A KNOX â ¡ transcription factor suppresses the NLR immune receptor BRG8-mediated immunity in rice.

Nucleotide-binding site and leucine-rich repeat (NLR) proteins are activated by detecting pathogen effectors, which in turn trigger host defenses and cell death. Although many NLRs have been identified, the mechanisms responsible for NLR-triggered defense responses are still poorly understood. In this study, through a genome-wide association study approach, we identified a novel NLR gene, Blast Resistance Gene 8 (BRG8), which confers resistance to rice blast and bacterial blight diseases. BRG8 overexpression and complementation lines exhibit enhanced resistance to both pathogens. Subcellular localization assays showed that BRG8 is localized in both the cytoplasm and the nucleus. Additional evidence revealed that nuclear-localized BRG8 can enhance rice immunity without a hypersensitive response (HR)-like phenotype. We also demonstrated that the coiled-coil domain of BRG8 not only physically interacts with itself but also interacts with the KNOX Ⅱ protein HOMEOBOX ORYZA SATIVA59 (HOS59). Knockout mutants of HOS59 in the BRG8 background show enhanced resistance to Magnaporthe oryzae strain CH171 and Xoo strain CR4, similar to that of the BRG8 background. By contrast, overexpression of HOS59 in the BRG8 background will compromise the HR-like phenotype and resistance response. Further analysis revealed that HOS59 promotes the degradation of BRG8 via the 26S proteasome pathway. Collectively, our study highlights HOS59 as an NLR immune regulator that fine-tunes BRG8-mediated immune responses against pathogens, providing new insights into NLR associations and functions in plant immunity.

OsCOL5 suppresses heading through modulation of Ghd7 and Ehd2, enhancing rice yield.

KEY MESSAGE: OsCOL5, an ortholog of Arabidopsis COL5, is involved in photoperiodic flowering and enhances rice yield through modulation of Ghd7 and Ehd2 and interactions with OsELF3-1 and OsELF3-2. Heading date, also known as flowering time, plays a crucial role in determining the adaptability and yield potential of rice (Oryza sativa L.). CONSTANS (CO)-like is one of the most critical flowering-associated gene families, members of which are evolutionarily conserved. Here, we report the molecular functional characterization of OsCOL5, an ortholog of Arabidopsis COL5, which is involved in photoperiodic flowering and influences rice yield. Structural analysis revealed that OsCOL5 is a typical member of CO-like family, containing two B-box domains and one CCT domain. Rice plants overexpressing OsCOL5 showed delayed heading and increases in plant height, main spike number, total grain number per plant, and yield per plant under both long-day (LD) and short-day (SD) conditions. Gene expression analysis indicated that OsCOL5 was primarily expressed in the leaves and stems with a diurnal rhythm expression pattern. RT-qPCR analysis of heading date genes showed that OsCOL5 suppressed flowering by up-regulating Ghd7 and down-regulating Ehd2, consequently reducing the expression of Ehd1, Hd3a, RFT1, OsMADS14, and OsMADS15. Yeast two-hybrid experiments showed direct interactions of OsCOL5 with OsELF3-1 and OsELF3-2. Further verification showed specific interactions between the zinc finger/B-box domain of OsCOL5 and the middle region of OsELF3-1 and OsELF3-2. Yeast one-hybrid assays revealed that OsCOL5 may bind to the CCACA motif. The results suggest that OsCOL5 functions as a floral repressor, playing a vital role in rice's photoperiodic flowering regulation. This gene shows potential in breeding programs aimed at improving rice yield by influencing the timing of flowering, which directly impacts crop productivity.

The clock component OsLUX regulates rice heading through recruiting OsELF3-1 and OsELF4s to repress Hd1 and Ghd7.

INTRODUCTION: Circadian clocks coordinate internal physiology and external environmental factors to regulate cereals flowering, which is critical for reproductive growth and optimal yield determination. OBJECTIVES: In this study, we aimed to confirm the role of OsLUX in flowering time regulation in rice. Further research illustrates how the OsELF4s-OsELF3-1-OsLUX complex directly regulates flowering-related genes to mediate rice heading. METHODS: We identified a circadian gene OsLUX by the MutMap method. The transcription levels of flowering-related genes were evaluated in WT and oslux mutants. OsLUX forms OsEC (OsELF4s-OsELF3-1-OsLUX) complex were supported by yeast two-hybrid, pull down, BiFC, and luciferase complementation assays (LCA). The EMSA, Chip-qPCR, luciferase luminescence images, and relative LUC activity assays were performed to examine the targeted regulation of flowering genes by the OsEC (OsELF4s-OsELF3-1-OsLUX) complex. RESULTS: The circadian gene OsLUX encodes an MYB family transcription factor that functions as a vital circadian clock regulator and controls rice heading. Defect in OsLUX causes an extremely late heading phenotype under natural long-day and short-day conditions, and the function was further confirmed through genetic complementation, overexpression, and CRISPR/Cas9 knockout. OsLUX forms the OsEC (OsELF4s-OsELF3-1-OsLUX) complex by recruiting OsELF3-1 and OsELF4s, which were required to regulate rice heading. OsELF3-1 contributes to the translocation of OsLUX to the nucleus, and a compromised flowering phenotype results upon mutation of any component of the OsEC complex. The OsEC complex directly represses Hd1 and Ghd7 expression via binding to their promoter's LBS (LUX binding site) element. CONCLUSION: Our findings show that the circadian gene OsLUX regulates rice heading by directly regulating rhythm oscillation and core flowering-time-related genes. We uncovered a mechanism by which the OsEC target suppresses the expression of Hd1 and Ghd7 directly to modulate photoperiodic flowering in rice. The OsEC (OsELF4s-OsELF3-1-OsLUX)-Hd1/Ghd7 regulatory module provides the genetic targets for crop improvement.

The outcome of isolated calf muscle vein thrombosis after open reduction and internal fixation for closed intra-articular distal femur fractures: a prospective cohort study.

BACKGROUND: To observe the outcome of isolated calf muscle vein thrombosis (ICMVT) undergoing open reduction and internal fixation (ORIF) for closed intra-articular distal femur fractures (DFFs) and to analyze related factors. METHODS: The study was designed as a prospective clinical cohort study at our hospital. From August 2018 to August 2020,a total of 140 patients with flesh ICMVT after ORIF for closed intra-articular DFFs were collected during hospitalization. After the administration of antithrombotic agents immediately after diagnosis, the location and prognosis of postoperative ICMVT were examined by Duplex ultrasonography (DUS) with a three-month follow-up. There were 29 males and 111 females with the average age of 70.16 ± 8.75 years old. Sonography was used to evaluate the resolution of muscular vein thrombosis at the time point of the third month postoperatively and the results were compared between the two time points. Multivariable analysis was performed to evaluate the relationship between the resolution of ICMVT three months postoperatively and risk factors including age, Body Mass Index (BMI), gender, thrombosis length (> 5 / ≤5 cm), thrombosis diameter(> 0.6/≤0.6 cm), and thrombosis-related biochemistry indices. RESULTS: The postoperative ICMVTs was diagnosed at 5.47 ± 2.46 days after ORIF for closed intra-articular DFFs. At the follow up of 3 months,120 cases was tending to disappear with 88 cases(62.9 %) completely dissolved and 32 cases(22.9 %) partly dissolved. There existed 14 cases (10.0 %) without change on the size and 6 cases (4.2 %) with proximal propagation. Multivariate analysis revealed that thrombus diameter over 0.6 cm (odds ratio [OR], 8.900; 95 % confidence interval [CI]: 3.623-21.865), thrombus length over 5.0 cm (OR, 3.904; 95 % CI, 1.121-13.603), FIB over 3.0 g/L (OR, 3.627; 95 % CI, 1.356-9.689), and D-dimer over 1.0 mg/L (OR, 2.602; 95 % CI, 1.075-6.296) were four independent risk factors of non-completely dissolved ICMVTs. CONCLUSIONS: 85.8 % of ICMVT was tending to disappear at the third months after ORIF for closed intra-articular DFFs. Thrombus diameter, thrombus length, FIB, and D-dimer were four independent risk factors of non-completely dissolved ICMVTs. The Thrombus diameter has a significant effect on the natural course of ICMVTs, especially with diameter larger than 0.6 cm.

Colon cancer data analysis by chameleon algorithm.

Detecting the key differential genes of colon cancers is very important to tell colon cancer patients from normal people. A gene selection algorithm for colon cancers is proposed by using the dynamic modeling properties of chameleon algorithm and its capability to discover any arbitrary shape clusters. This chameleon algorithm based gene selection algorithm comprises three steps. The first step is to select those genes with higher Fisher function values as candidate genes. The second step is to detect gene groups by using chameleon algorithm based on Euclidean distance. The third step is to select the most important gene from each gene cluster to comprise the gene subset by using the information index to classification of each gene. After that the chameleon algorithm is used to detect groups of colon cancer patients and normal people only with genes in gene subset. The final clustering accuracy of chameleon algorithm with the selected genes is up to 85.48%. The clustering analysis to colon cancer data and the comparisons to the other related studies demonstrate that the proposed algorithm is effective in detecting the differential genes of colon cancers.

SPECT and near-infrared fluorescence imaging of breast cancer with a neuropilin-1-targeting peptide.

Breast cancer is the most common malignant cancer and is the leading cause of cancer death among females. Molecular imaging is a promising approach for the early detection and staging of breast cancer as well as for assessing therapeutic responses. Tumor-targeting peptides are effective targeting vehicles for molecular imaging. Here, we identified a breast cancer-targeting peptide CLKADKAKC (CK3) contains a cryptic C-end rule motif that may mediate its binding to neuropilin-1 (NRP-1), an attractive therapeutic target which expression was associated with poor outcome of the patients with breast cancer. Phage CK3 bound to NRP-1-positive breast cancer cells, which could be inhibited by peptide CK3 in a dose-dependent manner or by knock-down NRP-1 expression. Consistently, NRP-1 overexpression in cells increased the binding of phage CK3. Furthermore, peptide CK3 co-localized with NRP-1. Importantly, unlike previously reported NRP-1-targeting peptides with exposed C-end rule motifs, peptide CK3 did not penetrate into lungs and heart in vivo, which could make it more clinically applicable. Single-photon emission CT (SPECT) and near-infrared fluorescence (NIRF) imaging showed enrichment of peptide CK3 to the xenograft tumors in nude mice. In conclusion, as a novel NRP-1-targeting peptide, peptide CK3 could be used for breast cancer molecular imaging, which may represent a new avenue for breast cancer diagnostics, staging and assessments of therapeutic response.

Technetium-99m(V)-dimercaptosuccinic acid osteotropism in Staphylococcus aureus-induced arthritis regulated by glucose-mediated acidification.

OBJECTIVES: To study the possible mechanism of the technetium-99m complex of dimercaptosuccinic acid 99mTc(V)-DMSA accumulation in a model of Staphylococcus aureus-induced bacterial arthritis regulated by glucose. MATERIALS AND METHODS: After making the S. aureus-induced bacterial arthritis model, 14 rabbits were divided into two groups randomly, with one group receiving 6 g/kg 30% glucose administration. Then all the rabbits were injected with 74 MBq 99mTc(V)-DMSA. Whole-body single photon emission computed tomography was applied at different time points. The change of blood pH after blood glucose was also assayed. The percentage of residual activity was evaluated over time in multiple regions of interest, including the inflammatory joint lesions and the contralateral normal joints. Regional joint tissue pH was measured with a needle probe at different times after injecting glucose solution. Forty-two rabbits were divided into six groups to assay the percentage injected dose. RESULTS: 99mTc(V)-DMSA showed a noticeable osteotropic character in bone pathologies. There was no influence of biodistribution of 99mTc(V)-DMSA by glucose loading, but the glucose loading remarkably increased the uptake levels of 99mTc(V)-DMSA in inflammatory joint lesions. A peak difference in glucose-loaded lesion/normal uptake was observed after 6 h. The pH values of the inflammatory joints were noticeably lower than those of the normal joints of the contralateral legs. CONCLUSION: The increased lesion uptake and tissue acidification in the glucose-loaded group supports the hypothesis that glucose acidosis increases DMSA uptake in bacterial arthritis, as has been observed in tumors.

A novel role of minocycline: attenuating morphine antinociceptive tolerance by inhibition of p38 MAPK in the activated spinal microglia.

We have previously demonstrated that activation of p38 mitogen-activated protein kinase (p38 MAPK) in the spinal microglia mediates morphine antinociceptive tolerance. Minocycline, a selective inhibitor of microglia activation, has been reported to attenuate peripheral inflammation-induced hyperalgesia by depressing p38 MAPK in the spinal microglia. The aim of the present study is to explore the effect of intrathecal minocycline on the development of morphine antinociceptive tolerance and p38 activation in the spinal microglia induced by chronic morphine treatment. Minocycline (20, 50 and 100 microg) was given intrathecally 30 min before each morphine (15 microg) administration for consecutive 7 days. It was shown that minocycline attenuated tolerance to morphine analgesia in a dose-dependent manner. Minocycline administration (50 microg) which was initiated on day 4 followed by another 4 days administration partially reversed the established morphine antinociceptive tolerance. However, minocycline treatment which was started on day 8 followed by its administration for 4 more days failed to reverse the established morphine tolerance. Immunohistochemical analysis showed that chronic intrathecal morphine-induced activation of p38 MAPK in the spinal microglia. Minocycline at a dose that was shown to antagonize tolerance to morphine analgesia significantly inhibited the increase in p38 MAPK activation in the spinal microglia. To our knowledge, this is the first study to demonstrate that minocycline antagonizes morphine antinociceptive tolerance, possibly due to the inhibition of p38 activation in the spinal microglia.