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Adventitious root (AR) formation is a critical factor in the vegetative propagation of forestry and horticultural plants. Competence for AR formation declines in many species during the miR156/SPL-mediated vegetative phase change. Auxin also plays a regulatory role in AR formation. In apple rootstock, both high miR156 expression and exogenous auxin application are prerequisites for AR formation. However, the mechanism by which the miR156/SPL module interacts with auxin in controlling AR formation is unclear. In this paper, leafy cuttings of juvenile (Mx-J) and adult (Mx-A) phase Malus xiaojinensis were used in an RNA-sequencing experiment. The results revealed that numerous genes involved in phytohormone signaling, carbohydrate metabolism, cell dedifferentiation, and reactivation were downregulated in Mx-A cuttings in response to indole butyric acid treatment. Among the differentially expressed genes, an HD-ZIP transcription factor gene, MxHB13, was found to be under negative regulation of MdSPL26 by directly binding to MxHB13 promoter. MxTIFY9 interacts with MxSPL26 and may play a role in co-repressing the expression of MxHB13. The expression of MxTIFY9 was induced by exogenous indole butyric acid. MxHB13 binds to the promoter of MxABCB19-2 and positively affects the expression. A model is proposed in which MxHB13 links juvenility-limited and auxin-limited AR recalcitrance mechanisms in Mx-A.

Kallikrein-related peptidases (KLK) have 15 members, which are the largest family of human serine proteases known so far, but there is no report about KLK in yak. In this study, Six members of yak KLK gene family were selected as the research objects, including KLK1, KLK4, KLK5, KLK6, KLK7, and KLK15. The functions of yak KLK family members were predicted and analyzed by Expasy, STRING, R language and other software. The molecular weight of KLK proteins in yak ranged from 17276. 46-31884. 23 Da, and grand average of hydropathicity of the KLK proteins is less than 0, which indicated that they all belong to hydrophilic proteins; The phylogenetic tree showed that KLK5 and KLK1 are highly similar to the same family members, while different species of KLK7 differ in motif composition and gene structure. Protein–protein interaction analysis showed that KLK5, KLK6, and KLK7 interacted with serine protease inhibitor Kazal type 5(SPINK5), a serine protease inhibitor, while KLK7 and KLK6 interacted with corneodesmosin (CDSN); Go enrichment analysis showed that the KLK gene family was mainly enriched in the regulation of platelet alpha granules, endopeptidase activity, epidermal development and serine hydrolase activity. And the expression of KLK7 in yak skin was higher than that of KLK5, KLK6 and KLK10. Our results not only enriched the KLK gene family information and obtained the interaction gene enrichment pathway, but also provided a theoretical basis for further transition to in vitro experiments and formulation of experimental schemes.

Apple (Malus domestica Borkh.) is not only an important fruit crop distributed worldwide, but also a common model plant. However, the lack of efficient genetic transformation procedures for apples limits the in-depth studies of their gene functions. Although leaf-regenerated adventitious shoots (LRAS) are a prerequisite for successful genetic transformation of apple, little is known about the underlying molecular mechanism of LRAS. Here, we identified the WUSCHEL-related homeobox (WOX) transcription factor in apple, MdWOX4-2, which was a transcriptional activator. Gene expression as well as morphological and histological observations revealed that MdWOX4-2 is involved in the development of LRAS. Overexpression of MdWOX4-2 conferred higher regenerative capacity in transgenic tobacco (Nicotiana tabacum) as compared to the wild type (WT). The combined results of the yeast one-hybrid (Y1H), electrophoretic mobility shift assay (EMSA), dual luciferase assays, and transient transactivation assay, revealed that MdWOX4-2 directly bound to and activated the MdLBD41 promoter. Moreover, transgenic experiments further demonstrated that MdLBD41 could significantly enhance the formation of adventitious shoot in transgenic tobacco. Collectively, our findings demonstrate that MdWOX4-2 is important for regulating the LRAS development by activating MdLBD41.

γ-Aminobutyric Acid (GABA), a four-carbon non-protein amino acid, is a significant component of the free amino acid pool in most prokaryotic and eukaryotic organisms. GABA is involved in pH regulation, maintaining C/N balance, plant development and defence, as well as a compatible osmolyte and an alternative pathway for glutamate utilization via anion flux. Glutamate decarboxylase (GAD, EC 4.1.1.15) and GABA transaminase (GABA-T, EC 2.6.1.19) are two key enzymes involved in the synthesis and metabolism of GABA. Recently, GABA transporters (GATs), protein and aluminium-activated malate transporter (ALMT) proteins which function as GABA receptors, have been shown to be involved in GABA regulation. However, there is no report on the characterization of apple GABA pathway genes. In this study, we performed a genome-wide analysis and expression profiling of the GABA pathway gene family in the apple genome. A total of 24 genes were identified including five GAD genes (namely MdGAD 1–5), two GABA-T genes (namely MdGABA-T 1,2), 10 GAT genes (namely GAT 1–10) and seven ALMT genes (namely MdALMT1–7). These genes were randomly distributed on 12 chromosomes. Phylogenetic analyses grouped GABA shunt genes into three clusters—cluster I, cluster II, and cluster III—which had three, four, and five genes, respectively. The expression profile analysis revealed significant MdGAD4 expression levels in both fruit and flower organs, except pollen. However, there were no significant differences in the expression of other GABA shunt genes in different tissues. This work provides the first characterization of the GABA shunt gene family in apple and suggests their importance in apple response to abiotic stress. These results can serve as a guide for future studies on the understanding and functional characterization of these gene families.

Plastid-nucleus retrograde signaling (PNRS) play essential roles in regulating nuclear gene expression during plant growth and development. Excessive reactive oxygen species can trigger PNRS. We previously reported that in apple (Malus domestica Borkh.) seedlings, the expression of microRNA156 (miR156) was significantly low in the adult phase, which was accompanied by high levels of hydrogen peroxide (H2O2) accumulation in chloroplasts. However, it was unclear whether adult-phase-specific chloroplast H2O2 may induce PNRS and affect miR156 expression, or miR156 triggers adult phase PNRS during the ontogenesis. In this paper, we examined the relationship between miR156 levels and six PNRS components in juvenile and adult phase leaves from &lsquo, Zisai Pearl&rsquo, &times, &lsquo, Red Fuji&rsquo, hybrids. We found that PNRS generated by singlet oxygen (1O2), the photosynthetic redox state, methylerythritol cyclodiphosphate (MEcPP), SAL1-3-phosphoadenosine 5-phosphate (PAP) and WHIRLY1 were not involved. The accumulation of Mg-protoporphyrin IX (Mg-Proto IX), the expression of the synthetic genes MdGUN5 and MdGUN6, and Mg-Proto IX PNRS related nuclear genes increased with ontogenesis. These changes were negatively correlated with miR156 expression. Manipulating Mg-Proto IX synthesis with 5-aminolevulinic acid (ALA) or gabaculine did not affect miR156 expression in vitro shoots. In contrast, modulating miR156 expression via MdGGT1 or MdMIR156a6 transgenesis led to changes in Mg-Proto IX contents and the corresponding gene expressions. It was concluded that the Mg-Proto IX PNRS was regulated downstream of miR156 regardless of adult-phase-specific plastid H2O2 accumulation. The findings may facilitate the understanding of the mechanism of ontogenesis in higher plants.

The vegetative phase change in flowering plants is controlled by microRNA156 (miR156) under transcriptional regulation. However, the developmental signals upstream of miR156 are not well understood. The glutathione/glutathione disulfide (GSH/GSSG) ratios and GSH levels decline significantly during phase change, which is consistent with miR156 expression in apple (Malus domestica Borkh.). Here, we found that the content of protein conjugated glutathione was remarkably higher in chloroplasts and nuclei of adult than juvenile phase apple hybrids. The decrease in miR156 expression was most relevant to the activities of serine acetyltransferase (SAT) and soluble γ-glutamyl transpeptidase (GGT), and the expressions of MdGGT1 or MdSATs. Transgenic apples over-expressing MdMIR156 or miR156-mimetic (MIM156) did not alter MdGGT1 expression or the soluble GGT activity. Inhibition of GGT activity with serine-borate complex or acivicin led to significant reduction in GSH content, the GSH/GSSG ratio, and the expressions of MdMIR156a5, MdMIR156a12, and miR156. Depletion of GSH with diethyl maleate without altering GGT activity caused a dramatic decrease in the expression of MdMIR156a5, MdMIR156a12, and miR156. Manipulating GGT activity and GSH homeostasis by transgenic over-expressing or RNAi MdGGT1 increased or decreased MdMIR156a5 and MdMIR156a12 levels, respectively. These data provided novel evidence that MdGGT1 participates in transcriptional level of transcription regulation of miR156 precursors during ontogenesis. HIGHLIGHTS - MdGGT1 affects thiol redox status and indirectly participates in the regulation of miR156 expression during vegetative phase change.

The high speed permanent magnet synchronous motor is widely used in the electric car, for its wide speed range, high power density and high efficiency. Firstly, a high speed permanent magnet synchronous motor for electric car is designed by traditional method based on the operating character and the design requirements of electric car. Then, the motor is simulated on the electromagnetic performance. Lastly, the prototype experiment proves the accuracy of the calculation and the rationality of the design.

An automatic measuring facility for the measurement of the energy distribution of a spot diagram based on the prototype of the Moderate Resolution Spectroradiometric Imager(MRSI) is presented in this paper. The facility consists of four main parts: 1. a microscope objective, 2. a special CCD camera, 3. a scanning system, 4. a data processing and output system which can implement data acquiring, storing and processing of images produced by the tested optical system. The facility can assess the optical imaging quality by obtaining the area of the energy distribution and find out the final image plane by comparing the spot diagram at different positions. The spot diagram gained by the CCD camera can be shown on the display screen in gray mode or color mode. The measuring facility has been developed and used in optical fabrication, assembling and evaluating of MRSI, and it is proved to be effective.

The 10-band scanning radiometer is the main payload of the Chinese polar-orbit FY-1C meteorological satellite. Its instrument configuration, detecting bands, detectors, orbital signal processor and behavior in orbit are described in this paper.

Deviation should be induced in the result of the spectral calibration of a optical remote sensor with large aperture and large field of view (FOV) because of the optical system of the calibration facility can not have a large aperture and a large FOV simultaneously. Detail analysis of the possible deviation were given for a multichannel imager and a imaging spectrometer respectively. For a imaging spectrometer, a modified method of test and data process is proposed.

For the earth observation system, most newly-designed optical imaging systems are generally based on the principle of pushbroom imaging. With the rapid development of infrared array detectors, this technology, which gives consideration to both spatial resolution and radiative sensitivity, is extended to instruments with thermal infrared wavebands. Comparing with separate detectors system, the pushbroom imaging system using array detectors possesses a wide field of view (FOV) which reduces the off-axis image quality and is harmful to the resolution of the system. The structure using array aperture in synthesized manner makes it possible to enhance both image quality and radiative sensitivity.

With the improvement of the linear-variable-filter (LVF), it is possible to design a cooled field stop using a miniature LVF. The principle, structure and characteristics of this cooled field stop are described in this paper.

The application of remote sensing is, to a greater extent, based on the quality of the sensors. The prelaunch radiant calibration and post-launch validation, which are the process of quantitatively defining the system response to known, controlled signal inputs, are among the key stages of the development procedure of a remote sensor. Calibration of a remote sensor is to develop the calibration equations that allow conversion of the counts for the sensor into Earth- exiting radiance. These radiances are the geophysical properties the instrument has been designed to measure. With solar radiation-based calibration, sphere radiation-based calibration, on-orbit calibrator and ground-based calibration, the remote sensor data can be quantitatively applied on atmosphere, environment. The precision of several methods is mentioned in the paper. The Chinese meteorological satellites had used the procedures to calibrate the sensors.

To the remote sensing devices on the satellite, there are often clouds in their field of view. From statistics, clouds usually cover about 40 percent of the earth surfaces. Most of the clouds will prevent signals in 0.3-3 micrometers from arriving the remote sensors except for thin cirrus. To those remote sensing devices or cameras aimed at getting signals from earth surface, they can only get some useless information at this time.Some research on the reflected spectrum of clouds and other main kinds of objects on earth surface is necessary to find an effective way to tell them apart. We make an analysis to the reflectance of clouds and other objects in this paper, then two spectral channels are chosen to give a judgement. A stand alone prototype device is also developed for this purpose.