Cloning and Expression Analysis of <i>RrMYB</i>113 Gene Related to Anthocyanin Biosynthesis in <i>Rosa rugose</i>

Anthocyanin is one of water-soluble natural pigments widely existing in flowers, fruits, stems, leaves and seeds of plants, and it is the major factor conferring pink or red to the petals of Rosa rugose. MYB TFs play an important role in the anthocyanin synthesis in plants. This work aimed to clone the MYB gene related to anthocyanin synthesis in the petals of Rosa rugose, and explore the relationship between them to lay a good foundation for gene engineering improvement of R. rugose. Based on the transcriptional data, a full-length cDNA sequence of MYB Gene, RrMYB113 (GenBank accession Nos MG720012), was cloned at the first time from the petals of Rosa rugose “Zi zhi” with RT-PCR and RACE methods. The full-length cDNA is 885 bp with an open reading frame of 654 bp, encoding 216 amino acids. The derived RrMYB113 protein has a molecular weight of 25,297.64 Da, a calculated pI of 9.61, a R2R3-MYB domain and bHLH binding domain, and it also has the signature motifs ((A/S/G)NDV and KPRPR(T/S)), thus belonging to Sg6 R2R3-MYB subfamily. In the secondary structure of RrMYB113 protein, there is 37.04% α-helix, 39.81% random coil, 14.81% extended peptide chain, and 8.33% β-corner. There is no transmembrane domain and no signal peptide cleavage site, seventeen Ser phosphorylation sites, fifteen Thr phosphorylation sites, four Tyr phosphorylation sites, and no O-glycosylation sites. The expression of RrMYB113 increased with the color deepening in petals, and it expressed at a higher level in petals than in other tissues of R. rugose “Zi zhi”. These results are meaningful to reveal that RrMYB113 might be an important regulator in anthocyanin biosynthesis and coloration in the petals of R. rugose.

Cloning and Expression of Anthocyanin Biosynthesis Related Gene RrMYB6 in <i>Rosa rugosa</i>

R2R3-MYB transcription factor plays an important role in plant anthocyanin synthesis. Based on the transcriptional database of Rosa rugosa, one MYB transcription factor related to floral color, RrMYB6, was cloned. By using bioinformatics analysis method, cloning MYB gene and analyzing its function in anthocyanin biosynthesis regulation, we hope to lay a solid foundation for new color variety breeding of R. rugosa. Using the R. rugosa “Zi zhi” as the material, we obtained the total length of cDNA of RrMYB6 by RT-PCR and RACE. By analyzing its bioinformatics, we found that the formula of the protein was C1491H2368N452O470S17, molecular weight was 34690.97 Da, the theoretical pI was 8.74. In addition, it belonged to unstable protein with an unstable index at 50.59, and it was also a hydrophilic protein with the total average hydrophobic index at -0.847. In the secondary structure of RrMYB6 protein, the Alpha helix accounted for 32.35%, random coil was 47.39%, extended strand was 11.11%, and beta turn was 9.15%. The sequence analysis showed that RrMYB6 had a typical R2R3-MYB domain and bHLH binding domain, and it also had an N1, C1, C2 inhibitory motif, belonging to the Sg4 subfamily MYB protein. What’s more, evolutionary analysis indicated that the RrMYB6 protein was closely related with the MYB protein in Rosacea family, while it was far from those in other families. The expression analysis showed that RrMYB6 protein decreased with the color of petals deeping, and its expression was the lowest in the petals while the highest in stamens. According to the above results, it was speculated that RrMYB6 was involved in regulating the anthocyanin synthesis of R. rugosa, which belonged to negative regulatory mechanism.

Selective separation of iron and scandium from Bayer Sc-bearing red mud

In this study,we investigated the separation of iron and scandium from Sc-bearing red mud.The red mud object of our study contained 31.11 wt%total iron(TFe),0.0045 wt%Sc,hematite(Fe_(2)O_(3))and ferrosilite(FeO·SiO_(2))as the main Fe-bearing minerals.The Sc-bearing red mud was treated by a novel deep reduction roasting and magnetic separation process that includes the addition of coke and CaO to extract Fe and enriching Sc from the Sc-bearing red mud.The addition of coke and CaO enhances the transformation of hematite(Fe_(2)O_(3))to metallic iron(Fe~0)and magnetite(Fe_(3)O_(4))as well as the transformation of ferrosilite into metallic iron(Fe~0).The test results show that utilizing the new process a Fe concentrate with a TFe content of 81.22 wt%and Fe recovery of 92.96%was obtained.Furthermore,magnetic separation tailings with Sc content of 0.0062 wt%and Sc recovery of 98.65%were also obtained.The test results were achieved under the following process conditions:roasting temperature of 1373 K,roasting time of 45 min,calcium oxide dosage of 20 wt%,coke dosage of 25 wt%,grinding fineness of90%<0.04 mm,and magnetic field intensity of 0.24 T.The major minerals in the Fe concentrate are metallic iron(Fe~0)and magnetite(Fe_(3)O_(4)).The main minerals in the magnetic separation tailings with a low TFe content of 2.62%are CaO·SiO_(2),Na_(2)O·SiO_(2),FeO·SiO_(2),Ca_(3)Fe_(2)Si_(3)O_(12),CaAl_(2)SiO_6 and CaFe(SiO_(3))_(2).

Enhancement of silicon sub‑bandgap photodetection by helium‑ion implantation

Silicon sub-bandgap photodetectors can detect light at the infrared telecommunication wavelengths but with relatively weak photo-response.In this work,we demonstrate the enhancement of sub-bandgap photodetection in silicon by helium-ion implantation,without afecting the transparency that is an important benefcial feature of this type of photodetectors.With an implantation dose of 1×10^(13)ions/cm^(2),the minimal detectable optical power can be improved from−33.2 to−63.1 dBm,or,by 29.9 dB,at the wavelength of 1550 nm,and the photo-response at the same optical power(−10 dBm)can be enhanced by approximately 18.8 dB.Our work provides a method for strategically modifying the intrinsic trade-of between transparency and strong photo-responses of this type of photodetectors.

Superconducting nanowire multi-photon detectors enabled by current reservoirs

Single-photon detectors are ubiquitous devices in quantum-photonic-based communication,computation,metrology,and sensing.In these applications,N-fold coincidence photon counting is often needed,for example,to characterize entanglement.However,N-fold coincidence photon counting typically requires N individual singlephoton detectors and associated bias and readout electronics,and these resources could become prohibitive if N goes large and the detectors need to work at cryogenic temperatures.Here,to break this limit on N,we propose a device architecture based on N cascaded photosensitive superconducting nanowires and one wider nanowire that functions as a current reservoir.We show that by strategically designing the device,the network of these superconducting nanowires can work in a synergic manner as an n-photon detector,where n can be from 1 to N,depending on the bias conditions.We therefore name the devices of this type superconducting nanowire multi-photon detectors(SNMPDs).In addition to its simple one-port bias and readout circuitry,the coincidences are counted internally in the detector,eliminating the need for external multi-channel,time-correlated pulse counters.We believe that the SNMPDs proposed in this work could open avenues towards conveniently measuring high-order temporal correlations of light and characterizing multi-photon entanglement.