The thermal dependence and molecular basis of physiological color change in Takydromus septentrionalis (Lacertidae)

One of the main functions of physiological color change is thermoregulation. This change occurs much more rapidly than morphological color change, but the underlying mechanism remains poorly understood. Here, we studied the thermal dependence and molecular basis of physiological color change in lizards using Takydromus septentrionalis (Lacertidae) as the model system. Body color was thermally sensitive, becoming increasingly light as body temperatures deviated from the level (∼30 °C) preferred by this species. We identified 3,389 differentially expressed genes (DEGs) between lizards at 24 °C and 30 °C, and 1,097 DEGs between lizards at 36 °C and 30 °C. Temperature affected the cAMP signal pathway, motor proteins, cytoskeleton, and the expression of genes related to melanocyte-stimulating hormone (MSH) and melanocyte-concentrating hormone (MCH). Our data suggest that the role of physiological color change in thermoregulation is achieved in T. septentrionalis by altering the arrangement of pigments and thus the amount of solar radiation absorbed and reflected. G protein-coupling system inhibits adenylate cyclase activity to transform ATP into cAMP and thereby causes rapid pigment aggregation. MCH deactivates the G proteins and thereby initiates pigment dispersion. This mechanism differs from that reported for teleost fish where MCH activates the G proteins and thereby causes pigment aggregation.

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First person – Kun Guo

Biology Open ◽

10.1242/bio.058650 ◽

2021 ◽

Vol 10 (3) ◽

Keyword(s):

Color Change ◽

Life Sciences ◽

Early Career ◽

First Person ◽

Research Assistant ◽

Thermal Dependence ◽

Early Career Researchers ◽

Takydromus Septentrionalis ◽

Normal University ◽

Selection Of

ABSTRACT First Person is a series of interviews with the first authors of a selection of papers published in Biology Open, helping early-career researchers promote themselves alongside their papers. Kun Guo is first author on ‘The thermal dependence and molecular basis of physiological color change in Takydromus septentrionalis (Lacertidae)’, published in BiO. Kun conducted the research described in this article while a PhD student in Xiang Ji's lab at Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Jiangsu, China. They are now research assistant in the lab of Xiang Ji at College of Life and Environmental Sciences, Wenzhou University, Zhejiang, China, and Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu, China.

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Dynamic histone acetylation in floral volatile synthesis and emission in petunia flowers

Journal of Experimental Botany ◽

10.1093/jxb/erab072 ◽

2021 ◽

Author(s):

Ryan M Patrick ◽

Xing-Qi Huang ◽

Natalia Dudareva ◽

Ying Li

Keyword(s):

Transcriptional Activation ◽

Metabolic Pathways ◽

Transcriptional Repression ◽

Metabolic Networks ◽

Underlying Mechanism ◽

Expression Of Genes ◽

Genome Wide ◽

Chemical Inhibitors ◽

Volatile Organic ◽

Floral Volatile

Abstract Biosynthesis of secondary metabolites relies on primary metabolic pathways to provide precursors, energy, and cofactors, thus requiring coordinated regulation of primary and secondary metabolic networks. However, to date, it remains largely unknown how this coordination is achieved. Using Petunia hybrida flowers, which emit high levels of phenylpropanoid/benzenoid volatile organic compounds (VOCs), we uncovered genome-wide dynamic deposition of histone H3 lysine 9 acetylation (H3K9ac) during anthesis as an underlying mechanism to coordinate primary and secondary metabolic networks. The observed epigenome reprogramming is accompanied by transcriptional activation at gene loci involved in primary metabolic pathways that provide precursor phenylalanine, as well as secondary metabolic pathways to produce volatile compounds. We also observed transcriptional repression among genes involved in alternative phenylpropanoid branches that compete for metabolic precursors. We show that GNAT family histone acetyltransferase(s) (HATs) are required for the expression of genes involved in VOC biosynthesis and emission, by using chemical inhibitors of HATs, and by knocking down a specific HAT gene, ELP3, through transient RNAi. Together, our study supports that regulatory mechanisms at chromatin level may play an essential role in activating primary and secondary metabolic pathways to regulate VOC synthesis in petunia flowers.

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Transcriptomic analysis of the cardiac left ventricle in a rodent model of diabetic cardiomyopathy: molecular snapshot of a severe myocardial disease

Physiological Genomics ◽

10.1152/physiolgenomics.00204.2006 ◽

2007 ◽

Vol 28 (3) ◽

pp. 284-293 ◽

Cited By ~ 19

Author(s):

Sarah Glyn-Jones ◽

Sarah Song ◽

Michael A. Black ◽

Anthony R. J. Phillips ◽

Soon Y. Choong ◽

...

Keyword(s):

Diabetic Cardiomyopathy ◽

Molecular Basis ◽

Cardiovascular Complications ◽

Left Ventricular ◽

Myocardial Disease ◽

Chronic Hyperglycemia ◽

Expression Of Genes ◽

Streptozotocin Induced Diabetes ◽

Quantitative Verification ◽

Disproportionate Number

Heart disease is the major cause of death in diabetes, a disorder characterized by chronic hyperglycemia and cardiovascular complications. Diabetic cardiomyopathy (DCM) is increasingly recognized as a major contributor to diastolic dysfunction and heart failure in diabetes, but its molecular basis has remained obscure, in part because of its multifactorial origins. Here we employed comparative transcriptomic methods with quantitative verification of selected transcripts by reverse transcriptase quantitative PCR to characterize the molecular basis of DCM in rats with streptozotocin-induced diabetes of 16-wk duration. Diabetes caused left ventricular disease that was accompanied by significant changes in the expression of 1,614 genes, 749 of which had functions assignable by Gene Ontology classification. Genes corresponding to proteins expressed in mitochondria accounted for a disproportionate number of those whose expression was significantly modified in DCM, consistent with the idea that the mitochondrion is a key target of the pathogenic processes that cause myocardial disease in diabetes. Diabetes also induced global perturbations in the expression of genes regulating cardiac fatty acid metabolism, whose dysfunction is likely to play a key role in the promotion of oxidative stress, thereby contributing to the pathogenesis of diabetic myocardial disease. In particular, these data point to impaired regulation of mitochondrial β-oxidation as central in the mechanisms that generate DCM pathogenesis. This study provides a comprehensive molecular snapshot of the processes leading to myocardial disease in diabetes.

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Ischemia of Rat Brain Decreases Pertussis Toxin-Catalyzed [32P]ADP Ribosylation of GTP-Binding Proteins (Gi1 and G0) in Membranes

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1991.19 ◽

1991 ◽

Vol 11 (1) ◽

pp. 155-160 ◽

Cited By ~ 5

Author(s):

Katsunobu Takenaka ◽

Yasunori Kanaho ◽

Koh-Ichi Nagata ◽

Noboru Sakai ◽

Hiromu Yamada ◽

...

Keyword(s):

Cerebral Cortex ◽

G Proteins ◽

Pertussis Toxin ◽

Molecular Basis ◽

Guanine Nucleotides ◽

Qualitative And Quantitative ◽

Adp Ribosylation ◽

Quantitative Changes ◽

Control Stimulation ◽

Stimulation Of

As an approach to understanding the molecular basis of the pathophysiology of cerebral ischemia, we examined qualitative and quantitative changes in pertussis toxin substrates, Gi1 and G0, in the membrane of rat cerebral cortex after decapitation. Within 1 min after decapitation, the extent of pertussis toxin-catalyzed [32P]ADP ribosylation of the G proteins in the cerebral cortex membrane was significantly decreased and the magnitude of the decrease became slightly larger upon further incubation of the decapitated brain. Addition of guanine nucleotides, GTP and GDP, or the purified βγ subunits of transducin to the membranes of control and ischemic cerebral cortex stimulated [32P]ADP ribosylation of the G proteins. The stimulation of [32P]ADP ribosylation in the control situation by guanine nucleotides was almost to the same extent as that in ischemia. However, the stimulation by transducin βγ subunits was different; the control stimulation was greater than that in ischemia. In immunoblots probed with antibodies against Gi1α G0α and Tβ, the immunoreactivity of the corresponding proteins in ischemia was similar to that in control, suggesting that the amounts of G proteins were not changed in ischemia. These results suggest that ischemia accelerates the dissociation of α–GDP–βγ to α–GDP and free βγ and causes the denaturation of the dissociated α–GDP, thereby decreasing [32P]ADP ribosylation.

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Molecular basis of resistance to organophosphate insecticides in the New World screw-worm fly

Parasites & Vectors ◽

10.1186/s13071-020-04433-3 ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Sophie Tandonnet ◽

Gisele Antoniazzi Cardoso ◽

Pedro Mariano-Martins ◽

Raquel Dietsche Monfardini ◽

Vanessa A. S. Cunha ◽

...

Keyword(s):

Insecticide Resistance ◽

Molecular Basis ◽

Pyrethroid Resistance ◽

Management Strategies ◽

Evolutionary Process ◽

Specific Expression ◽

Altered Expression ◽

Functional Studies ◽

Expression Of Genes ◽

Starting Point

Abstract Background The emergence of insecticide resistance is a fast-paced example of the evolutionary process of natural selection. In this study, we investigated the molecular basis of resistance in the myiasis-causing fly Cochliomyia hominivorax (Diptera: Calliphoridae) to dimethyl-organophosphate (OP) insecticides. Methods By sequencing the RNA from surviving larvae treated with dimethyl-OP (resistant condition) and non-treated larvae (control condition), we identified genes displaying condition-specific polymorphisms, as well as those differentially expressed. Results Both analyses revealed that resistant individuals have altered expression and allele-specific expression of genes involved in proteolysis (specifically serine-endopeptidase), olfactory perception and cuticle metabolism, among others. We also confirmed that resistant individuals carry almost invariably the Trp251Ser mutation in the esterase E3, known to confer OP and Pyrethroid resistance. Interestingly, genes involved in metabolic and detoxifying processes (notably cytochrome P450s) were found under-expressed in resistant individuals. An exception to this were esterases, which were found up-regulated. Conclusions These observations suggest that reduced penetration and aversion to dimethyl-OP contaminated food may be important complementary strategies of resistant individuals. The specific genes and processes found are an important starting point for future functional studies. Their role in insecticide resistance merits consideration to better the current pest management strategies.

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Hydrogen peroxide stimulates ubiquitin-conjugating activity and expression of genes for specific E2 and E3 proteins in skeletal muscle myotubes

AJP Cell Physiology ◽

10.1152/ajpcell.00129.2003 ◽

2003 ◽

Vol 285 (4) ◽

pp. C806-C812 ◽

Cited By ~ 226

Author(s):

Yi-Ping Li ◽

Yuling Chen ◽

Andrew S. Li ◽

Michael B. Reid

Keyword(s):

Skeletal Muscle ◽

Actinomycin D ◽

Underlying Mechanism ◽

Muscle Proteins ◽

Conjugation System ◽

Cell Extracts ◽

Expression Of Genes ◽

Ubiquitin Conjugation ◽

Muscle Catabolism ◽

Stimulation Of

Reactive oxygen species (ROS) are thought to promote muscle atrophy in chronic wasting diseases, but the underlying mechanism has not been determined. Here we show that H2O2 stimulates ubiquitin conjugation to muscle proteins through transcriptional regulation of the enzymes (E2 and E3 proteins) that conjugate ubiquitin to muscle proteins. Incubation of C2C12 myotubes with 100 μM H2O2 increased the rate of 125I-labeled ubiquitin conjugation to muscle proteins in whole cell extracts. This response required at least 4-h exposure to H2O2 and persisted for at least 24 h. Preincubating myotubes with cycloheximide or actinomycin D blocked H2O2 stimulation of ubiquitin-conjugating activity, suggesting that gene transcription is required. Northern blot analyses revealed that H2O2 upregulates expression of specific E3 and E2 proteins that are thought to regulate muscle catabolism, including atrogin1/MAFbx, MuRF1, and E214k. These results suggest that ROS stimulate protein catabolism in skeletal muscle by upregulating the ubiquitin conjugation system.

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Crtc modulates fasting programs associated with 1-C metabolism and inhibition of insulin signaling

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2024865118 ◽

2021 ◽

Vol 118 (12) ◽

pp. e2024865118

Author(s):

Tian Wang ◽

Ezra Wiater ◽

Xinmin Zhang ◽

John B. Thomas ◽

Marc Montminy

Keyword(s):

Insulin Signaling ◽

Binding Sites ◽

Target Genes ◽

Underlying Mechanism ◽

Starvation Response ◽

Expression Of Genes ◽

Adenosyl Methionine ◽

C Metabolism ◽

Inducible Genes ◽

And Oxidative Stress

Fasting in mammals promotes increases in circulating glucagon and decreases in circulating insulin that stimulate catabolic programs and facilitate a transition from glucose to lipid burning. The second messenger cAMP mediates effects of glucagon on fasting metabolism, in part by promoting the phosphorylation of CREB and the dephosphorylation of the cAMP-regulated transcriptional coactivators (CRTCs) in hepatocytes. In Drosophila, fasting also triggers activation of the single Crtc homolog in neurons, via the PKA-mediated phosphorylation and inhibition of salt-inducible kinases. Crtc mutant flies are more sensitive to starvation and oxidative stress, although the underlying mechanism remains unclear. Here we use RNA sequencing to identify Crtc target genes that are up-regulated in response to starvation. We found that Crtc stimulates a subset of fasting-inducible genes that have conserved CREB binding sites. In keeping with its role in the starvation response, Crtc was found to induce the expression of genes that inhibit insulin secretion (Lst) and insulin signaling (Impl2). In parallel, Crtc also promoted the expression of genes involved in one-carbon (1-C) metabolism. Within the 1-C pathway, Crtc stimulated the expression of enzymes that encode modulators of S-adenosyl-methionine metabolism (Gnmt and Sardh) and purine synthesis (ade2 and AdSl). Collectively, our results point to an important role for the CREB/CRTC pathway in promoting energy balance in the context of nutrient stress.

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Molecular basis of wax-based color change and UV reflection in dragonflies

eLife ◽

10.7554/elife.43045 ◽

2019 ◽

Vol 8 ◽

Cited By ~ 3

Author(s):

Ryo Futahashi ◽

Yumi Yamahama ◽

Migaku Kawaguchi ◽

Naoki Mori ◽

Daisuke Ishii ◽

...

Keyword(s):

Molecular Basis ◽

Color Change ◽

Biochemical Properties ◽

Methyl Ketones ◽

Body Color ◽

Fatty Acid Elongase ◽

Visual Signaling ◽

Fine Structures ◽

Uv Reflection ◽

Long Chain

Many animals change their body color for visual signaling and environmental adaptation. Some dragonflies show wax-based color change and ultraviolet (UV) reflection, but the biochemical properties underlying the phenomena are totally unknown. Here we investigated the UV-reflective abdominal wax of dragonflies, thereby identifying very long-chain methyl ketones and aldehydes as unique and major wax components. Little wax was detected on young adults, but dense wax secretion was found mainly on the dorsal abdomen of mature males of Orthetrum albistylum and O. melania, and pruinose wax secretion was identified on the ventral abdomen of mature females of O. albistylum and Sympetrum darwinianum. Comparative transcriptomics demonstrated drastic upregulation of the ELOVL17 gene, a member of the fatty acid elongase gene family, whose expression reflected the distribution of very long-chain methyl ketones. Synthetic 2-pentacosanone, the major component of dragonfly’s wax, spontaneously formed light-scattering scale-like fine structures with strong UV reflection, suggesting its potential utility for biomimetics.

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Melatonin Promotes SGT1-Involved Signals to Ameliorate Drought Stress Adaption in Rice

International Journal of Molecular Sciences ◽

10.3390/ijms23020599 ◽

2022 ◽

Vol 23 (2) ◽

pp. 599

Author(s):

Ruiqing Li ◽

Ruifang Yang ◽

Wenyin Zheng ◽

Liquan Wu ◽

Can Zhang ◽

...

Keyword(s):

Drought Stress ◽

Antioxidant System ◽

Survival Rates ◽

Foliar Spray ◽

Underlying Mechanism ◽

Severe Drought ◽

Environmental Threats ◽

Expression Of Genes ◽

Osmotic Balance ◽

Agriculture And Food

Drought has become one of the environmental threats to agriculture and food security. Applications of melatonin (MT) serve as an effective way to alleviate drought stress, but the underlying mechanism remains poorly understood. Here, we found that foliar spray of 100-µM MT greatly mitigated the severe drought stress-induced damages in rice seedlings, including improved survival rates, enhanced antioxidant system, and adjusted osmotic balance. However, mutation of the suppressor of the G2 allele of skp1 (OsSGT1) and ABSCISIC ACID INSENSITIVE 5 (OsABI5) abolished the effects of MT. Furthermore, the upregulated expression of OsABI5 was detected in wild type (WT) under drought stress, irrespective of MT treatment, whereas OsABI5 was significantly downregulated in sgt1 and sgt1abi5 mutants. In contrast, no change of the OsSGT1 expression level was detected in abi5. Moreover, mutation of OsSGT1 and OsABI5 significantly suppressed the expression of genes associated with the antioxidant system. These results suggested that the functions of OsSGT1 in the MT-mediated alleviation of drought stress were associated with the ABI5-mediated signals. Collectively, we demonstrated that OsSGT1 was involved in the drought response of rice and that melatonin promoted SGT1-involved signals to ameliorate drought stress adaption.

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Comparative Metabolomic Analysis Reveals Distinct Flavonoid Biosynthesis Regulation for Leaf Color Development of Cymbidium sinense ‘Red Sun’

International Journal of Molecular Sciences ◽

10.3390/ijms21051869 ◽

2020 ◽

Vol 21 (5) ◽

pp. 1869 ◽

Cited By ~ 1

Author(s):

Jie Gao ◽

Rui Ren ◽

Yonglu Wei ◽

Jianpeng Jin ◽

Sagheer Ahmad ◽

...

Keyword(s):

Enzyme Activities ◽

Biosynthetic Pathway ◽

Color Change ◽

Leaf Color ◽

Anthocyanin Biosynthetic Pathway ◽

Expression Of Genes ◽

Genes Expression ◽

Genes Encoding ◽

Changing Patterns ◽

Cymbidium Sinense

The colorful leaf is an important ornamental character of Cymbidium sinense (C. sinense), especially the red leaf, which has always been attracted by breeders and consumers. However, little is documented on the formation mechanism of the red leaf of C. sinense. In this study, the changing patterns of flavonoid-related metabolites, corresponding enzyme activities and genes expression in the leaves of C. sinense ‘Red Sun’ from red to yellow and finally to green was investigated. A total of 196 flavonoid-related metabolites including 11 anthocyanins metabolites were identified using UPLC-MS/MS-based approach. In the process of leaf color change, 42 metabolites were identified as having significantly different contents and the content of 28 differential metabolites turned to zero. In anthocyanin biosynthetic pathway, content of all 15 identified metabolites showed downregulation trend in the process of leaf color change. Among the 15 metabolites, the contents of Naringenin chalcone, Pelargonidin O-acetylhexoside and Anthocyanin 3-O-beta-d-glucoside decreased to zero in the green leaf stage. The changing pattern of enzyme activity of 10 enzymes involved in the anthocyanin biosynthetic pathway showed different trends from red leaves that have turned yellow and finally green, while the expression of genes encoding these enzymes was all down-regulated in the process of leaf color change. The results of this study revealed the types of flavonoid-related metabolites and the comprehensive analysis of metabolites content, enzyme activities and genes expression providing a new reference for breeders to improve the leaf color of C. sinense ‘Red Sun’.

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