Mapping QTL conferring flag leaf senescence in durum wheat cultivars.

Flag leaf senescence is a critical factor affecting the yield and quality of wheat. The aim of this study was to identify QTLs associated with flag leaf senescence in an F10 recombinant inbred line population derived from durum wheats UC1113 and Kofa. Bulked segregant analysis using the wheat 660K SNP array identified 3225 SNPs between extreme-phenotype bulks, and the differential SNPs were mainly clustered on chromosomes 1A, 1B, 3B, 5A, 5B, and 7A. BSR-Seq indicated that the significant SNPs were mainly located in two intervals of 354.0-389.0 Mb and 8.0-15.0 Mb on 1B and 3B, respectively. Based on the distribution of significant SNPs on chromosomes 1B and 3B, a total of 109 insertion/deletion (InDel) markers were developed, and 8 of them were finally used to map QTL in UC1113/Kofa population for flag leaf senescence. Inclusive composite interval mapping identified two major QTL in marker intervals Mar2005-Mar2116 and Mar207-Mar289, explaining 14.2-15.4% and 31.4-68.6% of the phenotypic variances across environments, respectively. Using BSR-Seq, gene expression and sequence analysis, the TraesCS1B02G211600 and TraesCS3B02G023000 were identified as candidate senescence-associated genes. This study has potential to be used in cloning key genes for flag leaf senescence and provides available molecular markers for genotyping and marker-assisted selection breeding. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01410-3.

Mapping of quantitative trait loci for leaf rust resistance in the wheat population 'Xinmai 26/Zhoumai 22'.

Leaf rust, caused by the fungal pathogen Puccinia triticina (Pt), is one of the major and dangerous diseases of wheat, and has caused serious yield loss of wheat worldwide. Here, we investigated adult-plant resistance (APR) to leaf rust in a recombinant inbred line (RIL) population derived from 'Xinmai 26' and 'Zhoumai 22' over 3 years. Linkage mapping for APR to leaf rust revealed four quantitative trait loci (QTL) in this RIL population. Two QTL, QLr.hnau-2BS and QLr.hnau-3BS were contributed by 'Zhoumai22', whereas QLr.hnau-2DS and QLr.hnau-5AL were contributed by 'Xinmai 26'. The QLr.hnau-2BS covering a race-specific resistance gene Lr13 showed the most stable APR to leaf rust. Overexpression of Lr13 significantly increased APR to leaf rust. Interestingly, we found that a CNL(coiled coil-nucleotide-binding site-leucine-rich repeat)-like gene, TaCN, in QLr.hnau-2BS completely co-segregated with leaf rust resistance. The resistant haplotype TaCN-R possessed half the sequence of the coiled-coil domain of TaCN protein. Lr13 strongly interacted with TaCN-R, but did not interact with the full-length TaCN (TaCN-S). In addition, TaCN-R was significantly induced after Pt inoculation and changed the sub-cellular localization of Lr13 after interaction. Therefore, we hypothesized that TaCN-R mediated leaf rust resistance possibly by interacting with Lr13. This study provides important QTL for APR to leaf rust, and new insights into understanding how a CNL gene modulates disease resistance in common wheat.

[Research on the signal pathway of hydrogen sulfide regulating autophagy to protect intestinal injury in sepsis].

Sepsis is one of the main causes of death in critically ill patients. The intestinal tract is not only the organ easily involved in sepsis, but also the initial organ in the progression of sepsis, so the improvement of intestinal barrier function is the key of the treatment of sepsis. In recent years, it has been found that autophagy is involved in the pathological process of sepsis, maintaining mitochondrial function by clearing damaged organelles, inhibiting inflammation, oxidative stress and apoptosis, regulating immunity, maintaining intestinal homeostasis, and improving the condition and prognosis of sepsis. It is an effective target for the treatment of sepsis. As a new type of medical gas signal molecule, hydrogen sulfide (H2S) can regulate autophagy by regulating multiple signal pathways, which has become a new target in the treatment of sepsis. This article reviews the signal pathway regulation mechanism of H2S regulating autophagy in septic intestinal dysfunction.

[Role of hydrogen sulfide mediated autophagy related genes in intestinal function injury of sepsis].

OBJECTIVE: Sepsis is an organ dysfunction that endangers a patient's life caused by an imbalanced infection response, and is a clinically critical illness. Despite a deep understanding of the pathogenesis of sepsis, there has been no significant improvement in sepsis mortality during clinical treatment at home and abroad. In recent years, the role of autophagy in the pathogenesis of sepsis has become a new research point in the field of medical research. Autophagy may protect the body by removing pathogenic microorganisms, neutralizing microbial toxins, and regulating cytokine release in sepsis. Studies have shown that autophagy plays a role in heart and lung organ dysfunction and inflammatory immune response in sepsis. Studies have also shown that hydrogen sulphide (H2S) can activate autophagy through multiple signaling pathways, such as adenylate-activated protein kinase/mammalian target of rapamycin (AMPK/mTOR), phosphoinositide 3 kinase/Akt/mTOR (PI3K/Akt/mTOR), liver kinase B1/STE20 related adapter protein/mouse protein 25 (LKB1/STRAD/MO25) and microRNA-30c (miR-30c), etc. signaling pathways. This article reviewed the effects of H2S on autophagy-related genes Beclin-1 and microtubule-associated protein light 3 chain (LC3) on intestinal function of sepsis in order to explore the H2S-mediated autophagy gene expression in pus. The protective role of autophagy gene for intestinal dysfunction provides a new strategy for the treatment of sepsis in the future.