<i>miR-34a</i> Regulates Lipid Droplet Deposition in 3T3-L1 and C2C12 Cells by Targeting LEF1

Intramuscular fat (IMF) content plays a key role in improving the flavor and palatability of pork. The IMF content varies between species, breeds, and individuals of the same breed. Hence, it is necessary to elucidate the mechanisms of IMF deposition to improve pork quality. Herein, the IMF content in the longissimus dorsi muscles of 29 Laiwu pigs was detected and divided into two groups, the H group (IMF > 12%) and the L group (IMF miR-34a was found to be increased in the H group and 3T3-L1-derived adipocytes, while Lef1 was decreased. Luciferase reporter assays demonstrated that Lef1 was a potential target of miR-34a. Mechanism analysis revealed that miR-34a could increase lipid droplet deposition in 3T3-L1 and C2C12 cells by dampening the suppressive function of Lef1 on the transcription of adipogenic markers (i.e., Pparg, Cebpa, Fabp4, and Plin1). Moreover, overexpression of miR-34a could enhance the lipid deposition in the co-culture system of 3T3-L1 and C2C12 cells as well as in C2C12 cells cultured with conditioned medium from the progress of adipocyte differentiation. Taken together, our study indicated that miR-34a was an important positive modulator in the regulation of fatty metabolism and fat deposition by inhibiting the suppressive function of Lef1. These results might provide insight for the exploration of potential strategies to promote intramuscular fat deposition in livestock

miR-34a Regulates Lipid Droplet Deposition in 3T3-L1 and C2C12 Cells by Targeting LEF1

Intramuscular fat (IMF) content plays a key role in improving the flavor and palatability of pork. The IMF content varies between species, breeds, and individuals of the same breed. Hence, it is necessary to elucidate the mechanisms of IMF deposition to improve pork quality. Herein, the IMF content in the longissimus dorsi muscles of 29 Laiwu pigs was detected and divided into two groups, the H group (IMF &gt; 12%) and the L group (IMF &lt; 5%). RNA sequencing analysis showed 24 differentially expressed (DE) miRNA, and GO and KEGG analysis demonstrated that the DE miRNAs were significantly enriched in lipid metabolic process, lipid storage, Wnt, mTOR, and PPAR signaling pathways. miR-34a was found to be increased in the H group and 3T3-L1-derived adipocytes, while Lef1 was decreased. Luciferase reporter assays demonstrated that Lef1 was a potential target of miR-34a. Mechanism analysis revealed that miR-34a could increase lipid droplet deposition in 3T3-L1 and C2C12 cells by dampening the suppressive function of Lef1 on the transcription of adipogenic markers (i.e., Pparg, Cebpa, Fabp4, and Plin1). Moreover, overexpression of miR-34a could enhance the lipid deposition in the co-culture system of 3T3-L1 and C2C12 cells as well as in C2C12 cells cultured with conditioned medium from the progress of adipocyte differentiation. Taken together, our study indicated that miR-34a was an important positive modulator in the regulation of fatty metabolism and fat deposition by inhibiting the suppressive function of Lef1. These results might provide insight for the exploration of potential strategies to promote intramuscular fat deposition in livestock

Estimation of Fuel Water Content in the Forest Ecotone of Guangzhou Based on the PROSAIL Model

Fuel moisture content (FMC), which is the ratio of equivalent water thickness (EWT) to dry matter content (DMC), plays a crucial role in the estimation of vegetation ignition probability and the fire propagation rate. The PROSAIL model can adequately simulate the canopy reflectance of vegetation, with the input of field-measured data into the model ensuring conformity with the ecological rules. If the EWT and DMC can be estimated by an empirical statistical method according to the reflectance spectrum, the universality of the physical model and the efficiency of the empirical statistical method can be considered. In this study, a fast and versatile method is established for estimating FMC based on the EWT, DMC, leaf area index measured data, and the PROSAIL model. The Normalized Difference Infrared Index (NDII) and Normalized Dry Matter Index (NDMI) were obtained from the spectral curves, with the results showing an obvious linear relationship between the NDII and EWT, NDMI, and DMC. Therefore, EWT and DMC can be estimated using the NDII and NDMI. The accuracy of the estimation results is verified to be high. The estimation model can be extended to Landsat 8 data to estimate FMC. The estimated FMC data verified by the measured data showed that R² was 0.743 and the RMSE was 34.2%. The model accuracy was reliable owing to large dynamic changes in the FMC. However, the estimated value of the FMC shifted significantly to the left during this study. The reasons for this are as follows: 1) The field-measured points are not sufficient to support the analysis according to different vegetation types, and the physical and chemical properties of different types are varied, leading to altered simulated spectral curves; 2) The vegetation spectrum is sensitive to the DMC at 1,650 nm, 1,720 nm, and 2,270 nm bands, and the sensitivity near the 1,650 nm and 1,720 nm bands is greater than that at 2,270 nm. However, because the Landsat 8 image does not have a 1,720 nm band, the 2,270 nm band was selected to calculate the NDMI, making the value of the estimated DMC too large, resulting in a small value of the estimated FMC and a significant shift to the left; 3) 1,650 nm and 2,270 nm are not in the central wavelength of the two bands of Landsat 8; therefore, the estimated DMC and FMC are shifted. In addition, the fast and versatile method, which is established based on the EWT, DMC, leaf area index measured data and the PROSAIL model, can realize large-scale and high-precision monitoring of the FMC, providing a scientific reference for forest fire prevention

Simultaneous light emission and detection of an AlGaInP quantum well diode

When a quantum well (QW) diode is biased with a forward voltage and illuminated with an external shorter-wavelength light, the device simultaneously emits and detects light, with the injected current and the induced current mixed inside the wells. Separating these superimposed and dynamic electrical signals is useful for the development of multifunctional displays that can simultaneously transmit and receive light signals. By utilizing the unique overlap between the electroluminescence and detection spectra, we establish a wireless optical communication system using two AlGaInP diodes that have identical QW structures. The communication distance is 25 m, with one diode functioning as the transmitter and the other as the receiver. In particular, at the receiver end, the QW diode demonstrates simultaneous light emission and reception ability, and the mixed signals can be efficiently extracted, suggesting great potential for applications from light communication to advanced displays