A large-scale microelectromechanical-systems-based silicon photonics LiDAR.

Three-dimensional (3D) imaging sensors allow machines to perceive, map and interact with the surrounding world1. The size of light detection and ranging (LiDAR) devices is often limited by mechanical scanners. Focal plane array-based 3D sensors are promising candidates for solid-state LiDARs because they allow electronic scanning without mechanical moving parts. However, their resolutions have been limited to 512 pixels or smaller2. In this paper, we report on a 16,384-pixel LiDAR with a wide field of view (FoV, 70° × 70°), a fine addressing resolution (0.6° × 0.6°), a narrow beam divergence (0.050° × 0.049°) and a random-access beam addressing with sub-MHz operation speed. The 128 × 128-element focal plane switch array (FPSA) of grating antennas and microelectromechanical systems (MEMS)-actuated optical switches are monolithically integrated on a 10 × 11-mm2 silicon photonic chip, where a 128 × 96 subarray is wire bonded and tested in experiments. 3D imaging with a distance resolution of 1.7 cm is achieved with frequency-modulated continuous-wave (FMCW) ranging in monostatic configuration. The FPSA can be mass-produced in complementary metal-oxide-semiconductor (CMOS) foundries, which will allow ubiquitous 3D sensors for use in autonomous cars, drones, robots and smartphones.

Key mRNAs and lncRNAs of pituitary that affect the reproduction of FecB + + small tail han sheep.

BACKGROUND: The pituitary directly regulates the reproductive process through follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Transcriptomic research on the pituitaries of ewes with different FecB (fecundity Booroola) genotypes has shown that some key genes and lncRNAs play an important role in pituitary function and sheep fecundity. Our previous study found that ewes with FecB + + genotypes (without FecB mutation) still had individuals with more than one offspring per birth. It is hoped to analyze this phenomenon from the perspective of the pituitary transcriptome. RESULTS: The 12 Small Tail Han Sheep were equally divided into polytocous sheep in the follicular phase (PF), polytocous sheep in the luteal phase (PL), monotocous sheep in the follicular phase (MF), and monotocous sheep in the luteal phase (ML). Pituitary tissues were collected after estrus synchronous treatment for transcriptomic analysis. A total of 384 differentially expressed genes (DEGs) (182 in PF vs. MF and 202 in PL vs. ML) and 844 differentially expressed lncRNAs (DELs) (427 in PF vs. MF and 417 in PL vs. ML) were obtained from the polytocous-monotocous comparison groups in the two phases. Functional enrichment analysis showed that the DEGs in the two phases were enriched in signaling pathways known to play an important role in sheep fecundity, such as calcium ion binding and cAMP signaling pathways. A total of 1322 target relationship pairs (551 pairs in PF vs. MF and 771 pairs in PL vs. ML) were obtained for the target genes prediction of DELs, of which 29 DEL-DEG target relationship pairs (nine pairs in PF vs. MF and twenty pairs in PL vs. ML). In addition, the competing endogenous RNA (ceRNA) networks were constructed to explore the regulatory relationships of DEGs, and some important regulatory relationship pairs were obtained. CONCLUSION: According to the analysis results, we hypothesized that the pituitary first receives steroid hormone signals from the ovary and uterus and that VAV3 (Vav Guanine Nucleotide Exchange Factor 3), GABRG1 (Gamma-Aminobutyric Acid A Receptor, Gamma 1), and FNDC1 (Fibronectin Type III Domain Containing 1) played an important role in this process. Subsequently, the reproductive process was regulated by gonadotropins, and IGFBP1 (Insulin-like Growth Factor Binding Protein 1) was directly involved in this process, ultimately affecting litter size. In addition, TGIF1 (Transforming Growth Factor-Beta-Induced Factor 1) and TMEFF2 (Transmembrane Protein With EGF Like And Two Follistatin Like Domains 2) compensated for the effect of the FecB mutation and function by acting on TGF-ß/SMAD signaling pathway, an important pathway for sheep reproduction. These results provided a reference for understanding the mechanism of multiple births in Small Tail Han Sheep without FecB mutation.

Tunable mid-infrared photodetector based on graphene plasmons controlled by ferroelectric polarization for micro-spectrometer.

Surface plasmonic detectors have the potential to be key components of miniaturized chip-scale spectrometers. Graphene plasmons, which are highly confined and gate-tunable, are suitable forin situlight detection. However, the tuning of graphene plasmonic photodetectors typically relies on the complex and high operating voltage based on traditional dielectric gating technique, which hinders the goal of miniaturized and low-power consumption spectrometers. In this work, we report a tunable mid-infrared (MIR) photodetector by integrating of patterned graphene with non-volatile ferroelectric polarization. The polarized ferroelectric thin film provides an ultra-high surface electric field, allowing the Fermi energy of the graphene to be manipulated to the desired level, thereby exciting the surface plasmon polaritons effect, which is highly dependent on the free carrier density of the material. By exciting intrinsic graphene plasmons, the light transmittance of graphene is greatly enhanced, which improves the photoelectric conversion efficiency of the device. Additionally, the electric field on the surface of graphene enhanced by the graphene plasmons accelerates the carrier transfer efficiency. Therefore, the responsivity of the device is greatly improved. Our simulations show that the detectors have a tunable resonant spectral response of 9-14µm by reconstructing the ferroelectric domain and exhibit a high responsivity to 5.67 × 105A W-1at room temperature. Furthermore, we also demonstrate the conceptual design of photodetector could be used for MIR micro-spectrometer application.

Patterned Nanoparticle Arrays Fabricated Using Liquid Film Rupture Self-Assembly.

Self-assembly is an important bottom-up fabrication approach based on accurate manipulation of solid-air-liquid interfaces to construct microscale structures using nanoscale materials. This approach plays a substantial role in the fabrication of microsensors, nanosensors, and actuators. Improving the controllability of self-assembly to realize large-scale regular micro/nano patterns is crucial for this approach's further development and wider applications. Herein, we propose a novel strategy for patterning nanoparticle arrays on soft substrates. This strategy is based on a unique process of liquid film rupture self-assembly that is convenient, precise, and cost-efficient for mass manufacturing. This approach involves two key steps. First, suspended liquid films comprising monolayer polystyrene (PS) spheres are realized via liquid-air interface self-assembly over prepatterned microstructures. Second, these suspended liquid films are ruptured in a controlled manner to induce the self-assembly of internal PS spheres around the morphological edges of the underlying microstructures. This nanoparticle array patterning method is comprehensively investigated in terms of the effect of the PS sphere size, morphological effect of the microstructured substrate, key factors influencing liquid film-rupture self-assembly, and optical transmittance of the fabricated samples. A maximum rupture rate of 95.4% was achieved with an optimized geometric and dimensional design. Compared with other nanoparticle-based self-assembly methods used to form patterned arrays, the proposed approach reduces the waste of nanoparticles substantially because all nanoparticles self-assemble around the prepatterned microstructures. More nanoparticles assemble to form prepatterned arrays, which could strengthen the nanoparticle array network without affecting the initial features of prepatterned microstructures.

An anti-scratch flexible SERS substrate for pesticide residue detection on the surface of fruits and vegetables.

We propose an anti-scratch flexible surface-enhanced Raman scattering substrate with arrayed nanocavity microstructures fabricated by colloidal lithography. The nanocavity microstructure of the substrate can well protect the inner gold nanoparticles during wipe sampling. The prepared flexible substrate was able to detect 4-aminothiophenol (4-ATP) with a concentration down to 1 fM. Furthermore, the substrate was used to detect 6-BA residues on the surface of apples and bean sprouts through wipe sampling, which shows great potential in the field of rapid on-site detection, especially in the detection of pesticide residues on the surface of fruits and vegetables.

The Improved Milk Quality and Enhanced Anti-Inflammatory Effect in Acetylserotonin-O-methyltransferase (ASMT) Overexpressed Goats: An Association with the Elevated Endogenous Melatonin Production.

BACKGROUND: Transgenic animal production is an important means of livestock breeding and can be used to model pharmaceutical applications. METHODS: In this study, to explore the biological activity of endogenously produced melatonin, Acetylserotonin-O-methyltransferase (ASMT)-overexpressed melatonin-enriched dairy goats were successfully generated through the use of pBC1-ASMT expression vector construction and prokaryotic embryo microinjection. RESULTS: These transgenic goats have the same normal phenotype as the wild-type goats (WT). However, the melatonin levels in their blood and milk were significantly increased (p < 0.05). In addition, the quality of their milk was also improved, showing elevated protein content and a reduced somatic cell number compared to the WT goats. No significant changes were detected in the intestinal microbiota patterns between groups. When the animals were challenged by the intravenous injection of E. coli, the ASMT-overexpressed goats had a lower level of pro-inflammatory cytokines and higher anti-inflammatory cytokines compared to the WT goats. Metabolic analysis uncovered a unique arachidonic acid metabolism pattern in transgenic goats. CONCLUSIONS: The increased melatonin production due to ASMT overexpression in the transgenic goats may have contributed to their improved milk quality and enhanced the anti-inflammatory ability compared to the WT goats.

The Interface between Nanoenergy and Self-Powered Electronics.

In recent decades, nanogenerators based on several techniques such as triboelectric effects, piezoelectric effects, or other mechanisms have experienced great developments. The nanoenergy generated by nanogenerators is supposed to be used to overcome the problem of energy supply problems for portable electronics and to be applied to self-powered microsystems including sensors, actuators, integrated circuits, power sources, and so on. Researchers made many attempts to achieve a good solution and have performed many explorations. Massive efforts have been devoted to developing self-powered electronics, such as self-powered communication devices, self-powered human-machine interfaces, and self-powered sensors. To take full advantage of nanoenergy, we need to review the existing applications, look for similarities and differences, and then explore the ways of achieving various self-powered systems with better performance. In this review, the methods of applying nanogenerators in specific circumstances are studied. The applications of nanogenerators are classified into two categories, direct utilization and indirect utilization, according to whether a treatment process is needed. We expect to offer a line of thought for future research on self-powered electronics.

Identification of genes related to resistance against S. Typhimurium in ovine macrophages.

Salmonella enteric serovar Typhimurium (S. Typhimurium) is a zoonotic pathogen causing public health hazards. Identification of genes related to macrophages resistance to S. Typhimurium and their immune mechanisms can provide a theoretical basis for disease resistance. In this study, sixty significant differentially expressed genes were screened between susceptible and resistant sheep macrophages by transcriptome RNA-seq. Eight significantly enriched GO terms and six canonical pathways were involved by GO and KEGG enrichment analysis. Furthermore, knockdown of HMOX1 and SLPI increased remarkably the clearance of S. typhimurium, but SPP1 had little effect on the clearance of S. Typhimurium within sheep macrophages. Altogether, these results suggest that many genes of macrophages were reprogrammed via S. Typhimurium infection, some of which may facilitate host defence against Salmonella, while others allow Salmonella to escape.

Exploring the roles of fecundity-related long non-coding RNAs and mRNAs in the adrenal glands of small-tailed Han Sheep.

BACKGROUND: Long non-coding RNAs (lncRNAs) can play important roles in uterine and ovarian functions. However, little researches have been done on the role of lncRNAs in the adrenal gland of sheep. Herein, RNA sequencing was used to compare and analyze gene expressions in adrenal tissues between follicular phases and luteal phases in FecBBB (MM) and FecB++ (WW) sheep, respectively, and differentially expressed lncRNAs and genes associated with reproduction were identified. RESULTS: In MM sheep, 38 lncRNAs and 545 mRNAs were differentially expressed in the adrenal gland between the luteal and follicular phases; In WW sheep, 513 differentially expressed lncRNAs and 2481 mRNAs were identified. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses indicated that differentially expressed lncRNAs and their target genes are mainly involved in the circadian rhythm, the mitogen activated protein kinase, thyroid, ovarian steroidogenesis and transforming growth factor beta signaling pathways. Differentially expressed lncRNAs can regulate reproduction by modulating genes involved in these signaling pathways and biological processes. Specifically, XLOC_254761, XLOC_357966, 105,614,839 and XLOC_212877 targeting CREB1, PER3, SMAD1 and TGFBR2, respectively, appear to play key regulatory roles. CONCLUSION: These results broaden our understanding of lncRNAs in adrenal gland of sheep and provide new insights into the molecular mechanisms underlying sheep reproduction.

Magnetic assembled 3D SERS substrate for sensitive detection of pesticide residue in soil.

Three-dimensional (3D) surface enhanced Raman scattering (SERS) substrates were produced by magnetic force assisting self-assembled nanoparticles in arrayed holes. Compared to '2D' plasmonic structures used in conventional SERS substrates, the 'hot spots' existed on whole depth of the 3D SERS substrates, which greatly enhanced the sensitivity. The prepared 3D SERS substrate was able to detect 4-aminothiophenol with a concentration down to 1 pM. Furthermore, the substrate was applied to detect hexachlorobenzene residue in soil, indicating its great potential for rapid and sensitive detection of extreme low concentrated molecules, especially pollutants residues in foods and environments.

Effect of supplemetation of Zebularine and Scriptaid on efficiency of in vitro developmental competence of ovine somatic cell nuclear transferred embryos.

Somatic cell nuclear transfer (SCNT) technology has been applied in the construction of disease model, production of transgenic animals, therapeutic cloning, and other fields. However, the cloning efficiency remains limited. In our study, to improve SCNT efficiency, brilliant cresyl blue (BCB) staining were chosen to select recipient oocytes. In addition, DNA methyltransferase inhibitor Zebularine (5 nmol/L) and histone deacetylase inhibitor Scriptaid (0.2 µmol/L) were jointly used to treat sheep donor cumulus cells and reconstructed embryo. Moreover, the expression levels of embryonic development-related genes (OCT4, SOX2, H19, IGF2 and Dnmt1) of reconstructed embryo were also detected. Using BCB + oocytes as recipient cell, donor cumulus cells and reconstructed embryos were treated with 5 nmol/L Zebularine and 0.2 µmol/L Scriptaid, the blastocyst rate in Zeb + SCR-SCNT group (28.25%) was significantly higher than SCNT (21.16%) (p < 0.05). Furthermore, results showed that expression levels of OCT4, SOX2, H19, IGF2 and Dnmt1 genes in Zeb + SCR-SCNT embryos were more similar to IVF embryos. Our study proved that 5 nmol/L Zebularine and 0.2 µmol/L Scriptaid treating with sheep donor cumulus cells and reconstructed embryos improved SCNT blastocyst rate and relieve the abnormal expression of embryonic developmental related genes.

Dissipation Analysis Methods and Q-Enhancement Strategies in Piezoelectric MEMS Laterally Vibrating Resonators: A Review.

Over the last two decades, piezoelectric resonant sensors based on micro-electromechanical systems (MEMS) technologies have been extensively studied as such sensors offer several unique benefits, such as small form factor, high sensitivity, low noise performance and fabrication compatibility with mainstream integrated circuit technologies. One key challenge for piezoelectric MEMS resonant sensors is enhancing their quality factors (Qs) to improve the resolution of these resonant sensors. Apart from sensing applications, large values of Qs are also demanded when using piezoelectric MEMS resonators to build high-frequency oscillators and radio frequency (RF) filters due to the fact that high-Q MEMS resonators favor lowering close-to-carrier phase noise in oscillators and sharpening roll-off characteristics in RF filters. Pursuant to boosting Q, it is essential to elucidate the dominant dissipation mechanisms that set the Q of the resonator. Based upon these insights on dissipation, Q-enhancement strategies can then be designed to target and suppress the identified dominant losses. This paper provides a comprehensive review of the substantial progress that has been made during the last two decades for dissipation analysis methods and Q-enhancement strategies of piezoelectric MEMS laterally vibrating resonators.

Identification of Prolificacy-Related Differentially Expressed Proteins from Sheep (Ovis aries) Hypothalamus by Comparative Proteomics.

Reproduction, as a physiologically complex process, can significantly affect the development of the sheep industry. However, a lack of overall understanding to sheep fecundity has long blocked the progress in sheep breeding and husbandry. In the present study, the aim is to identify differentially expressed proteins (DEPs) from hypothalamus in sheep without FecB mutation in two comparison groups: polytocous (PF) versus monotocous (MF) sheep at follicular phase and polytocous (PL) versus monotocous (ML) sheep at luteal phase. Totally 5058 proteins are identified in sheep hypothalamus, where 22 in PF versus MF, and 39 proteins in PL versus ML are differentially expressed, respectively. A functional analysis is then conducted including Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis to reveal the potential roles of these DEPs. The proteins ENSOARP00000020097, ENSOARP00000006714, growth hormone (GH), histone deacetylase 4 (HDAC4), and 5'-3' exoribonuclease 2 (XRN2) in PF versus MF, and bcl-2-associated athanogene 4 (BAG4), insulin-like growth factor-1 receptor (IGF1R), hydroxysteroid 11-beta dehydrogenase 1 (HSD11B1), and transthyretin (TTR) in PL versus ML appear to modulate reproduction, presumably by influencing the activities of gonadotropin-releasing hormone (GnRH). This study provides an alternative method to identify DEPs associated with sheep prolificacy from the hypothalamus. The mass spectrometry data are available via ProteomeXchange with identifier PXD013822.

Laser frequency sweep linearization by iterative learning pre-distortion for FMCW LiDAR.

We report on a laser frequency sweep linearization method by iterative learning pre-distortion for frequency-modulated continuous-wave (FMCW) light detection and ranging (LiDAR) systems. A pre-distorted laser drive voltage waveform that results in a linear frequency sweep is obtained by an iterative learning controller, and then applied to the FMCW LiDAR system. We have also derived a fundamental figure of merit for the maximum residual nonlinearity needed to achieve the transform-limited range resolution. This method is experimentally tested using a commercial vertical cavity surface-emitting laser (VCSEL) and a distributed feedback (DFB) laser, achieving less than 0.005% relative residual nonlinearity of frequency sweep. With the proposed method, high-performance FMCW LiDAR systems can be realized without expensive linear lasers, complex linearization setups, or heavy post-processing.

Graphene-based polarization-sensitive longwave infrared photodetector.

We demonstrated a polarization-sensitive photodetector based on periodically crossed graphene ribbons theoretically. Localized surface plasmon is generated by patterned graphene structure with significantly enhanced incident light absorption. Broadband detection is observed from 10.5 to 16.5 µm. Moreover, the photoresponsivity reaches up to 1.717 A W-1 at the wavelength of 12.58 µm under 0° polarization, and the photoresponsivity is 0.212 A W-1 under 90° polarization. The tunability of photodetectors is achieved by changing the gate voltage to modulate the chemical potential of graphene. The finite difference time domain solutions are used to predict the performance of the photodetector with different polarization angles for longwave infrared (LWIR) light. The polarization-sensitive, tunable and broadband graphene photodetector provides a promising direction for high performance LWIR detection at room temperature.

Effects of recipient oocyte source, number of transferred embryos and season on somatic cell nuclear transfer efficiency in sheep.

To improve the efficiency of somatic cell nuclear transfer (SCNT) in sheep, we investigated the effects of recipient oocyte source, number of transferred embryos and season on the pregnancy and live lamb rates for sheep somatic cell nuclear transfer embryos. Follicle-stimulating hormone (FSH)-stimulated ovaries produced significantly more oocytes both in total and of suitable quality for maturation culture than those without FSH treatment (from slaughterhouse). However, their in vitro maturation rates were similar. Embryos were reconstructed using adult fibroblast cells into enucleated MII oocytes. The pregnancy and term rates were significantly higher in the FSH-stimulated group than in the slaughterhouse one. Oocytes from FSH-stimulated ovaries were enucleated as recipient cytoplasm for nuclear transfer in the following experiments. The transfer of 7-9 and 11-13 embryos produced significantly higher pregnancy rates than that of six embryos. However, the former groups exhibited similar live lamb rates. FSH-stimulated ovaries produced significantly more oocytes in November and December (winter) than in May to July (summer), but the associated maturation rate did not increase. Pregnancy and term rates were significantly higher when transfer occurred in winter than in summer. In conclusion, FSH treatment produced significant benefit regarding the number and quality of collected oocytes and also for the pregnancy and live lamb rates for reconstructed embryos. However, the transfer of an appropriate number of embryos (7-13) and at an appropriate season (winter) increased pregnancy and term rates.

Overexpression of Toll-Like Receptor 4 Contributes to Phagocytosis of Salmonella Enterica Serovar Typhimurium via Phosphoinositide 3-Kinase Signaling in Sheep.

BACKGROUND/AIMS: Phagocytosis of bacteria by monocytes/macrophages can trigger the immune response and the clearance of bacteria. This innate immune response involves Toll-like receptor 4 (TLR4). However, much remains unknown about the mechanism of TLR4-regulated phagocytosis of Salmonella enterica serovar Typhimurium (S. typhimurium) within sheep monocytes/macrophages. Here, we aimed to address these knowledge gaps by infecting transgenic sheep overexpressing TLR4 with S. typhimurium and examining the phagocytic mechanisms involved. METHODS: Transgenic sheep were generated by microinjection of the constructed plasmids into fertilized eggs. Monocytes/macrophages isolated from sheep blood were stimulated with LPS and S. typhimurium. Phagocytosis-related factor expression, phagocytic ability, and adhesion were then determined. TLR4/phosphatidylinositide 3-kinase (PI3K) signaling was inhibited to investigate if this pathway is involved in changes in bacterial internalization in sheep. RESULTS: We found that TLR4 overexpression effectively activated the PI3K signaling pathway and upregulated the expression of scavenger receptors. Additionally, actin polymerization and adhesive capacity were both enhanced in TLR4-overexpressing sheep monocytes/macrophages. TLR4 inhibition decreased S. typhimurium phagocytosis by reducing the actin polymerization and adhesive capacity of cells. Furthermore, inhibition of PI3K markedly impaired TLR4-dependent phagocytosis by restraining actin polymerization and scavenger receptor expression and reduced the adhesive capacity of the monocytes/macrophages. CONCLUSION: Our findings indicate that overexpression of TLR4 enhances phagocytosis through PI3K signaling and the subsequent activation of actin polymerization and scavenger receptors in sheep monocytes/macrophages infected with S. typhimurium.

Self-referenced octave-wide subharmonic GaP optical parametric oscillator centered at 3 µm and pumped by an Er-fiber laser: erratum.

This erratum reports a correction to the labeling of Figs. 2(b) and 3(b) in the original manuscript, Opt. Lett.42, 4756 (2017)OPLEDP0146-959210.1364/OL.42.004756.

Metabolic Effects of FecB Gene on Follicular Fluid and Ovarian Vein Serum in Sheep (Ovis aries).

The FecB gene has been discovered as an important gene in sheep for its high relationship with the ovulation rate, but its regulatory mechanism remains unknown. In the present study, liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) techniques were adopted to detect the metabolic effects of FecB gene in follicular fluid (FF) and ovarian vein serum (OVS) in Small Tail Han (STH) sheep. ANOVA and random forest statistical methods were employed for the identification of important metabolic pathways and biomarkers. Changes in amino acid metabolism, redox environment, and energy metabolism were observed in FF from the three FecB genotype STH ewes. Principal component analysis (PCA) and hierarchical clustering analysis (HCA) showed that metabolic effects of FecB gene are more pronounced in FF than in OVS. Therefore, the difference of the metabolic profile in FF is also affected by the FecB genotypes. In Spearman correlation analysis, key metabolites (e.g., glucose 6-phosphate, glucose 1-phosphate, aspartate, asparagine, glutathione oxidized (GSSG), cysteine-glutathione disulfide, γ-glutamylglutamine, and 2-hydrosybutyrate) in ovine FF samples showed a significant correlation with the ovulation rate. Our findings will help to explain the metabolic mechanism of high prolificacy ewes and benefit fertility identification.

Melatonin-Mediated Development of Ovine Cumulus Cells, Perhaps by Regulation of DNA Methylation.

Cumulus cells of pre-pubertal domestic animals are dysfunctional, perhaps due to age-specific epigenetic events. This study was designed to determine effects of melatonin treatment of donors on methylation modification of pre-pubertal cumulus cells. Cumulus cells from germinal vesicle stage cumulus oocyte complexes (COCs) were collected from eighteen lambs which were randomly divided into control group (C) and melatonin group given an 18 mg melatonin implant subcutaneous (M). Compared to the C group, the M group had higher concentrations of melatonin in plasma and follicular fluid (p < 0.05), greater superovulation, a higher proportion of fully expanded COCs, and a lower proportion of apoptotic cumulus cells (p < 0.05). Real-time PCR results showed that melatonin up-regulated expression of genes MT1, Bcl2, DNMT1, DNMT3a and DNMT3b, but down-regulated expression of genes p53, Caspase 3 and Bax (p < 0.05). Furthermore, melatonin increased FI of FITC (global methylation level) on cumulus cells (p < 0.05). To understand the regulation mechanism, the DNMTs promoter methylation sequence were analyzed. Compared to the C group, although there was less methylation at two CpG sites of DNMT1 (p < 0.05) and higher methylation at two CpG sites of DNMT3a (p < 0.05), there were no significant differences in methylation of the detected DNMT1 and DNMT3a promoter regions. However, there were lower methylation levels at five CpG sites of DNMT3b, which decreased methylation of detected DNMT3b promoter region on M group (p < 0.05). In conclusion, alterations of methylation regulated by melatonin may mediate development of cumulus cells in lambs.