Spatiotemporal formation of glands in plants is modulated by MYB-like transcription factors.

About one third of vascular plants develop glandular trichomes, which produce defensive compounds that repel herbivores and act as a natural biofactory for important pharmaceuticals such as artemisinin and cannabinoids. However, only a few regulators of glandular structures have been characterized so far. Here we have identified two closely-related MYB-like genes that redundantly inhibit the formation of glandular cells in tomatoes, and they are named as GLAND CELL REPRESSOR (GCR) 1 and 2. The GCR genes highly express in the apical cells of tomato trichomes, with expression gradually diminishing as the cells transition into glands. The spatiotemporal expression of GCR genes is coordinated by a two-step inhibition process mediated by SlTOE1B and GCRs. Furthermore, we demonstrate that the GCR genes act by suppressing Leafless (LFS), a gene that promotes gland formation. Intriguingly, homologous GCR genes from tobacco and petunia also inhibit gland formation, suggesting that the GCR-mediated repression mechanism likely represents a conserved regulatory pathway for glands across different plant species.

A HD-ZIP transcription factor specifies fates of multicellular trichomes via dosage-dependent mechanisms in tomato.

Hair-like structures are shared by most living organisms. The hairs on plant surfaces, commonly referred to as trichomes, form diverse types to sense and protect against various stresses. However, it is unclear how trichomes differentiate into highly variable forms. Here, we show that a homeodomain leucine zipper (HD-ZIP) transcription factor named Woolly controls the fates of distinct trichomes in tomato via a dosage-dependent mechanism. The autocatalytic reinforcement of Woolly is counteracted by an autoregulatory negative feedback loop, creating a circuit with a high or low Woolly level. This biases the transcriptional activation of separate antagonistic cascades that lead to different trichome types. Our results identify the developmental switch of trichome formation and provide mechanistic insights into the progressive fate specification in plants, as well as a path to enhancing plant stress resistance and the production of beneficial chemicals.

The ion-imprinted oyster shell material for targeted removal of Cd(II) from aqueous solution.

In order to realize the sustainable utilization of waste oyster shell and develop a targeted removal technology for cadmium. A novel ion-imprinted oyster shell material (IIOS) was prepared by surface imprinting technique. The prepared samples were characterized by scanning electron microscope, Fourier infrared spectrometer, X-ray diffractometer, thermogravimetric analysis and N2 adsorption-desorption. The adsorption performances of IIOS for Cd(II) from aqueous solution were studied by the single factor sequential batch, kinetics, isotherms, selectivity and recycling experiments. The characterization researches showed that IIOS was successfully prepared. The adsorption experiments indicated that the adsorption process reached equilibrium within 240 min; the maximum adsorption capacity was up to 69.1 mg g-1 with the initial Cd(II) concentration of 75 mg L-1 at pH 5; the adsorption process fitted well to the pseudo-second-order model and the Langmuir isotherm model, which revealed the chemisorption characteristic of Cd(II). Moreover, IIOS exhibited a good targeted adsorption of Cd(II) in several binary competition systems owing to the present of these imprinted cavities. The recycling experiment showed that the targeted removal ratio of IIOS for Cd(II) remained above 80% after used six times. The results of this study indicated that it is a promising prospect for waste oyster shell used as IIOS to dispose heavy metals in wastewater.

Spatio-temporal pattern and driving forces of ecosystem services in coalfields of Shanxi Pro-vince, China.

Although coal has made a huge contribution to the development of the economy and socie-ty and its economic benefits have often attracted much attention, little research has focused on the ecosystem services of coalfields. Based on remote sensing data, meteorological data, and soil data in Shanxi coalfields during 1986, 2000, and 2015, we estimated soil conservation and water yield using the InVEST model, assessed the net primary productivity of vegetation using the CASA mo-del, and estimated sand fixation using the RWEQ model. Further, we simulated the spatial patterns of ecosystem services (ESs) using the k-means cluster analysis method and analyzed the influence factors of ESs using the Geodetector model in Shanxi coalfield areas. The results showed that soil conservation service, water yield service, and sand fixation service increased continuously. The high-value area of soil conservation service was mainly concentrated in the north of Hedong coalfield and the northeast of Qinshui coalfield, while the low-value area was distributed in the southwestern edge of Datong coalfield. The high-value area of water yield service was mainly concentrated in the northeast of Qinshui coalfield, while the low-value area was distributed in the northeast of Qinshui coalfield, Xishan coalfield and northwestern Qinshui coalfield. The high-value area for vegetation production service was mainly concentrated in the southeast of Qinshui coalfield, while the low-value area was distributed in Datong coalfield, Ningwu coalfield, Xishan coalfield, and northern Hedong coalfield. The distribution of low- and high-value areas of sand fixation service was unfixed. Ecosystem service bundles could be divided into four categories. The first category belonged to soil conservation service bundle, mainly distributed in the northern Ningwu coalfield, the northern Hedong coalfield, and the northern Qinshui coalfield. The second was water yield service bundle, mainly distributed in Huoxi coalfield and southern Qinshui coalfield. The third category belonged to vegetation production service bundle, mainly distributed in parts of Qinshui coalfield. The fourth category belonged to sand fixation service bundle, mainly distributed in the southern part of Hedong coalfield and Qinshui coalfield. Soil conservation service was greatly affected by temperature, digital elevation model (DEM), and industrial output value, with q values of 0.5, 0.3, and 0.2, respectively. Water yield service was greatly affected by precipitation, temperature, and DEM, with q values of 0.8, 0.3, and 0.2, respectively. The industrial output value, precipitation, and temperature q values of vegetation production service were 0.7, 0.6, and 0.2, respectively. The main influen-cing factors of sand fixation service were precipitation, temperature, and DEM, while the q values were 0.7, 0.3, and 0.3, respectively. The spatial distribution of coalfields ESs and the relationship between multiple ESs were closely related to natural and human factors. Therefore, maintaining the coordination relationship between natural-human factors and ecological services would be helpful to the management of the land reclamation, ecological reconstruction, and the sustainable development of coalfields ecosystem.

Role of transient receptor potential cation channel subfamily M member 2 in hepatic ischemia-reperfusion injury in the mouse and the underlying mechanisms. / 瞬时受体电位阳离子通道亚家族M成员2åœ¨å°é¼ è‚ç¼ºè¡€å†çŒæ³¨æŸä¼¤æ¨¡åž‹ä¸­çš„ä½œç”¨åŠæœºåˆ¶.

OBJECTIVES: To investigate the role of transient receptor potential cation channel subfamily M member 2 (TRPM2) in hepatic ischemia-reperfusion injury of mouse (HIRI) and the possible mechanisms. METHODS: Sixty adult male C57BL/6 mice were randomly divided into 4 groups: a sham group (S group), a HIRI model group (M group), a TRPM2 adenovirus interference vector group (T group), and a TRPM2 adenovirus control vector group (C group) (n=15 in each group). The liver tissues of mice before perfusion were obtained. The efficiency of adenovirus infection was detected by fluorescence microscopy, and the silencing efficiency of adenovirus against TRPM2 was detected by real-time PCR.The abdominal aorta blood and liver tissues were collected from mice at 2, 4 and 8 h after reperfusion. The activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum of mice were detected. Hepatic pathological changes were examined by hematoxylin-eosin (HE) staining. The protein expression of TRPM2 and Rac family small GTPase 1 (RAC1) in liver tissues was detected by Western blotting. Changes of malondialdehyde (MDA), superoxide dismutase (SOD) and myeloperoxidase (MPO) activities in liver tissues were detected by enzyme-linked immunosorbent assay. RESULTS: A strong signal of green fluorescence was observed in the liver tissues of mice in the T and C groups compared to the S or M group. Compared with the S, M or C group, the expression of TRPM2 mRNA in liver tissue in the T group was significantly down-regulated (all P<0.05). The morphology of hepatocytes was normal in the S group under light microscope.Hepatic sinus dilatation, congestion, hepatocyte degeneration, central necrosis of lobule, and massive inflammatory granulocyte infiltration were observed in the M and C group, respectively. The degree of hepatocyte damage in the T group was significantly reduced compared with that in the M and C group, respectively. Compared with the S group, the serum ALT and AST activities in the M, T and C groups were significantly increased at 2, 4 and 8 h after reperfusion (all P<0.05). Compared with the M or C group, the serum ALT and AST activities in the T group were significantly lower in serum of mice at 2, 4, and 8 h after reperfusion (all P<0.05). Compared with the M or C group, the serum SOD activity in the T group was significantly increased at 2, 4, and 8 h after reperfusion (all P<0.05), while the serum MDA and MPO activities were significantly decreased (all P<0.05). The protein expression of TRPM2 and RAC1 in liver tissues in the T group were significantly lower than those in the M and C groups at 2, 4 and 8 h after reperfusion (all P<0.05). CONCLUSIONS: Pretreatment with TRPM2 adenovirus interference vector can effectively silence TRPM2 gene expression in liver tissues of mice and attenuate HIRI, which may be related to inhibiting oxidative stress and reducing the expression of RAC1 protein.

Influence of atmospheric helium on secondary clocks.

Glass-cell-based secondary clocks, including coherent population trapping (CPT) clocks, are the most used clocks in modern laboratories and in industry. However, the reported frequency accuracies of those secondary clocks were always much worse than expected, though all error sources have been previously discussed. In this report, a high-precision measurement on the spectral frequency-linewidth relation (FL-R) is first used for revealing a new error source in secondary clocks by which we answer the puzzle raised in Opt. Lett.38, 3186 (2013)10.1364/OL.38.003186.

Confocal depth-resolved fluorescence micro-X-ray absorption spectroscopy for the study of cultural heritage materials: a new mobile endstation at the Beijing Synchrotron Radiation Facility.

A confocal fluorescence endstation for depth-resolved micro-X-ray absorption spectroscopy is described. A polycapillary half-lens defines the incident beam path and a second polycapillary half-lens at 90° defines the probe sample volume. An automatic alignment program based on an evolutionary algorithm is employed to make the alignment procedure efficient. This depth-resolved system was examined on a general X-ray absorption spectroscopy (XAS) beamline at the Beijing Synchrotron Radiation Facility. Sacrificial red glaze (AD 1368-1644) china was studied to show the capability of the instrument. As a mobile endstation to be applied on multiple beamlines, the confocal system can improve the function and flexibility of general XAS beamlines, and extend their capabilities to a wider user community.

Microscopic analysis of "iron spot" on blue-and-white porcelain from Jingdezhen imperial kiln in early Ming dynasty (14th-15th century).

"Sumali," as an imported cobalt ore from overseas, was a sort of precious and valuable pigment used for imperial kilns only, which produces characteristic "iron spot" to blue-and-white porcelain in early Ming Dynasty (A.D. 14th-15th century). Although there were some old studies on it, the morphology and formation of iron spot has not been fully investigated and understood. Therefore, five selected samples with typical spot from Jingdezhen imperial kiln in Ming Yongle periods (A.D. 1403-1424) were analyzed by various microscopic analysis including 3D digital microscope, SEM-EDS and EPMA. According to SEM images, samples can be divided into three groups: un-reflected "iron spot" without crystals, un-reflected "iron spot" with crystals and reflected "iron spot" with crystals. Furthermore, 3D micro-images revealed that "iron spots" separate out dendritic or snow-shaped crystals of iron only on and parallel to the surface of glaze for which "iron spot" show strong metallic luster. Combining with microscopic observation and microanalysis on crystallization and non-crystallization areas, it indicates that firing oxygen concentration is the ultimate causation of forming reflective iron spot which has a shallower distribution below the surface and limits crystals growing down. More details about characters of "iron spot" used "Sumali" were found and provided new clues to coloration, formation mechanism and porcelain producing technology of imperial kiln from 14th to 15th centuries of China.

[Spectroscopic Studies on the Interaction of Human Serum Albumin and Water-Soluble Carboxyl Carbon Nanotubes].

The interaction between nanomaterials and biological macromolecules (including protein) is the important basis of biological safety assessments of nanomaterials. In this paper, the fluorescence spectroscopy, synchronous fluorescence spectroscopy and circular dichroism spectroscopy) were used to analyze the interaction between four water-soluble carboxyl carbon nanotubes (long-SWCNTs-COOH, short-SWCNTs-COOH, DWCNTs-COOH and MWCNTs-COOH) and human serum albumin. Results showed that the four water-soluble carboxylated carbon nanotubes could quench the intrinsic fluorescence of human serum albumin at different extents. Under the same concentration, the quenching ability of four carboxylated carbon nanotubes were in the order of DWCNTs-COOH

Lead-induced hearing loss in rats and the protective effect of copper.

Lead is a common environmental pollutant which can induce various toxic effects to humans and/or animals. This work aimed to study the hearing loss in rats induced by lead and the protective effect of copper. The auditory brainstem response (ABR) was used to study the hearing loss in rats. The results showed that lead prolonged the latencies of wave I to V of ABRs of the rats but did not affect the interpeak latencies of waves I-III, III-V, and I-V, indicating that lead could cause hearing loss in rats by impairing the cochlea. After receiving copper, the quality and the wave latencies of the ABR of the rats were restored to a certain extent, indicating that copper played a protective role in lead-induced hearing impairment. The mechanisms were also proposed that lead could cause hearing loss in rats mainly through damaging the cochlea component, and copper might antagonize the toxicity of lead in three primary ways.