DELLA-Mediated Gibberellin Acid Participation in the Regulation of Dormancy and Growth of <i>Fraxinus mandshurica</i> Rupr.

In Fraxinus mandshurica Rupr. (F. mandshurica), the mature seeds exhibit a deep dormancy trait, and the seedlings are vulnerable to external environmental factors, such as low temperature and drought, leading to ecological dormancy. In order to investigate the role of FmDELLA in growth and development, the variation in FmDELLA transcriptional level, the endogenous hormone content in seed germination and bud dormancy release, and the effects of the month, organs, and exogenous hormones on FmDELLA were determined. The results showed that FmDELLA genes had a synergistic impact with the XERICO, PP2C, and DOG genes on regulating hypocotyl elongation during seed germination. Unlike growing buds, the dormant buds had much higher levels of FmDELLA transcripts. Still, these transcript levels were lowered by using 100 mg/L exogenous gibberellin acid (GA), which could promote bud dormancy release. Exogenous hormones regulated the transcription of FmDELLA, which primarily occurred in the stems, leaves, buds, and flowers and reached its lowest level in September. The transition from dormancy to germination for buds and seeds was related to increased GA, auxin, and cytokinin and decreased abscisic acid. In conclusion, our study revealed the role of FmDELLA in the seed germination and release of bud dormancy and provided a solid basis for F. mandshurica tissue culture and micropropagation

Effects of Hormones and Epigenetic Regulation on the Callus and Adventitious Bud Induction of Fraxinus mandshurica Rupr.

Fraxinus mandshurica Rupr. (hereafter &ldquo;F. mandshurica&rdquo;) is known as one of northeast China&prime;s important, valuable hardwood timber species. However, tissue culture and micropropagation of the species are difficult and have low efficiency, limiting asexual propagation. In this manuscript, stem explants were utilized to establish an effective regeneration system through adventitious bud organogenesis. The factors influencing callus regeneration in vitro were determined, and callus regeneration technology was established. The mechanism of adventitious bud formation was analyzed. Thidiazuron (TDZ) played a crucial role in the formation of adventitious buds. Elevated concentrations of TDZ were beneficial to callus induction and low concentrations of 6-benzyladenine (BA) led to loose state callus formation. The order of callus induction rates for different explants was stem cotyledon (100%) &gt; segment (98.54%) &gt; hypocotyl (92.56%) &gt; root (50.71%). The effects of exogenous addition of 6-BA and TDZ on the endogenous hormone content of plants during the regeneration of adventitious buds were also assessed, as well as the expression characteristics of genes related to the regeneration pathway. The comprehensive analysis results showed that the suitable medium for callus induction and adventitious bud differentiation was c12 medium (MSB5 + 30 g/L sucrose + 7 g/L Agar + 5 mg/L 6-BA + 8 mg/L TDZ + 2 mg/L glycine + 0.1 mg/L IBA + 5% coconut water). The induction rates of callus and adventitious buds were 99.15% and 33.33%. The addition of 2.4 mg/L of the DNA demethylation reagent 5-azacytidine (5-aza) and 0.15 mg/L of the histone deacetylase inhibitor trichostatin A (TSA) increased the rates of adventitious bud induction by 17.78% over the control. This further laid the foundation for large-scale cultivation of excellent varieties and genetic transformation techniques

An Asp7Gly substitution in PPARG is associated with decreased transcriptional activation activity.

As the master regulator of adipogenesis, peroxisome proliferator-activated receptor gamma (PPARG) is required for the accumulation of adipose tissue and hence contributes to obesity. A previous study showed that the substitution of +20A>G in PPARG changed the 7(th) amino acid from Asp to Gly, creating a mutant referred to as PPARG Asp7Gly. In this study, association analysis indicated that PPARG Asp7Gly was associated with lower body height, body weight and heart girth in cattle (P<0.05). Overexpression of PPARG in NIH3T3-L1 cells showed that the Asp7Gly substitution may cause a decrease in its adipogenic ability and the mRNA levels of CIDEC (cell death-inducing DFFA-like effector c) and aP2, which are all transcriptionally activated by PPARG during adipocyte differentiation. A dual-luciferase reporter assay was used to analyze the promoter activity of CIDEC. The results confirmed that the mutant PPARG exhibited weaker transcriptional activation activity than the wild type (P<0.05). These findings likely explain the associations between the Asp7Gly substitution and the body measurements. Additionally, the Asp7Gly mutation may be used in molecular marker assisted selection (MAS) of cattle breeding in the future

Design and Synthesis of an MOF Thermometer with High Sensitivity in the Physiological Temperature Range

An important result of research on mixed-lanthanide metal–organic frameworks (M′LnMOFs) is the realization of highly sensitive ratiometric luminescent thermometers. Here, we report the design and synthesis of the new M′LnMOF Tb_0.80Eu_0.20BPDA with high relative sensitivity in the physiological temperature regime (298–318 K). The emission intensity and luminescence lifetime were investigated and compared to those of existing materials. It was found that the temperature-dependent luminescence properties of Tb_0.80Eu_0.20BPDA are strongly associated with the distribution of the energy levels of the ligand. Such a property can be useful in the design of highly sensitive M′LnMOF thermometers

Comparing the Effects of N and P Deficiency on Physiology and Growth for Fast- and Slow-Growing Provenances of <i>Fraxinus mandshurica</i>

With the continuous increase in atmospheric carbon dioxide emissions, nitrogen (N) and phosphorus (P) as mineral elements increasingly restrict plant growth. To explore the effect of deficiency of P and N on growth and physiology, Fraxinus mandshurica (hereafter “F. mandshurica”) Rupr. annual seedlings of Wuchang (WC) provenance with fast growth and Dailing (DL) provenance with slow growth were treated with complete nutrition or starvation of N (N-), P (P-) or both elements (NP-). Although P- and N- increased the use efficiency of P (PUE) and N (NUE), respectively, they reduced the leaf area, chlorophyll content and activities of N assimilation enzymes (NR, GS, GOGAT), which decreased the dry weight and P or N amount. The free amino acid content and activities of Phosphoenolpyruvate carboxylase (PEPC) and acid phosphatase enzymes were reduced by N-. The transcript levels of NRT2.1, NRT2.4, NRT2.5, NRT2.7, AVT1, AAP3, NIA2, PHT1-3, PHT1-4 and PHT2-1 in roots were increased, but those of NRT2.1, NRT2.4, NRT2.5, PHT1-3, PHT1-4, PHT2-1 and AAP3 in leaves were reduced by P-. WC was significantly greater than DL under P- in dry weight, C amount, N amount, leaf area, PUE, NUE, which related to greater chlorophyll content, PEPC enzyme activity, N assimilation enzyme activities, and transcript levels of N and P transporter genes in roots and foliage, indicating a greater ability of WC to absorb, transport and utilize N and P under P-. WC was also greater than DL under N- in terms of the above indicators except the transcript levels of N and P assimilation genes, but most of the indicators did not reach a significant level, indicating that WC might be more tolerant to N- than DL, which requires further verification. In summary, WC was identified as a P-efficient provenance, as the growth rate was greater for the genetic type with high than low tolerance to P-

Comparing the Effects of N and P Deficiency on Physiology and Growth for Fast- and Slow-Growing Provenances of Fraxinus mandshurica

With the continuous increase in atmospheric carbon dioxide emissions, nitrogen (N) and phosphorus (P) as mineral elements increasingly restrict plant growth. To explore the effect of deficiency of P and N on growth and physiology, Fraxinus mandshurica (hereafter &ldquo;F. mandshurica&rdquo;) Rupr. annual seedlings of Wuchang (WC) provenance with fast growth and Dailing (DL) provenance with slow growth were treated with complete nutrition or starvation of N (N-), P (P-) or both elements (NP-). Although P- and N- increased the use efficiency of P (PUE) and N (NUE), respectively, they reduced the leaf area, chlorophyll content and activities of N assimilation enzymes (NR, GS, GOGAT), which decreased the dry weight and P or N amount. The free amino acid content and activities of Phosphoenolpyruvate carboxylase (PEPC) and acid phosphatase enzymes were reduced by N-. The transcript levels of NRT2.1, NRT2.4, NRT2.5, NRT2.7, AVT1, AAP3, NIA2, PHT1-3, PHT1-4 and PHT2-1 in roots were increased, but those of NRT2.1, NRT2.4, NRT2.5, PHT1-3, PHT1-4, PHT2-1 and AAP3 in leaves were reduced by P-. WC was significantly greater than DL under P- in dry weight, C amount, N amount, leaf area, PUE, NUE, which related to greater chlorophyll content, PEPC enzyme activity, N assimilation enzyme activities, and transcript levels of N and P transporter genes in roots and foliage, indicating a greater ability of WC to absorb, transport and utilize N and P under P-. WC was also greater than DL under N- in terms of the above indicators except the transcript levels of N and P assimilation genes, but most of the indicators did not reach a significant level, indicating that WC might be more tolerant to N- than DL, which requires further verification. In summary, WC was identified as a P-efficient provenance, as the growth rate was greater for the genetic type with high than low tolerance to P-

Transcriptome Analysis for Fraxinus mandshurica Rupr. Seedlings from Different Carbon Sequestration Provenances in Response to Nitrogen Deficiency

To explore the molecular regulatory mechanism of high-carbon (C) sequestration Fraxinus mandshurica Rupr. (F. mandshurica) provenance and the expression profile of F. mandshurica during nitrogen (N) starvation, the foliage and roots of the annual Wuchang (WC) seedlings with greater C amount and Hailin (HL) seedlings with smaller C amount, which were grown in N-deficient nutrition and complete N, were used for RNA-seq and physiological determination, respectively. One thousand and fifty-seven differentially expressed genes (DEGs) between WC and HL and 8173 DEGs related to N deficiency were identified, respectively. The root of F. mandshurica responded to N deficiency more strongly than foliar. The target genes that responded to N deficiency in roots were mainly regulatory genes (transcription factors, hormones and protein kinases), and their response patterns were upregulated. The growth and N concentration in both WC and HL were reduced by the N deficiency, which might result from the decrease of the leaf Nitrate reductase (NR) and glutamine synthetase (GS) enzyme activity and ABA content, although the root-to-shoot ratio; lateral root number; lignin content; endogenous hormones content (GA, IAA and ZR); root GS and glutamate synthetase activity and transcriptional level of most of the regulatory genes were increased. The C sequestration capacity in WC was greater than that in HL, which related to the higher GS enzymes activity and transcriptional levels of regulatory genes and metabolic genes (terpenes, carbohydrates, and lipid energy). However, the C sequestration advantage of WC was significantly reduced by the N deficiency, which was due to the smaller response to N deficiency compared to HL

Transcriptome Analysis for <i>Fraxinus mandshurica</i> Rupr. Seedlings from Different Carbon Sequestration Provenances in Response to Nitrogen Deficiency

To explore the molecular regulatory mechanism of high-carbon (C) sequestration Fraxinus mandshurica Rupr. (F. mandshurica) provenance and the expression profile of F. mandshurica during nitrogen (N) starvation, the foliage and roots of the annual Wuchang (WC) seedlings with greater C amount and Hailin (HL) seedlings with smaller C amount, which were grown in N-deficient nutrition and complete N, were used for RNA-seq and physiological determination, respectively. One thousand and fifty-seven differentially expressed genes (DEGs) between WC and HL and 8173 DEGs related to N deficiency were identified, respectively. The root of F. mandshurica responded to N deficiency more strongly than foliar. The target genes that responded to N deficiency in roots were mainly regulatory genes (transcription factors, hormones and protein kinases), and their response patterns were upregulated. The growth and N concentration in both WC and HL were reduced by the N deficiency, which might result from the decrease of the leaf Nitrate reductase (NR) and glutamine synthetase (GS) enzyme activity and ABA content, although the root-to-shoot ratio; lateral root number; lignin content; endogenous hormones content (GA, IAA and ZR); root GS and glutamate synthetase activity and transcriptional level of most of the regulatory genes were increased. The C sequestration capacity in WC was greater than that in HL, which related to the higher GS enzymes activity and transcriptional levels of regulatory genes and metabolic genes (terpenes, carbohydrates, and lipid energy). However, the C sequestration advantage of WC was significantly reduced by the N deficiency, which was due to the smaller response to N deficiency compared to HL

Identification and Profiling of microRNAs and Their Target Genes from Developing Caprine Skeletal Muscle

<div><p>Goat is an important agricultural animal for meat production. Functional studies have demonstrated that microRNAs (miRNAs) regulate gene expression at the post-transcriptional level and play an important role in various biological processes. Although studies on miRNAs expression profiles have been performed in various animals, relatively limited information about goat muscle miRNAs has been reported. To investigate the miRNAs involved in regulating different periods of skeletal muscle development, we herein performed a comprehensive research for expression profiles of caprine miRNAs during two developmental stages of skeletal muscles: fetal stage and six month-old stage. As a result, 15,627,457 and 15,593,721 clean reads were obtained from the fetal goat library (FC) and the six month old goat library (SMC), respectively. 464 known miRNAs and 83 novel miRNA candidates were identified. Furthermore, by comparing the miRNA profile, 336 differentially expressed miRNAs were identified and then the potential targets of the differentially expressed miRNAs were predicted. To understand the regulatory network of miRNAs during muscle development, the mRNA expression profiles for the two development stages were characterized and 7322 differentially expressed genes (DEGs) were identified. Then the potential targets of miRNAs were compared to the DEGs, the intersection of the two gene sets were screened out and called differentially expressed targets (DE-targets), which were involved in 231 pathways. Ten of the 231 pathways that have smallest <i>P</i>-value were shown as network figures. Based on the analysis of pathways and networks, we found that miR-424-5p and miR-29a might have important regulatory effect on muscle development, which needed to be further studied. This study provided the first global view of the miRNAs in caprine muscle tissues. Our results help elucidation of complex regulatory networks between miRNAs and mRNAs and for the study of muscle development.</p></div

Analysis of <i>CIDEC</i> promoter activity driven by PPARG.

<p>A dual-luciferase reporter assay was used to detect the promoter activity of CIDEC driven by PPARG. The results obtained with the pGL3-basic and pGL3-control groups indicated that the dual-luciferase reporter assay was functional. The <i>CIDEC</i> promoter processes weak promoter activity in NIH3T3-L1 cells, and its activity was increased by the overexpression of PPARG (<i>P</i><0.01). Although both wild type and mutant PPARG are able to initiate the expression of CIDEC, the Asp7Gly mutation decreased the transcriptional activation activity of PPARG significantly (<i>P</i><0.05).</p