, but not control or steroidal hormones, activated EGNR and rapidly reduced ANS responses, consistent with sympatholytic effects. Combined with subjective reports, results suggest fasedienol may provide acute relief in anxiety conditions.

Assessment of Perioperative Protamine Reactions in Patients With Fish Allergies: A Retrospective Observational Study.

OBJECTIVES: To retrospectively assess the incidence and severity of perioperative protamine reactions in adult patients with documented history of fish allergy. DESIGN: Retrospective observational study. SETTING: Large academic tertiary referral center. PARTICIPANTS: Adults with fish allergies undergoing surgeries involving protamine, between January 1, 2008, and March 1, 2018. INTERVENTIONS: Perioperative protamine administration in patients with documented fish allergy. MEASUREMENTS AND MAIN RESULTS: Perioperative protamine and anaphylactic reactions were reviewed. A diagnosis of anaphylaxis or protamine reaction was based on clinical suspicion, perioperative events, and postoperative evaluations. Among 214 patients, 2 cases (<1%) of anaphylaxis or protamine reactions occurred. Cardiac procedures were most common (67%). The median intraoperative heparin dosage was 46,000 IU, and the median protamine dosage was 310 mg. Nearly all patients (99%) were admitted to the intensive care unit postoperatively, with a median hospital stay of 6.5 days (interquartile range, 5.2-14.6 days). There were 3 deaths (1%) within 30 days, and 15 (7%) within 1 year. CONCLUSIONS: The study findings suggest that in patients with a history of fish allergy, cross-reactivity with protamine is unlikely, as anaphylaxis and/or protamine reactions were rare in this patient population in the perioperative environment. Based on these findings, this study does not recommend avoiding protamine solely based on a history of fish allergy when heparin reversal is required during surgery.

Deep Parasternal Intercostal Plane Block for Postoperative Analgesia After Sternotomy for Cardiac Surgery-A Retrospective Cohort Study.

OBJECTIVE: To examine the analgesic efficacy of postoperative deep parasternal intercostal plane (DPIP) blocks for patients having cardiac surgery via median sternotomy. DESIGN: This single-center retrospective study compared patients receiving bilateral DPIP blocks with a matched cohort of patients not receiving DPIP blocks. SETTING: Large quaternary referral center. PARTICIPANTS: Adult patients admitted to the authors' institution from January 1, 2016, to August 14, 2020, for elective cardiac surgery via median sternotomy. INTERVENTIONS: Patients received ultrasound-guided bilateral DPIP blocks. MEASUREMENTS AND MAIN RESULTS: A total of 113 patients received a DPIP block; 3,461 patients did not. The estimated multiplicative change in cumulative opioid consumption through 24 hours was 0.42 (95% CI 0.32-0.56; p < 0.001), indicating that patients receiving DPIP blocks required 60% fewer opioids than patients who did not. Proportional odds ratios for the average pain score on postoperative day (POD) 0 was 0.46 (95% CI 0.32-0.65; p < 0.001), and POD 1 was 0.67 (95% CI 0.47-0.94; p = 0.021), indicating lower pain scores for patients receiving blocks. The exploratory analysis identified an inverse correlation between DPIP blocks and atrial fibrillation incidence (2% v 15%; inverse probability of treatment weighting odds ratio 0.088, 95% CI 0.02-0.41; p = 0.002). CONCLUSIONS: The use of DPIP blocks in patients undergoing cardiac surgery via median sternotomy was associated with less opioid use and improved pain scores in the early postoperative period compared with patients not receiving blocks. Prospective randomized controlled studies should further elucidate the efficacy and risks of DPIP blocks in cardiac surgery.

Does type of bone graft matter? A retrospective review of the use of biological bone grafts in patients undergoing elective 1-3 level spinal interbody fusion.

OBJECTIVE: There is a lack of strong evidence for use of expensive bone substitutes. This study compares perioperative data and patient reported quality-of-life outcomes across the varied types of bone graft extenders. The study analyzes the existing Quality and Outcomes Database and evaluates patient reported outcomes for 1-3 level lumbar fusion procedures comparing across different types of biologics bone graft. METHODS: We retrospectively analyzed a prospectively collected data registry. Bone graft implant data were collected and grouped into the following categories: (1) Autograft with basic allograft (2) Enhanced, synthetic, or cellular allograft (3) Use of BMP. Preoperative and 1 year patient reported outcomes and perioperative data from the prospective collected registry were analyzed. RESULTS: There were 384 patients included in this study. There were 168 (43.8%) patients in group 1, 133 (34.6%) patients in group 2, and 83 (21.6%) in group 3. There were no group differences in baseline or 1 year back pain, leg pain, ODI, or EQ-5D. The GLM Repeated Measures results indicate a significant difference within each of the three groups between the preoperative and postoperative measures for back pain, leg pain, ODI, and EQ-5D. The change over time was not significantly different between the groups. CONCLUSIONS: Bone graft extenders are a significant contributor to the cost of lumbar fusion. This study demonstrates no difference in preoperative, and 1 year patient reported outcomes between the three groups. There was no significant difference in rate of reoperations across the three groups.

Perceptions of Wild Pig Impact, Management, and Policy in Alabama.

Successful management of invasive species often requires working across public and private landownerships. A prime example of an invasive species that commonly occurs on privately and publicly owned and managed lands is the wild pig (Sus scrofa). Because of the multitude of negative impacts associated with wild pigs, management must occur across both private and public lands to achieve widespread control and sustained success. However, managing wild pigs across property boundaries is challenging as we know very little about differing management practices and landowner perspectives. To address this knowledge gap, we sought to understand wild pig management efforts on privately owned lands, the perceived economic, ecological, and human health impact of wild pigs, and beliefs related to policy. Generally, stakeholders believe wild pigs have negative impacts on wildlife, the economy, and ecological and public health, however less than half of landowners participate in wild pig control. Furthermore, stakeholders believe that the responsibility of managing and paying for damages associated with wild pigs lies with individual landowners. Our findings suggest that increased efficacy of wild pig control and collaboration between private and public landowners is not only possible but also necessary if wild pig population control is to be regionally successful.

Embracing Robotics in Microsurgery: Robotic-Assisted Deep Inferior Epigastric Perforator Flap Breast Reconstruction.

The integration of robotic-assisted surgery (RAS) has transformed various surgical disciplines, including more recently plastic surgery. While RAS has gained acceptance in multiple specialties, its integration in plastic surgery has been gradual, challenging traditional open methods. Robotic-assisted deep inferior epigastric perforator (DIEP) flap breast reconstruction is a technique aimed at overcoming drawbacks associated with the traditional open DIEP flap approach. These limitations include a relatively large fascial incision length, potentially increasing rates of postoperative pain, abdominal bulge, hernia rates, and core weakening. The robotic-assisted DIEP flap technique emerges as an innovative and advantageous approach in fascial-sparing abdominal autologous breast reconstruction. While acknowledging certain challenges such as increased operative time, ongoing refinements are expected to further improve the overall surgical experience, optimize results, and solidify the role of robotics in advancing reconstructive microsurgical procedures in plastic surgery. Herein, the authors provide an overview of robotic surgery in the context of plastic surgery and its role in the DIEP flap harvest for breast reconstruction.

Flux Crystal Growth of the Extended Structure Pu(V) Borate Na2(PuO2)(BO3).

As part of our exploration of plutonium-containing materials as potential nuclear waste forms, we report the first extended structure Pu(V) material and the first Pu(V) borate. Crystals of Na2(PuO2)(BO3) were grown out of mixed hydroxide/boric acid flux and found to crystallize in the orthorhombic space group Cmcm with lattice parameters of a = 9.9067(4) Å, b = 6.5909(2) Å, and c = 6.9724(2) Å. Na2(PuO2)(BO3) adopts a layered structure in which layers of PuO2(BO3)2- are separated by sodium cations. Plutonium is found in a pentagonal bipyramidal coordination environment, with axial Pu(V)-O plutonyl bond lengths of 1.876(3) Å and equatorial Pu-O bond lengths ranging from 2.325(5) to 2.467(3) Å. We find that the Pu(V)-O plutonyl bond lengths are approximately 0.1 Å longer than the reported Pu(VI)-O plutonyl bond lengths and shorter by approximately 0.033 Å than the corresponding U(V) uranyl bond lengths. Raman spectroscopy on single crystals was used to determine the PuO2+ plutonyl stretching and the equatorial breathing mode frequencies of the pentagonal bipyramidal coordination environment around plutonium. Density functional theory calculations were used to calculate the Raman spectrum to help identify the Raman bands at 690 and 630 cm-1 as corresponding to the plutonyl(V) ν1 stretch and the equatorial PuO5 breathing mode, respectively. UV-vis measurements on single crystals indicate semiconducting behavior with a band gap of ∼2.60 eV.

Sequencing of Camelina neglecta, a diploid progenitor of the hexaploid oilseed Camelina sativa.

Camelina neglecta is a diploid species from the genus Camelina, which includes the versatile oilseed Camelina sativa. These species are closely related to Arabidopsis thaliana and the economically important Brassica crop species, making this genus a useful platform to dissect traits of agronomic importance while providing a tool to study the evolution of polyploids. A highly contiguous chromosome-level genome sequence of C. neglecta with an N50 size of 29.1 Mb was generated utilizing Pacific Biosciences (PacBio, Menlo Park, CA) long-read sequencing followed by chromosome conformation phasing. Comparison of the genome with that of C. sativa shows remarkable coincidence with subgenome 1 of the hexaploid, with only one major chromosomal rearrangement separating the two. Synonymous substitution rate analysis of the predicted 34 061 genes suggested subgenome 1 of C. sativa directly descended from C. neglecta around 1.2 mya. Higher functional divergence of genes in the hexaploid as evidenced by the greater number of unique orthogroups, and differential composition of resistant gene analogs, might suggest an immediate adaptation strategy after genome merger. The absence of genome bias in gene fractionation among the subgenomes of C. sativa in comparison with C. neglecta, and the complete lack of fractionation of meiosis-specific genes attests to the neopolyploid status of C. sativa. The assembled genome will provide a tool to further study genome evolution processes in the Camelina genus and potentially allow for the identification and exploitation of novel variation for Camelina crop improvement.