a-conditioned-place-preference-protocol-for-measuring-incubation

A Conditioned Place Preference Protocol for Measuring Incubation of Craving in Rats

A major cause of repeated relapses is a craving for the drug. Drug craving increases progressively during the abstinence period, a phenomenon termed ...

Chinese Academy of Sciences

A facile strategy was developed to delicately control the morphologies of hydroxyapatite materials from simple 0D morphologies to complicated 3D architectures using hard-precursors with similar structures. The present study provides a new platform for hydroxyapatite materials to be efficiently synthesized and manipulated.

Facile synthesis of hydroxyapatite nanoparticles, nanowires and hollow nano-structured microspheres using similar structured hard-precursors.

Ascaris suum (large roundworm of pigs) is a parasitic nematode that causes substantial losses to the meat industry. This nematode is suitable for biochemical studies because, unlike C. elegans, homogeneous tissue samples can be obtained by dissection. It has large sperm, produced in great numbers that permit biochemical studies of sperm motility. Widespread study of A. suum would be facilitated by more comprehensive genome resources and, to this end, we have produced a gonad transcriptome of A. suum.

Comparative transcriptome sequencing of germline and somatic tissues of the Ascaris suum gonad.

Visual experience can cause functional modification in the adult visual cortex; however, how cortical receptive fields (RFs) are dynamically modified by natural scene stimulation remains unclear. Here, using in vivo patch-clamp recordings from neurons in the rat primary visual cortex (V1), we showed that minutes of conditioning with natural movies could increase the similarity between cortical RF structure and the subset of movie images that depolarized the cell. This effect lasted for a few minutes in the absence of further movie stimulation. Manipulating the statistics of the movies by temporal shuffling or spatial whitening showed that the spatiotemporal correlation of the movie was important in inducing the RF modification. Furthermore, the movie-induced RF modification required the activation of N-methyl-d-aspartate receptors. Such rapid RF modification may play an important role in the dynamic coding of natural scenes. 

Modification of visual cortical receptive field induced by natural stimuli.

Although sperm is transcriptionally and translationally quiescent, complex populations of RNAs, including mRNAs and non-coding RNAs, exist in sperm. Previous microarray analysis of germ cell mutants identified hundreds of sperm genes in Caenorhabditis elegans. To take a more comprehensive view on C. elegans sperm genes, here, we isolate highly pure sperm cells and employ high-throughput technologies to obtain sperm transcriptome and proteome.

Characterisation of Caenorhabditis elegans sperm transcriptome and proteome.

miR-27 plays a negative role in the regulation of adipogenesis. However, the molecular mechanism still remains to be clarified. In the present study, we found that miR-27 inhibits adipogenesis partially by repressing the early adipogenic transcription factor cAMP response element-binding protein by directly targeting its 3' untranslated region. In addition, we demonstrated that tumor necrosis factor-α (TNF-α) treatment up-regulates miR-27 through the NF-κB pathway. Furthermore, anti-miR-27 reduces the TNF-α-induced inhibition of adipogenesis. Simultaneously, the levels of miR-27 expression were decreased in mature adipocytes of obese mice when compared with lean mice. Our data revealed a novel mechanism of miR-27 in the regulation of adipogenesis.

miR-27 inhibits adipocyte differentiation via suppressing CREB expression.

The responses of visual cortical neurons to natural stimuli are both reliable and sparse. These properties require inhibition, yet the contribution of specific types of inhibitory neurons is not well understood. Here we demonstrate that optogenetic suppression of parvalbumin (PV)- but not somatostatin (SOM)-expressing interneurons reduces response reliability in the primary visual cortex of anaesthetized and awake mice. PV suppression leads to increases in the low firing rates and decreases in the high firing rates of cortical neurons, resulting in an overall reduction of the signal-to-noise ratio (SNR). In contrast, SOM suppression generally increases the overall firing rate for most neurons, without affecting the SNR. Further analysis reveals that PV, but not SOM, suppression impairs neural discrimination of natural stimuli. Together, these results reveal a critical role for PV interneurons in the formation of reliable visual cortical representations of natural stimuli. 

Control of response reliability by parvalbumin-expressing interneurons in visual cortex.

Danshen, Salvia miltiorrhiza Bunge, is one of the most widely used herbs in traditional Chinese medicine, wherein its rhizome/roots are particularly valued. The corresponding bioactive components include the tanshinone diterpenoids, the biosynthesis of which is a subject of considerable interest. Previous investigations of the S. miltiorrhiza transcriptome have relied on short-read next-generation sequencing (NGS) technology, and the vast majority of the resulting isotigs do not represent full-length cDNA sequences. Moreover, these efforts have been targeted at either whole plants or hairy root cultures. Here, we demonstrate that the tanshinone pigments are produced and accumulate in the root periderm, and apply a combination of NGS and single-molecule real-time (SMRT) sequencing to various root tissues, particularly including the periderm, to provide a more complete view of the S. miltiorrhiza transcriptome, with further insight into tanshinone biosynthesis as well. In addition, the use of SMRT long-read sequencing offered the ability to examine alternative splicing, which was found to occur in approximately 40% of the detected gene loci, including several involved in isoprenoid/terpenoid metabolism. 

Full-length transcriptome sequences and splice variants obtained by a combination of sequencing platforms applied to different root tissues of Salvia miltiorrhiza and tanshinone biosynthesis.

Analysis of the Genome Sequence of the Medicinal Plant Salvia miltiorrhiza.

A core-shell structured selenium@carbon composite material was obtained by a facile one-step microwave synthesis method. The uniform carbon shells coated on selenium spheres greatly minimized the shuttle effect of Li-Se cells. The morphology analysis of the cathodes after different cycles revealed that the Se cores were perfectly confined inside the unbroken C shells all through the 100 cycles. 

One-step microwave synthesized core-shell structured selenium@carbon spheres as cathode materials for rechargeable lithium batteries.

Differentiation of 3T3-L1 cells into adipocytes involves a highly-orchestrated series of events including contact inhibition (CI), clonal expansion, growth arrest, and terminal differentiation. Recent study demonstrated that 3T3-L1 preadipocytes will not be differentiated into mature adipocytes without CI stage, which indicated that CI stage plays an important role during 3T3-L1 adipogenesis. However, the molecular mechanism is not yet fully understood. In the present study, we found that the expression level of miR-29a/b/c was decreased and the expression of DNMT3A was up-regulated during CI stage, respectively. Furthermore, overexpression of miR-29a/b/c during CI stage inhibits adipogenesis significantly but not at other stages. In addition, miR-29a/b/c repressed DNMT3A expression by directly targeting its 3' untranslated region (3' UTR). Our data reveal a novel mechanism of miR-29a/b/c in the regulation of adipogenesis.

Downregulated miR-29a/b/c during Contact Inhibition Stage Promote 3T3-L1 Adipogenesis by Targeting DNMT3A.

Although much is known about transcriptional networks that control embryonic stem cell (ESC) self-renewal and differentiation, the metabolic regulation of ESC is less clear. Autophagy is a catabolic process that is activated under both stress and normal conditions to degrade damaged organelles and aggregated proteins, and thus plays pivotal roles in somatic and adult stem cell function. However, if and how ESCs harness autophagy to regulate stemness remains largely unknown. Recently, we have defined that autophagy is essential for mitochondrial homeostasis regulation in pluripotency acquirement and maintenance. Here we identified high autophagic flux as an essential mechanism to maintain ESC identity. We show that mouse ESCs exhibit a high autophagic flux that is maintained by coordinating expression of autophagy core molecular machinery genes through FOXO1, a forkhead family transcription factor. Tapering autophagic flux by manipulating either Atg3 or Foxo1 expression compromised ESC self-renewal, pluripotency, and differentiation that could be restored by gain of wild-type but not function-deficient Atg3 or Foxo1 mutants, respectively. Our results define a newly recognized role of autophagic flux in mouse ESC identity maintenance that links cellular catabolism to ESC fate regulation.

High autophagic flux guards ESC identity through coordinating autophagy machinery gene program by FOXO1.

Ginseng, which contains ginsenosides as bioactive compounds, has been regarded as an important traditional medicine for several millennia. However, the genetic background of ginseng remains poorly understood, partly because of the plant's large and complex genome composition. We report the entire genome sequence of Panax ginseng using next-generation sequencing. The 3.5-Gb nucleotide sequence contains more than 60% repeats and encodes 42 006 predicted genes. Twenty-two transcriptome datasets and mass spectrometry images of ginseng roots were adopted to precisely quantify the functional genes. Thirty-one genes were identified to be involved in the mevalonic acid pathway. Eight of these genes were annotated as 3-hydroxy-3-methylglutaryl-CoA reductases, which displayed diverse structures and expression characteristics. A total of 225 UDP-glycosyltransferases (UGTs) were identified, and these UGTs accounted for one of the largest gene families of ginseng. Tandem repeats contributed to the duplication and divergence of UGTs. Molecular modeling of UGTs in the 71st, 74th, and 94th families revealed a regiospecific conserved motif located at the N-terminus. Molecular docking predicted that this motif captures ginsenoside precursors. The ginseng genome represents a valuable resource for understanding and improving the breeding, cultivation, and synthesis biology of this key herb.

Panax ginseng genome examination for ginsenoside biosynthesis.

The salience of behaviorally relevant stimuli is dynamic and influenced by internal state and external environment. Monitoring such changes is critical for effective learning and flexible behavior, but the neuronal substrate for tracking the dynamics of stimulus salience is obscure. We found that neurons in the paraventricular thalamus (PVT) are robustly activated by a variety of behaviorally relevant events, including novel ("unfamiliar") stimuli, reinforcing stimuli and their predicting cues, as well as omission of the expected reward. PVT responses are scaled with stimulus intensity and modulated by changes in homeostatic state or behavioral context. Inhibition of the PVT responses suppresses appetitive or aversive associative learning and reward extinction. Our findings demonstrate that the PVT gates associative learning by providing a dynamic representation of stimulus salience.

Yingjie Zhu

Brain Cognition and Brain Disease Institute,
Shenzhen Institutes of Advanced Technology,
Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology

Chinese Academy of Sciences

A Conditioned Place Preference Protocol for Measuring Incubation of Craving in Rats

Yingjie Zhu

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Brain Cognition and Brain Disease Institute,Shenzhen Institutes of Advanced Technology,Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology

Chinese Academy of Sciences

A Conditioned Place Preference Protocol for Measuring Incubation of Craving in Rats

Brain Cognition and Brain Disease Institute,
Shenzhen Institutes of Advanced Technology,
Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology