Identification and functional analysis of a chromosome 2D fragment harboring TaFPF1 gene with the potential for yield improvement using a late heading wheat mutant.

KEY MESSAGE: A chromosome fragment influencing wheat heading and grain size was identified using mapping of m406 mutant. The study of TaFPF1 in this fragment provides more insights into wheat yield improvement. In recent years, wheat production has faced formidable challenges driven by rapid population growth and climate change, emphasizing the importance of improving specific agronomic traits such as heading date, spike length, and grain size. To identify potential genes for improving these traits, we screened a wheat EMS mutant library and identified a mutant, designated m406, which exhibited a significantly delayed heading date compared to the wild-type. Intriguingly, the mutant also displayed significantly longer spike and larger grain size. Genetic analysis revealed that a single recessive gene was responsible for the delayed heading. Surprisingly, a large 46.58 Mb deletion at the terminal region of chromosome arm 2DS in the mutant was identified through fine mapping and fluorescence in situ hybridization. Thus, the phenotypes of the mutant m406 are controlled by a group of linked genes. This deletion encompassed 917 annotated high-confidence genes, including the previously studied wheat genes Ppd1 and TaDA1, which could affect heading date and grain size. Multiple genes in this region probably contribute to the phenotypes of m406. We further investigated the function of TaFPF1 using gene editing. TaFPF1 knockout mutants showed delayed heading and increased grain size. Moreover, we identified the direct upstream gene of TaFPF1 and investigated its relationship with other important flowering genes. Our study not only identified more genes affecting heading and grain development within this deleted region but also highlighted the potential of combining these genes for improvement of wheat traits.

The involvement of circulating miR-146a and miR-27a in patients with atherosclerotic cardiovascular disease after SARS-CoV-2 infection.

BACKGROUND: Atherosclerotic cardiovascular disease (ASCVD) is a group of clinical diseases based on pathology of atherosclerosis that is the leading cause of mortality worldwide. There is a bidirectional interaction between ASCVD and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Alterations in circulating miRNAs levels are involved in the development of ASCVD in patients infected with SARS-CoV-2, however, the correlation between ASCVD co-infection with SARS-CoV-2 and alterations of cardiac-specific miRNAs is not well understood. HYPOTHESIS: The circulating miR-146a and miR-27a are involved in bidirectional interactions between ASCVD and SARS-CoV-2 infections. METHODS: Circulating miR-146a and miR-27a levels were measured in serum and PBMCs deriving from ASCVD patients and controls after SARS-CoV-2 infection by qRT-PCR analysis. The levels of neutralizing antibodies-resistant SARS-CoV-2 in human serum was determined by competitive magnetic particle chemiluminescence method. Interleukin (IL)-6 levels were detected by automatic biochemical analyzer using electrochemiluminescence. RESULTS: Significant downregulation of circulating miR-146a and upregulation of miR-27a in ASCVD patients after infection with SARS-CoV-2 compared with controls were observed, among which the alterations were more evident in ASCVD patients comorbid with hyperlipidemia and diabetes mellitus. Consistently, correlation analysis revealed that serum miR-146a and miR-27a levels were associated with the levels of lipids and glucose, inflammatory response, and immune function in ASCVD patients. Remarkably, SARS-CoV-2 S protein RBD stimulation of PBMCs derived from both ASCVD and controls significantly downregulated miR-146a, upregulated miR-27a expression levels, and promoted IL-6 release in vitro. CONCLUSIONS: The circulating miR-146a and miR-27a are involved in metabolism, inflammation, and immune levels in patients with ASCVD after SARS-CoV-2 infection, laying the foundation for the development of strategies to prevent the risk of SARS-CoV-2 infection in ASCVD patients.