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Summary: Grain size and weight are important components of a suite of yield‐related traits in crops. Here, we showed that the CRISPR‐Cas9 gene editing of TaGW7, a homolog of rice OsGW7 encoding a TONNEAU1‐recruiting motif (TRM) protein, affects grain shape and weight in allohexaploid wheat. By editing the TaGW7 homoeologs in the B and D genomes, we showed that mutations in either of the two or both genomes increased the grain width and weight but reduced the grain length. The effect sizes of mutations in the TaGW7 gene homoeologs coincided with the relative levels of their expression in the B and D genomes. The effects of gene editing on grain morphology and weight traits were dosage dependent with the double‐copy mutant showing larger effect than the respective single copy mutants. The TaGW7‐centered gene co‐expression network indicated that this gene is involved in the pathways regulating cell division and organ growth, also confirmed by the cellular co‐localization of TaGW7 with α‐ and β‐tubulin proteins, the building blocks of microtubule arrays. The analyses of exome capture data in tetraploid domesticated and wild emmer, and hexaploid wheat revealed the loss of diversity around TaGW7‐associated with domestication selection, suggesting that TaGW7 is likely to play an important role in the evolution of yield component traits in wheat. Our study showed how integrating CRISPR‐Cas9 system with cross‐species comparison can help to uncover the function of a gene fixed in wheat for allelic variants targeted by domestication selection and select targets for engineering new gene variants for crop improvement. Significance Statement: Grain size and weight are important components of a suite of yield‐related traits in crops. We used CRISPR‐Cas9 gene editing, gene expression network and diversity analyses to demonstrate that TaGW7: (i) affects grain shape and weight in wheat through pathways regulating cell division and organ growth; (ii) was the target of domestication and improvement selection; and (iii) can be used as a target for CRISPR‐Cas9‐based mutagenesis to expand diversity available for crop improvement. [ABSTRACT FROM AUTHOR]

Plants have evolved a large number of transcription factors (TF), which are enriched among duplicate genes, highlighting their roles in complex regulatory networks. The APETALA2/EREBP-like genes constitute a large plant TF family and participate in development and stress responses. To probe the conservation and divergence of AP2/EREBP genes, we analyzed the duplication patterns of this family in Brassicaceae and identified interacting proteins of representative Arabidopsis AP2/EREBP proteins. We found that many AP2/EREBP duplicates generated early in Brassicaceae history were quickly lost, but many others were retained in all tested Brassicaceae species, suggesting early functional divergence followed by persistent conservation. In addition, the sequences of the AP2 domain and exon numbers were highly conserved in rosids. Furthermore, we used 16 A. thaliana AP2/EREBP proteins as baits in yeast screens and identified 1,970 potential AP2/EREBP-interacting proteins, with a small subset of interactions verified in planta. Many AP2 genes also exhibit reduced expression in an anther-defective mutant, providing a possible link to developmental regulation. The putative AP2-interacting proteins participate in many functions in development and stress responses, including photomorphogenesis, flower development, pathogenesis, drought and cold responses, abscisic acid and auxin signaling. Our results present the AP2/EREBP evolution patterns in Brassicaceae, and support a proposed interaction network of AP2/EREBP proteins and their putative interacting proteins for further study. [ABSTRACT FROM AUTHOR]

Background: Blood samples from 42 patients with coronavirus disease 2019 (COVID-19) with varying degrees of infection were examined to further explore the relationship between clinical features, immune factors and COVID-19, as well as the diagnostic and predictive values of clinical features and immune factors in severe disease progression., Methods: This study included 42 nucleic acid-positive COVID-19 patients admitted to the First Hospital of Jiaxing from January 26, 2020 to February 21, 2020, who were divided into mild-moderate group and severe group based on respiratory rate, resting oxygen saturation and alveolar oxygen partial pressure/O2 inhalation. On February 21, 2020, clinical data including sex, age, body mass index (BMI), past medical history, clinical symptoms, hematology indexes [white blood cell (WBC); neutrophil (NEUT); lymphocyte (LYM); C-reactive protein (CRP)] were collected. The chi-square test was used to compare the clinical data differences between the two groups, so as to perform comparative analysis in the context of serious disease development., Results: There were 8 cases of severe disease, and 34 cases of mild and moderate symptoms. Comparative analysis showed that patients with advanced age (≥60 years, OR =5.800, P=0.0286), history of hypertension (OR =5.800, P=0.0286) and pulmonary lobe lesions (≥4, OR =6.273, P=0.0270) were more likely to develop serious diseases. In addition, according to clinical symptoms, chest pain was more prominent in patients with severe disease. Laboratory tests showed that levels of WBC (severe 4.96±1.76 vs. mild-moderate 5.45±2.01, P=0.5300), NEUT (severe 3.56±1.44 vs. mild-moderate 3.94±1.87, P=0.5945) and LYM (severe 0.91±0.25 vs. mild-moderate 1.11±0.51, P=0.2903) were normal or decreased, but CRP level (severe 31.03±9.38 vs. mild-moderate 12.53±15.73, P=0.0029) was obviously increased, especially in patients with severe disease, with statistically significant difference between groups., Conclusions: Patients with hypertension and advanced age are more likely to develop deteriorate with COVID-19, and the number of lung lobes with lesions and chest pain may indicate disease progression. Notably, CRP level is significantly elevated in severe disease and it may be closely related to COVID-19 progression.