scholarly journals Steroid hormone ecdysone deficiency stimulates preparation for photoperiodic reproductive diapause

PLoS Genetics ◽  
2021 ◽  
Vol 17 (2) ◽  
pp. e1009352
Author(s):  
Shuang Guo ◽  
Zhong Tian ◽  
Qing-Wen Wu ◽  
Kirst King-Jones ◽  
Wen Liu ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Steroid Hormone ◽  
Active Form ◽  
Reproductive Diapause ◽  
Fat Accumulation ◽  
Adverse Conditions ◽  
Long Day ◽  
Endocrine Factor ◽  
Ecdysis Triggering Hormone ◽  
Endocrine Signaling

Diapause, a programmed developmental arrest primarily induced by seasonal environmental changes, is very common in the animal kingdom, and found in vertebrates and invertebrates alike. Diapause provides an adaptive advantage to animals, as it increases the odds of surviving adverse conditions. In insects, individuals perceive photoperiodic cues and modify endocrine signaling to direct reproductive diapause traits, such as ovary arrest and increased fat accumulation. However, it remains unclear as to which endocrine factors are involved in this process and how they regulate the onset of reproductive diapause. Here, we found that the long day-mediated drop in the concentration of the steroid hormone ecdysone is essential for the preparation of photoperiodic reproductive diapause in Colaphellus bowringi, an economically important cabbage beetle. The diapause-inducing long-day condition reduced the expression of ecdysone biosynthetic genes, explaining the drop in the titer of 20-hydroxyecdysone (20E, the active form of ecdysone) in female adults. Application of exogenous 20E induced vitellogenesis and ovarian development but reduced fat accumulation in the diapause-destined females. Knocking down the ecdysone receptor (EcR) in females destined for reproduction blocked reproductive development and induced diapause traits. RNA-seq and hormone measurements indicated that 20E stimulates the production of juvenile hormone (JH), a key endocrine factor in reproductive diapause. To verify this, we depleted three ecdysone biosynthetic enzymes via RNAi, which confirmed that 20E is critical for JH biosynthesis and reproductive diapause. Importantly, impairing Met function, a component of the JH intracellular receptor, partially blocked the 20E-regulated reproductive diapause preparation, indicating that 20E regulates reproductive diapause in both JH-dependent and -independent manners. Finally, we found that 20E deficiency decreased ecdysis-triggering hormone signaling and reduced JH production, thereby inducing diapause. Together, these results suggest that 20E signaling is a pivotal regulator that coordinates reproductive plasticity in response to environmental inputs.

scholarly journals Gut Microbial Influences on the Mammalian Intestinal Stem Cell Niche

2017 ◽  
Vol 2017 ◽  
pp. 1-17 ◽  
Author(s):  
Bailey C. E. Peck ◽  
Michael T. Shanahan ◽  
Ajeet P. Singh ◽  
Praveen Sethupathy
Keyword(s):  
Stem Cell ◽  
Gut Microbiota ◽  
Energy Homeostasis ◽  
Environmental Changes ◽  
Intestinal Epithelial ◽  
Microbe Interactions ◽  
Host Microbe Interactions ◽  
Cell Niche ◽  
Systemic Health ◽  
Endocrine Signaling

The mammalian intestinal epithelial stem cell (IESC) niche is comprised of diverse epithelial, immune, and stromal cells, which together respond to environmental changes within the lumen and exert coordinated regulation of IESC behavior. There is growing appreciation for the role of the gut microbiota in modulating intestinal proliferation and differentiation, as well as other aspects of intestinal physiology. In this review, we evaluate the diverse roles of known niche cells in responding to gut microbiota and supporting IESCs. Furthermore, we discuss the potential mechanisms by which microbiota may exert their influence on niche cells and possibly on IESCs directly. Finally, we present an overview of the benefits and limitations of available tools to study niche-microbe interactions and provide our recommendations regarding their use and standardization. The study of host-microbe interactions in the gut is a rapidly growing field, and the IESC niche is at the forefront of host-microbe activity to control nutrient absorption, endocrine signaling, energy homeostasis, immune response, and systemic health.

scholarly journals Inheritance of seasonal cycles in Chrysoperla (Insecta: Neuroptera)

1987 ◽  
Vol 49 (3) ◽  
pp. 215-223 ◽  
Author(s):  
Catherine A. Tauber ◽  
Maurice J. Tauber
Keyword(s):  
Species Complex ◽  
Chrysoperla Carnea ◽  
Seasonal Cycles ◽  
Reproductive Diapause ◽  
Short Day ◽  
Long Day ◽  
Genetic Systems ◽  
Geographical Populations ◽  
Photoperiodic Responses ◽  
Polygenic System

SummaryTwo separate, but interacting, genetic systems underlie the variation in seasonal cycles among members of the Chrysoperla carnea species-complex. The two systems are expressed as all-or-none reproductive responses to photoperiod and prey (i.e. short-day/long-day requirement for reproduction versus long-day reproduction and prey requirement for reproduction versus reproduction without prey). In each case the alternative to reproduction is reproductive diapause. The photoperiodic responses are determined by alleles at two unlinked autosomal loci. The expression of dominance by the alleles at these loci varies among geographical populations. The genes that determine the photoperiodic responses also act as suppressors of the genes that govern responsiveness to prey. An autosomal, polygenic system, with a threshold for the expression of diapause, determines responsiveness to prey. The two genetic systems are important to seasonal diversification and speciation within the C. carnea species-complex.

Quantitative control of flowering time in wheat cultivars by vernalization and photoperiod sensitivities

1973 ◽  
Vol 24 (5) ◽  
pp. 657 ◽  
Author(s):  
JR Syme
Keyword(s):  
Environmental Changes ◽  
Day Treatment ◽  
Linear Regression Analysis ◽  
Multiple Linear Regression Analysis ◽  
Regression Equations ◽  
Wheat Cultivars ◽  
Sowing Time ◽  
P Values ◽  
Long Day ◽  
Cultivar Variation

Vernalization sensitivity (V) and photoperiod sensitivity (P) were measured in a range of wheat cultivars by the hastening of development brought about by seed vernalization and long-day treatment, respectively. Using multiple linear regression analysis V and P accounted for 77-94 % of cultivar variation in the time from sowing to ear emergence, or to anthesis, over 19 sowings at three sites. From the regression equations, the optimum combination of P and V for adaptation to variable sowing time was estimated. In two cases this was predicted to be a wheat with high V and low P values. Seasonal changes in the coefficients of the multiple regression equations were related to environmental changes in temperatures and photoperiod.

Coffee polyphenols suppress diet-induced body fat accumulation by downregulating SREBP-1c and related molecules in C57BL/6J mice

2011 ◽  
Vol 300 (1) ◽  
pp. E122-E133 ◽  
Author(s):  
Takatoshi Murase ◽  
Koichi Misawa ◽  
Yoshihiko Minegishi ◽  
Masafumi Aoki ◽  
Hideo Ominami ◽  
...  
Keyword(s):  
Body Fat ◽  
High Fat Diet ◽  
Active Form ◽  
Pyruvate Dehydrogenase Kinase ◽  
Liver Fat ◽  
Mrna Levels ◽  
Acetyl Coa Carboxylase ◽  
High Fat ◽  
Acetyl Coa ◽  
Fat Accumulation

The prevalence of obesity is increasing globally, and obesity is a major risk factor for type 2 diabetes and cardiovascular disease. We investigated the effects of coffee polyphenols (CPP), which are abundant in coffee and consumed worldwide, on diet-induced body fat accumulation. C57BL/6J mice were fed either a control diet, a high-fat diet, or a high-fat diet supplemented with 0.5 to 1.0% CPP for 2–15 wk. Supplementation with CPP significantly reduced body weight gain, abdominal and liver fat accumulation, and infiltration of macrophages into adipose tissues. Energy expenditure evaluated by indirect calorimetry was significantly increased in CPP-fed mice. The mRNA levels of sterol regulatory element-binding protein (SREBP)-1c, acetyl-CoA carboxylase-1 and -2, stearoyl-CoA desaturase-1, and pyruvate dehydrogenase kinase-4 in the liver were significantly lower in CPP-fed mice than in high-fat control mice. Similarly, CPP suppressed the expression of these molecules in Hepa 1–6 cells, concomitant with an increase in microRNA-122. Structure-activity relationship studies of nine quinic acid derivatives isolated from CPP in Hepa 1–6 cells suggested that mono- or di-caffeoyl quinic acids (CQA) are active substances in the beneficial effects of CPP. Furthermore, CPP and 5-CQA decreased the nuclear active form of SREBP-1, acetyl-CoA carboxylase activity, and cellular malonyl-CoA levels. These findings indicate that CPP enhances energy metabolism and reduces lipogenesis by downregulating SREBP-1c and related molecules, which leads to the suppression of body fat accumulation.

DIAPAUSE IN CHRYSOPA CARNEA (NEUROPTERA: CHRYSOPIDAE): I. EFFECT OF PHOTOPERIOD ON REPRODUCTIVELY ACTIVE ADULTS

1969 ◽  
Vol 101 (4) ◽  
pp. 364-370 ◽  
Author(s):  
Maurice J. Tauber ◽  
Catherine A. Tauber
Keyword(s):  
Fat Body ◽  
Colour Change ◽  
Rapid Decline ◽  
Reproductive Diapause ◽  
Short Day ◽  
Long Day ◽  
Chrysopa Carnea ◽  
Males And Females ◽  
Active Adults ◽  
Lighting Regimen

AbstractUpon transfer to a photoperiod of LD 12:12 all young, reproductively active Chrysopa carnea Stephens, reared and maintained under LD 16:8, showed a rapid decline in fecundity. One group entered diapause, as shown by the cessation of oviposition within 22 to 34 days, fat body accumulation, and an associated colour change. The females in this group resumed oviposition within 3 to 7 days after being returned to LD 16:8. Females in the other group under short-day conditions continued to oviposit, but at a lower rate than those kept under constant LD 16:8. Our data indicate that the imago is sensitive to both long-day and short-day photoperiods and that some males and females enter a facultative reproductive diapause which is induced and terminated in this stage solely by manipulating the adult lighting regimen.

Hormones, Circadian Rhythms, and Mental Health

2019 ◽  
pp. 365-379
Author(s):  
Yasmine-Marie Cisse ◽  
Jeremy C. Borniger ◽  
Randy J. Nelson
Keyword(s):  
Mental Health ◽  
Circadian Rhythms ◽  
Environmental Changes ◽  
Night Shift ◽  
Endocrine System ◽  
The Body ◽  
Affective Symptoms ◽  
Nighttime Light ◽  
Mood And Cognition ◽  
Endocrine Signaling

Circadian rhythms permit adaptations to predictable temporal environmental changes. Daily 24-hour rhythms are controlled by molecular clockworks within the brain that are set by the daily light–dark cycle. Downstream endocrine signaling conveys temporal information throughout the body. Mood disorders often present with disruptions in circadian clock-controlled responses, such as sleep and cortisol secretion, whereas circadian rhythm disruptions via jet lag, night-shift work, or light at night increase disordered affective symptoms. Evidence suggests strong associations between circadian rhythms and mental health, but only recently have studies begun to discover the direct interactions between the circadian system and mood regulation. This chapter provides an overview of circadian rhythms and the circadian regulation of the endocrine system. It discusses how the circadian and endocrine systems interact to affect depressive, anxious, and addictive responses. Finally, it discusses the potential detrimental effects the widespread use of nighttime light has for mood and cognition.

scholarly journals The Contribution of “Alternative Approaches” to Understanding Steroid Hormone Action

2005 ◽  
Vol 19 (6) ◽  
pp. 1439-1442 ◽  
Author(s):  
Elwood V. Jensen
Keyword(s):  
Hormone Receptor ◽  
Steroid Hormone ◽  
Chemical Change ◽  
Active Form ◽  
Steroid Hormone Receptor ◽  
Breast Cancers ◽  
Step Process ◽  
Cellular Processes ◽  
Standard Clinical Practice ◽  
Soluble Immune Complexes

Abstract In the 47 yr since the first evidence for a steroid hormone receptor was presented at an international congress to an audience of five persons, the concept of “alternative approach” has played an important role in providing new understanding. By asking not what does an estrogenic hormone do to cellular processes in responsive tissues but what do these cells do to the hormone, it was shown that rat uterus contains a characteristic protein with which the hormone associates to promote growth. In the following decade, it was established that this substance is a true receptor, involved in hormonal action. Furthermore, estradiol was found not to undergo a chemical change as it exerts its effect. Finally, estrogenic action was established as a two-step process in which association with the hormone converts the receptor from an inactive to an active form that can bind tightly in the nucleus to modify transcription. These findings, obtained by studying the fate of the hormone itself, disproved the then accepted concept that estrogens interact with enzyme systems, and opened a new field of research. Soon various laboratories identified intracellular receptors for all classes of steroid hormones, the action of which involves a similar two-step process. Several laboratories then attempted, without success, to obtain antibodies to these receptors by conventional techniques. The unconventional approach of gradient ultracentrifugation, using radioactive estradiol as a marker for the receptor, gave a means of recognizing the soluble immune complexes formed with estrogen receptor and provided the first antibodies to any steroid hormone receptor, permitting its cloning. Finally, the knowledge that estrogens act through a receptor suggested that measuring the receptor content of an excised tumor specimen could identify, in advance, two thirds of the human breast cancers that are not estrogen dependent. These patients will not benefit from endocrine ablation or antiestrogen treatment and should be placed directly on chemotherapy. This is now standard clinical practice.

scholarly journals G3BPs in Plant Stress

2021 ◽  
Vol 12 ◽  
Author(s):  
Aala A. Abulfaraj ◽  
Heribert Hirt ◽  
Naganand Rayapuram
Keyword(s):  
Plant Stress ◽  
Active Form ◽  
Environmental Stresses ◽  
Processing Bodies ◽  
Post Translational Modifications ◽  
P Bodies ◽  
Adverse Conditions ◽  
Mrna Metabolism ◽  
Evolutionarily Conserved

The sessile nature of plants enforces highly adaptable strategies to adapt to different environmental stresses. Plants respond to these stresses by a massive reprogramming of mRNA metabolism. Balancing of mRNA fates, including translation, sequestration, and decay is essential for plants to not only coordinate growth and development but also to combat biotic and abiotic environmental stresses. RNA stress granules (SGs) and processing bodies (P bodies) synchronize mRNA metabolism for optimum functioning of an organism. SGs are evolutionarily conserved cytoplasmic localized RNA-protein storage sites that are formed in response to adverse conditions, harboring mostly but not always translationally inactive mRNAs. SGs disassemble and release mRNAs into a translationally active form upon stress relief. RasGAP SH3 domain binding proteins (G3BPs or Rasputins) are “scaffolds” for the assembly and stability of SGs, which coordinate receptor mediated signal transduction with RNA metabolism. The role of G3BPs in the formation of SGs is well established in mammals, but G3BPs in plants are poorly characterized. In this review, we discuss recent findings of the dynamics and functions of plant G3BPs in response to environmental stresses and speculate on possible mechanisms such as transcription and post-translational modifications that might regulate the function of this important family of proteins.

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