Cloning and Bioinformatics Analysis of <i>Rosa rugose S</i>Locus F-Box Gene (<i>RrSLF</i>)

In order to reveal the phenomenon of R. rugose pollination incompatibility, the full-length cDNA sequence of S Locus F-box Gene was cloned for the first time from the pollen of Rosa rugose “Zilong wochi” with RT-PCR and RACE methods and named as RrSLF. The full-length cDNA is 1236 bp with an open reading frame of 1122 bp, encoding 343 amino acids. The derived protein has a molecular weight of 43.7 kD, a calculated pI of 6.24, an F-box conserved domain at position 343 - 741, and belongs to F-box family. The derived protein is a Hydrophobicity protein secreted into the cytoplasm. There is no transmembrane domain and no signal peptide cleavage site, twenty-one Ser phosphorylation sites, seven Thr phosphorylation sites, seven Tyr phosphorylation sites, two N-glycosylation sites, and no O-glycosylation sites. There are 22.25% α-helixes, 31.37% random coil, 32.17% extended peptide chain, and 14.21% β-corner structure. This protein and the SFB/SLF protein from Rosaceae Prunus fruit, including Prunus speciose, share a sequence homology of 59% - 61%;all of the proteins contain an F-box conserved domain, two hypervariable regions HVa, HVb, and two variable regions V1, V2. Furthermore, their phylogenetic relationships are consistent with their traditional classifications. These results were meaningful to reveal the molecular mechanism of Rosa rugose pollination incompatibility and improve the theory and techniques of breeding ornamental Rosa rugose.

A Study on the Aseptic Germination Method for <i>Rosa rugose</i>Seeds

In order to find a method to break dormancy of Rosa rugose seeds and interspecific hybrid seeds between Rosa rugose and Rosa hybrid quickly, and accelerate the breeding process of interspecific hybridization between Rosa rugose and Rosa hybrid, the influence of concentrated acid, seed maturity, GA3 (gibberellin) and low temperature (4°C) on seed germination of Rosa rugose from Muping was researched under aseptic condition. The results showed that aseptic germination can significantly shorten the germination time of Rosa rugose seeds and raise its germination ratio. Before inoculation, concentrated acid treatment greatly increased the germination rate and reduced the contamination rate of the seeds. The higher the degree of maturity of seeds is, the lower the germination rate would be, and the best time for seed to aseptic germination is 60 d after pollination. The addition of GA3 in 1/2MS medium could promote seeds germination better, and when the concentration of GA3 was 0.15 mg/L, the seed germination ratio was the highest;the germination time decreased and the seed germination ratio increased gradually as the treatment time at 4°C lasted longer.

Melatonin decreases GSDME mediated mesothelial cell pyroptosis and prevents peritoneal fibrosis and ultrafiltration failure

Peritoneal fibrosis together with increased capillaries is the primary cause of peritoneal dialysis failure.Mesothelial cell loss is an initiating event for peritoneal fibrosis.We find that the elevated glucose concentrations in peritoneal dialysate drive mesothelial cell pyroptosis in a manner dependent on caspase-3 and Gasdermin E,driving downstream inflammatory responses,including the activation of macrophages.Moreover,pyroptosis is associated with elevated vascular endothelial growth factor A and C,two key factors in vascular angiogenesis and lymphatic vessel formation.GSDME deficiency mice are protected from high glucose induced peritoneal fibrosis and ultrafiltration failure.Application of melatonin abrogates mesothelial cell pyroptosis through a MT1R-mediated action,and successfully reduces peritoneal fibrosis and angiogenesis in an animal model while preserving dialysis efficacy.Mechanistically,melatonin treatment maintains mitochondrial integrity in mesothelial cells,meanwhile activating m TOR signaling through an increase in the glycolysis product dihydroxyacetone phosphate.These effects together with quenching free radicals by melatonin help mesothelial cells maintain a relatively stable internal environment in the face of high-glucose stress.Thus,Melatonin treatment holds some promise in preserving mesothelium integrity and in decreasing angiogenesis to protect peritoneum function in patients undergoing peritoneal dialysis.