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The establishment of symbiosis between legume and rhizobium results in the formation of nodule. Phytocyanins (PCs) are a class of plant-specific blue copper proteins, playing critical roles in plant development including nodule formation. Although a few PC genes have been isolated from nodules, their functions are still unclear. Here, we performed a genome-wide identification of PC family in seven sequenced legume species (Medicago truncatula, Glycine max, Cicer arietinum, Cajanus cajan, Lotus japonicus, Vigna angularis and Phaseolus vulgaris) and found PCs experienced a remarkable expansion in M. truncatula and G. max. Further, we conducted an in-depth analysis of PC family in the model legume M. truncatula. Briefly, 82 MtPCs were divided into four subfamilies and clustered into seven clades, with a large proportion of tandem duplications and various cross-tissues expression patterns. Importantly, some PC s, such as MtPLC1, MtENODL27 and MtENODL28 were preferentially expressed in nodules. Further, RNA interference (RNAi) experiment revealed the knockdown of MtENDOL27 and MtENDOL28 impaired rhizobia infection, nodule numbers and nitrogenase activity. Moreover, in the MtENODL27 -RNAi nodules, the infected cells were reduced and the symbiosomes did not reach the elongated stage, indicating MtENDOL27 is required for rhizobia infection and nodule development. In addition, co-expression analysis showed MtPLC1, MtENODL27 and MtENODL28 were grouped into two different functional modules and co-expressed with the known symbiotic nitrogen fixation-related genes, suggesting that they might participate in nodulation via different ways. In summary, this study provides a useful resource for future researches on the structure and function of PC s in nodulation. [ABSTRACT FROM AUTHOR]

A six-axis force sensor with parallel 8/4-4 structure is introduced and its measurement principle is analyzed. Based on condition numbers of Jacobian matrix spectral norm of the sensor, the relationship between the force and moment isotropy and some structural parameters is deduced. Orthogonal test methods are used to determine the degree of primary and secondary factors that have significant effect on sensor characteristics. Furthermore, the relationship between each performance index and the structural parameters of the sensor is analyzed by the method of the atlas, which lays a foundation for structural optimization design of the force sensor. [ABSTRACT FROM AUTHOR]

Low-temperature (LT) is one of the major abiotic stresses that restrict the growth and development of maize seedlings. Brassinolides (BRs) have been shown to enhance LT tolerance in several plant species; the physiological and molecular mechanisms by which BRs enhance maize tolerance are still unclear. Here, we characterized changes in the physiology and transcriptome of N192 and Ji853 seedlings at the three-leaf stage with or without 2 μM 2,4-epibrassinolide (EBR) application at 25 and 15 °C environments via high-performance liquid chromatography and RNA-Sequencing. Physiological analyses revealed that EBR increased the antioxidant enzyme activities, enhanced the cell membrane stability, decreased the malondialdehyde formation, and inhibited the reactive oxygen species (ROS) accumulation in maize seedlings under 15 °C stress; meanwhile, EBR also maintained hormone balance by increasing indole-3-acetic acid and gibberellin 3 contents and decreasing the abscisic acid level under stress. Transcriptome analysis revealed 332 differentially expressed genes (DEGs) enriched in ROS homeostasis, plant hormone signal transduction, and the mitogen-activated protein kinase (MAPK) cascade. These DEGs exhibited synergistic and antagonistic interactions, forming a complex LT tolerance network in maize. Additionally, weighted gene co-expression network analysis (WGCNA) revealed that 109 hub genes involved in LT stress regulation pathways were discovered from the four modules with the highest correlation with target traits. In conclusion, our findings provide new insights into the molecular mechanisms of exogenous BRs in enhancing LT tolerance of maize at the seedling stage, thus opening up possibilities for a breeding program of maize tolerance to LT stress. [ABSTRACT FROM AUTHOR]

Aims: End-stage hypertrophic cardiomyopathy (ES-HCM) is a disease with severe complications and a poor prognosis. This study aimed to explore the influencing and prognostic factors of ES-HCM., Methods and Results: A total of 1282 patients with HCM who were hospitalized for the first time at Fujian Medical University Union Hospital between 1 January 2013 and 30 September 2021 were recorded. The patients with HCM and left ventricular ejection fraction (LVEF) < 50% were defined as having ES-HCM, and a control group (LVEF ≥ 50%) was generated from the collected medical records of HCM. The patients were matched in a ratio of 4:1 based on age and sex. Logistic regression analysis was used to determine the influencing factors of ES-HCM. Kaplan-Meier survival analysis was performed to analyse the clinical outcomes of ES-HCM patients. A total of 250 inpatients with HCM were enrolled in the study; 50 patients had ES-HCM, and 200 had HCM with LVEF ≥ 50%. The mean age of the patients at enrolment was 62.5 ± 10.3 years, and 215 patients (215/250, 86.0%) were male. The median follow-up time of the patients was 2.8 (1.4-5.4) years. The incidence of all-cause death and cardiovascular death in patients with ES-HCM was higher than those in patients with HCM and LVEF ≥ 50% (22/50 [44.0%] vs. 13/200 [6.5%]; 12/50 [24.0%] vs. 4/200 [2.0%], all P < 0.001). Multivariate logistic regression analysis showed that the influencing factors associated with ES-HCM included age at first symptom onset (odds ratio [OR] = 0.95, 95% CI [0.90, 1.00], P = 0.042), New York Heart Association (NYHA) class (OR = 7.73, 95% CI [2.93, 20.41], P < 0.001), heart rate (OR = 1.07, 95% CI [1.02, 1.12], P = 0.003), QRS duration (OR = 1.03, 95% CI [1.00, 1.05], P = 0.020), left ventricular end-diastolic diameter (LVEDD) (OR = 1.15, 95% CI [1.04, 1.28], P = 0.006), left atrial anteroposterior diameter (LAD) (OR = 1.13, 95% CI [1.03, 1.24], P = 0.012), and maximum left ventricular wall thickness (MLVWT) (OR = 0.80, 95% CI [0.68, 0.93], P = 0.005). Among the 50 patients with ES-HCM, NYHA class (P < 0.001) and heart rate (P = 0.017) were each associated with a higher likelihood and earlier occurrence of heart transplantation or all-cause mortality in univariate analyses., Conclusions: The influencing factors for ES-HCM included the age at first symptom onset, NYHA class, heart rate, QRS duration, LVEDD, LAD, and MLVWT. Both NYHA class and heart rate were related to the prognosis of ES-HCM., (© 2024 The Author(s). ESC Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology.)