Search

In the version of this Article originally published, the affiliation for author Yuh-Ru Julie Lee was incorrect; the correct affiliation is '2Department of Plant Biology, College of Biological Sciences, University of California, Davis, CA, USA'. This has now been amended in all versions of the Article.

The evolutionarily conserved MAP65 family proteins bundle anti-parallel microtubules (MTs). In Arabidopsis thaliana, mutations in the MAP65-3 gene lead to serious defects in MT organization in the phragmoplast and cause failures in cytokinesis. However, the functions of other ArabidopsisMAP65 isoforms are largely unknown. MAP65 functions were analyzed based on genetic interactions among different map65 mutations. Live-cell imaging and immunolocalization experiments revealed dynamic activities of two closely related MAP65 proteins in dividing cells. The map65-4 mutation caused synthetic lethality with map65-3 although map65-4 alone did not cause a noticeable phenotype. Furthermore, the introduction of an extra copy of the MAP65-4 gene significantly suppressed defects in cytokinesis and seedling growth caused by map65-3 because of restoring MT engagement in the spindle midzone. During mitosis, MAP65-4 first appeared at the preprophase band and persisted at the cortical division site afterwards. It was also concentrated on MTs in the spindle midzone and the phragmoplast. In the absence of MAP65-3, MAP65-4 exhibited greatly enhanced localization in the midzone of developing phragmoplast. Therefore, we have uncovered redundant but differential contributions of MAP65-3 and MAP65-4 to engaging and bundling anti-parallel MTs in the phragmoplast and disclosed a novel action of MAP65-4 at the cortical cell division site.

Fruit color is an important trait influencing the commercial value of eggplant fruits. Three dominant genes (D , P and Y) cooperatively control the anthocyanin coloration in eggplant fruits, but none has been mapped. In this study, two white-fruit accessions (19 141 and 19 147) and their F2 progeny, with 9:7 segregation ratio of anthocyanin pigmented versus non-pigmented fruits, were used for mapping the D and P genes. A high-density genetic map was constructed with 5270 SNPs spanning 1997.98 cM. Three QTLs were identified, including two genes on chromosome 8 and one on chromosome 10. Gene expression analyses suggested that the SmANS on chromosome 8 and SmMYB1 on chromosome 10 were the putative candidate genes for P and D , respectively. We further identified (1) a SNP leading to a premature stop codon within the conserved PLN03176 domain of SmANS in 19 141, (2) a G base InDel in the promoter region leading to an additional cis -regulatory element and (3) a 6-bp InDel within the R2-MYB DNA binding domain of SmMYB1 , in 19 147. Subsequently, these three variations were validated by PARMS technology as related to phenotypes in the F2 population. Moreover, silencing of SmANS or SmMYB1 in the purple red fruits of F1 (E3316) led to inhibition of anthocyanin biosynthesis in the peels. Conversely, overexpression of SmANS or SmMYB1 restored anthocyanin biosynthesis in the calli of 19 141 and 19 147 respectively. Our findings demonstrated the epistatic interactions underlying the white color of eggplant fruits, which can be potentially applied to breeding of eggplant fruit peel color. [ABSTRACT FROM AUTHOR]

A series of niobate-phosphate and niobate-silicate glasses doped with Eu[sup 3+] ions were prepared. The emissions, phonon-side band spectra, and fluorescence lifetimes of these glasses were studied and the intensity parameters of Eu[sup 3+] were obtained. The temperature dependence of emission intensity of the Eu[sup 3+] ion in these niobate glasses was investigated. The temperature-quenching rates were determined. The results indicate that in niobate glasses, as the concentration of Nb[sub 2]O[sub 5] increases, the covalence becomes stronger, the symmetry becomes lower and the electron-phonon coupling strength becomes stronger. Thus, the lifetimes become shorter, and the nonradiative transition processes and the temperature-quenching effect become stronger. [ABSTRACT FROM AUTHOR]

GaN nanowires (NWs) were grown on Ni- and Au/Ni-coated Si (100) substrate by chemical vapor deposition via reaction of metallic Ga and NH3. It was found that the Au/Ni layer tends to form liquid droplets with more uniform size distribution and regular spherical shape under annealing, which facilitates the growth of straight and long NWs. The effects of NH3/N2 ratio on NW growth are different for Ni and Au/Ni catalysts, due to the competition between the vapor-solid (VS) and vapor-liquid-solid (VLS) growth. The XRD analyses indicate that with decreasing NH3 flow rate, [0001] axial growth becomes dominant with the formation of NiGa4 catalyst. [ABSTRACT FROM AUTHOR]

In this paper, we observed that in Er3+/Yb3+ codoped nanocrystals (NC), with the decreasing particle size and the increasing Yb3+ concentration, the upconversion luminescence (UCL) of the red emissions of gradually increased, while the green emissions of gradually diminished under 980nm diode laser excitation. In NC with lower Yb3+ concentration, both the red and green emissions result from a two-photon excitation. In NC with higher Yb3+ concentration, the red emissions result from a two-photon excitation, while the green emissions dominantly result from a three-photon excitation. A model was provided for explaining the above UCL phenomena. [Copyright &y& Elsevier]

Aim: To investigate the types, associated anomalies and postnatal outcomes of fetal hepatic venous system (HVS) variants by ultrasound in China.Material and Methods: A large-scale and prospective investigation of HVS variants for low-risk singleton pregnant women was performed in three academic tertiary referral care centers in China. Ultrasound imaging wasused for the identification and follow-up of anatomical variants. Follow-up was conducted once every four weeks prenatally and every two months postnatally, mainly concerned on the adverse events that may appear.Results: There were 20848 cases with anatomical variants of fetal HVS identified from 46179 candidates during the study period. Following the anatomical position of variants occurring, four main divisions were present: main portal vein variants (17.9%), intrahepatic portal vein variants (21.30%), intrahepatic persistent right umbilical vein (0.27%) and hepatic vein variants (5.67%). In the fetal period, the pregnancy of all cases was normally continued, except that the pregnancy of two cases, which were associated with multiple anomalies and were terminated by their parents. After birth, approximately 99.47% of the cases with isolated variants orbeing associated no clinic significant anomalies were normally alive. Approximately 0.50% cases were associated with simple ventricular septum defect or tetralogy of Fallot and further treatment was needed.Conclusion: The anatomical variants of fetal HVS may appear as numerical, morphological or positional variants of MPV, intrahepatic PV branches, intrahepatic PRUV and HVs. The majority of cases are isolated or their associated anomalies are not clinically significant and have normal lifeafter birth. [ABSTRACT FROM AUTHOR]

Light-induced spectral change and its restore process in the dark of nanocrystalline Y2O3:Tb were studied. It was observed that the intensity in 4f5d band increased by ultraviolet and visible irradiation. The smaller the particle size and the shorter the wavelength is, the larger the light-induced luminescent enhancement is. Two restore components were observed, corresponding to two defects, the internal and the surface. The studies on electron spin resonance (ESR) spectra indicate that optical irradiation eliminated the dangling Y–O bonds in the surface. [Copyright &y& Elsevier]

Ultraviolet light-irradiation induced spectral change was studied in cubic nanocrystalline Y2O3:Eu3+. Under the irradiation of the ultraviolet lights separated from xenon lamp, the excited charge transfer band of Eu3+ decreased after irradiation. The smaller the particle size and the shorter the wavelength, the larger the spectral change. It was attributed to the local structural change surrounding Eu3+ ions in/near the surface. Under the irradiation of the 266-nm pulsed laser, some Eu3+ in nanoparticles was reduced to Eu2+. [Copyright &y& Elsevier]