Mystery at the heart of life

_{News
December 21, 2014

Cell biology, Intelligent Design, News

1}_{Categories
Cell biology
Intelligent Design
News}

Share: Facebook; Twitter/X; LinkedIn; Flipboard; Print; Email

By Biologic Institute’s Ann Gauger, at Christianity Today’s Behemoth, the secret life of cells:

Our bodies are made up of some 100 trillion cells. We tend to think of cells as static, because that’s how they were presented to us in textbooks. In fact, the cell is like the most antic, madcap, crowded (yet fantastically efficient) city you can picture. And at its heart lies a mystery—or I should say, several mysteries—involving three special kinds of molecules: DNA, RNA, and proteins.

These molecules are assembled into long chains called polymers, and are uniquely suited for the roles they play. More importantly, life absolutely depends upon them. We have to have DNA, RNA, and protein all present and active at the same time for a living organism to live.

How they work together so optimally and efficiently is not merely amazing, but also a great enigma, a mystery that lies at the heart of life itself. More. Paywall soon after. May be worth it.

Follow UD News at Twitter!

Comments

Further mechanistic molecular studies are needed to understand the role of AHR regulating self-renewal responses of tissue-resident stem cells niches or whether AHR participates in self-renewal by promoting release of factors by the stem cells themselves. Further studies need to consider whether stem cells may be regulated by AHR ligands via alternative binding pockets which may in turn lead to binding to alternative AHR responsive elements and regulation of different gene promoters. [...] further studies using molecular tools may provide information about the specific players involved.
The Aryl Hydrocarbon Receptor Relays Metabolic Signals to Promote Cellular Regeneration Fanny L. Casado Stem Cells Int. 2016; 2016: 4389802. doi: 10.1155/2016/4389802

Complex complexity.Dionisio_{October 11, 2016
October
10
Oct
11
11
2016
07:33 PM
7
07
33
PM
PDT}

[...] formation of apical projections is under the control of mechanisms involved in establishment and maintenance of epithelial cell polarity. [...] further investigations are required to identify additional components or polarity regulator/s that act in conjunction with the two Lgls in formation of apical microridges.
aPKC regulates apical localization of Lgl to restrict elongation of microridges in developing zebrafish epidermis Renuka Raman,1 Indraneel Damle,1 Rahul Rote,1,* Shamik Banerjee,1,2 Chaitanya Dingare,1,† and Mahendra Sonawane Nat Commun. 7: 11643. doi: 10.1038/ncomms11643

Dionisio_{October 10, 2016
October
10
Oct
10
10
2016
07:40 PM
7
07
40
PM
PDT}

Biological phenomena, such as development, are complex dynamic processes. They cannot be reduced to the characteristics of their components and need to be described by interactions within multiple hierarchical levels comprising a system. [...] temporally co-ordinated signals from numerous effector pathways define the divergent cell fates. [...] it is not clear whether de- and redifferentiation operate as a bidirectional process or which elements predominate during these transitions [...] [...] the underlying gene regulatory mechanisms are still not understood well enough to inform the design process. Future experimental systems must be designed in concert with mathematical models to integrate the complex biomechanical and biochemical signalling4
A systems biology approach to defining regulatory mechanisms for cartilage and tendon cell phenotypes. Mueller AJ1, Tew SR1,2, Vasieva O3, Clegg PD1,2, Canty-Laird EG Sci Rep. 6:33956. doi: 10.1038/srep33956.

Dionisio_{October 10, 2016
October
10
Oct
10
10
2016
07:13 PM
7
07
13
PM
PDT}

[...] excellent progress has been made in elucidating both the signaling pathways and the transcriptional regulatory networks that control [...] Mechanical signals [...] have also been shown to be important regulators of both chondrocyte proliferation and bone morphology. However, the details regarding how these various signals modulate either the expression and/or activity of the relevant transcription factors is only beginning to be explored. Such a detailed molecular understanding will be necessary to fully comprehend how either the initiation of chondrogenesis or growth plate expansion is regulated with such precision during vertebrate development.
A pathway to bone: signaling molecules and transcription factors involved in chondrocyte development and maturation Elena Kozhemyakina,1 Andrew B. Lassar,1,* and Elazar Zelzer2 Development. 142(5): 817–831. doi: 10.1242/dev.105536

There yet? Nope, but we're just missing the details. Not a big deal, is it? :) Complex complexity. :)Dionisio_{October 10, 2016
October
10
Oct
10
10
2016
05:16 AM
5
05
16
AM
PDT}

The parameters that dictate whether a hypertrophic chondrocyte will either undergo apoptosis or initiate the osteogenic differentation program and survive in the bone matrix are not yet understood. It is not clear what controls these strikingly different responses to Fgf18 signaling at differing stages of growth plate development.
A pathway to bone: signaling molecules and transcription factors involved in chondrocyte development and maturation Elena Kozhemyakina,1 Andrew B. Lassar,1,* and Elazar Zelzer2 Development. 142(5): 817–831. doi: 10.1242/dev.105536

There yet? Nope, but we're just missing the details. Not a big deal, is it? :) Complex complexity. :)Dionisio_{October 10, 2016
October
10
Oct
10
10
2016
05:14 AM
5
05
14
AM
PDT}

Endochondral ossification consists of successive steps of chondrocyte differentiation, including mesenchymal condensation, differentiation of chondrocytes, and hypertrophy followed by mineralization and ossification. [...] Cdc42 is involved not in osteogenesis but in chondrogenesis in which the BMP2/Cdc42/Pak/p38/Smad signaling module promotes mesenchymal condensation and the TGF-?/Cdc42/Pak/Akt/Sox9 signaling module facilitates chondrogenic differentiation.
Signaling Cascades Governing Cdc42-Mediated Chondrogenic Differentiation and Mensenchymal Condensation. Wang JR1, Wang CJ2, Xu CY1, Wu XK1, Hong D2, Shi W1, Gong Y1, Chen HX3, Long F4, Wu XM5. Genetics. 202(3):1055-69. doi: 10.1534/genetics.115.180109.

Complex complexity. :)Dionisio_{October 10, 2016
October
10
Oct
10
10
2016
04:25 AM
4
04
25
AM
PDT}

butifnot @2112: Thank you for the interesting comments.Dionisio_{October 10, 2016
October
10
Oct
10
10
2016
04:16 AM
4
04
16
AM
PDT}

Future directions will be aimed at acquiring a deeper mechanistic understanding of the roles of FGF signaling in development and in adult tissues with a goal of understanding how these pathways become reactivated during injury response and cancer. [...] it remains unclear whether polymorphisms result in gain- or loss-of-function.
The Fibroblast Growth Factor signaling pathway David M Ornitz and Nobuyuki Itoh Wiley Interdiscip Rev Dev Biol. 4(3): 215–266. doi: 10.1002/wdev.176

Dionisio_{October 9, 2016
October
10
Oct
9
09
2016
12:28 PM
12
12
28
PM
PDT}

Fascinating Dionisio. I am particularly interested in electric fields as a mechanism of coordination/control/signaling/ etc etc. Maybe a global field as well as superposed fields. Also, I remember reading of some research which began as an investigation of why two isomers were so vastly different in effect one being highly toxic and the other benign. The investigator noticed that the toxic one was opaque to uv wavelengths and went on to develop the idea that intra/inter cellular communication occurred with uv light emissions of single to several photon intensity. With experiments of biological communication being stopped by uv-opaque separation. The coordination, and control, and meta-information processing, that has been unknown, unaddressed, undiscovered, makes most of what has been ascertained trivial by comparison. Seems like much of DNA is ingredients and the recipe is going to blow our minds.butifnot_{October 9, 2016
October
10
Oct
9
09
2016
02:01 AM
2
02
01
AM
PDT}

The fact that cells are being constantly displaced from the distal mesenchyme by an intrinsically timed programme of proliferation thus provides a robust mechanism by which a precise gradient of positional values can become established [...] [...] an intrinsic cell cycle clock, sustained by AER signalling, is part of the timing mechanism that specifies the positional values of the zeugopod and autopod. [...] it is unclear how the specification of positional values relates to the final limb anatomy [...] [...] it is tempting to speculate that a link between this process of self-organization and cell adhesion exists. The possibility that permissive AER signals increase over time, which has never been demonstrated, cannot be excluded and requires further investigation. A fundamental issue is whether extrinsic signals or an intrinsic timer re-specifies missing positional values during limb regeneration. [...] an emerging theme is that both signal and time-based mechanisms operate together during embryogenesis. Whether timing in other patterning systems is an intrinsic property remains largely undetermined.
An intrinsic timer specifies distal structures of the vertebrate limb Patricia Saiz-Lopez,1,* Kavitha Chinnaiya,2,* Victor M. Campa,1 Irene Delgado,1,† Maria A. Ros,a,1,3 and Matthew Towers Nat Commun. 6: 8108. doi: 10.1038/ncomms9108

Dionisio_{October 9, 2016
October
10
Oct
9
09
2016
12:22 AM
12
12
22
AM
PDT}

An enigmatic problem in developmental biology is how the positional values along the proximo-distal axis (that is, humerus to digits) of the vertebrate limb are specified. Although this has been a topic of intense investigation, a consensus model has not been reached. [...] the positional values of the zeugopod and autopod are progressively specified in an intrinsically timed manner.
An intrinsic timer specifies distal structures of the vertebrate limb Patricia Saiz-Lopez,1,* Kavitha Chinnaiya,2,* Victor M. Campa,1 Irene Delgado,1,† Maria A. Ros,a,1,3 and Matthew Towers Nat Commun. 6: 8108. doi: 10.1038/ncomms9108

Complex complexity.Dionisio_{October 8, 2016
October
10
Oct
8
08
2016
11:25 PM
11
11
25
PM
PDT}

How the positional values along the proximo-distal axis (stylopod-zeugopod-autopod) of the limb are specified is intensely debated. Early work suggested that cells intrinsically change their proximo-distal positional values by measuring time. Recently, however, it is suggested that instructive extrinsic signals from the trunk and apical ectodermal ridge specify the stylopod and zeugopod/autopod, respectively. [...] the zeugopod and autopod are specified by an intrinsic timing mechanism. [...] distal mesenchyme cells intrinsically time Hoxa13 expression, cell cycle parameters and the duration of the overlying apical ectodermal ridge. [...] cell affinities intrinsically change in the distal mesenchyme [leading to] a gradient of positional values along the proximo-distal axis. [they propose] a complete model in which a switch from extrinsic signalling to intrinsic timing patterns the vertebrate limb.
An intrinsic timer specifies distal structures of the vertebrate limb Patricia Saiz-Lopez,1,* Kavitha Chinnaiya,2,* Victor M. Campa,1 Irene Delgado,1,† Maria A. Ros,a,1,3 and Matthew Towers Nat Commun. 6: 8108. doi: 10.1038/ncomms9108

Dionisio_{October 8, 2016
October
10
Oct
8
08
2016
11:10 PM
11
11
10
PM
PDT}

A future challenge will be to see if similar retinoic acid gradients and noise control occur in other tissues, and if the noise has any positive role to play in development. Morphogens are long-range signals thought to induce different cell behaviors in a concentration-dependent manner, but how such graded signals can be established in the face of noise and how they specify sharp boundaries of target gene expression remain unclear.
Noise modulation in retinoic acid signaling sharpens segmental boundaries of gene expression in the embryonic zebrafish hindbrain. Sosnik J1,2,3, Zheng L2,4, Rackauckas CV2,4, Digman M1,2,5, Gratton E1,2,5, Nie Q1,2,4, Schilling TF1,2. Elife. 5:e14034. doi: 10.7554/eLife.14034.

Dionisio_{October 8, 2016
October
10
Oct
8
08
2016
05:52 PM
5
05
52
PM
PDT}

Morphogen gradients induce sharply defined domains of gene expression in a concentration-dependent manner, yet how cells interpret these signals in the face of spatial and temporal noise remains unclear. [...] RA forms a noisy gradient during critical stages of hindbrain patterning and that cells use distinct intracellular binding proteins to attenuate noise in RA levels. Increasing noise disrupts sharpening of rhombomere boundaries and proper patterning of the hindbrain. These findings reveal novel cellular mechanisms of noise regulation, which are likely to play important roles in other aspects of physiology and disease.
Noise modulation in retinoic acid signaling sharpens segmental boundaries of gene expression in the embryonic zebrafish hindbrain. Sosnik J1,2,3, Zheng L2,4, Rackauckas CV2,4, Digman M1,2,5, Gratton E1,2,5, Nie Q1,2,4, Schilling TF1,2. Elife. 5:e14034. doi: 10.7554/eLife.14034.

Dionisio_{October 8, 2016
October
10
Oct
8
08
2016
05:35 AM
5
05
35
AM
PDT}

#2104 error correction: Where it reads "shy?" it should read "why?" instead. Sorry for this mistake. I wasn't careful enough. Should review the text before posting it. My fault.Dionisio_{October 8, 2016
October
10
Oct
8
08
2016
05:19 AM
5
05
19
AM
PDT}

Morphogens were originally defined as secreted signaling molecules that diffuse from local sources to form concentration gradients, which specify multiple cell fates. More recently morphogen gradients have been shown to incorporate a range of mechanisms including short-range signal activation, transcriptional/translational feedback, and temporal windows of target gene induction. Many critical cell-cell signals implicated in both embryonic development and disease, such as Wnt, fibroblast growth factor (Fgf), hedgehog (Hh), transforming growth factor beta (TGFb), and retinoic acid (RA), are thought to act as morphogens, but key information on signal propagation and ligand distribution has been lacking for most. The zebrafish provides unique advantages for genetics and imaging to address gradients during early embryonic stages when morphogens help establish major body axes. This has been particularly informative for RA, where RA response elements (RAREs) driving fluorescent reporters as well as Fluorescence Resonance Energy Transfer (FRET) reporters of receptor binding have provided evidence for gradients, as well as regulatory mechanisms that attenuate noise and enhance gradient robustness in vivo.
Visualizing retinoic acid morphogen gradients. Schilling TF, Sosnik J, Nie Q Methods Cell Biol. 133:139-63. doi: 10.1016/bs.mcb.2016.03.003.

Just ask professor L.M. of the U of T in Canada. :) But make sure to ask only honest questions, whatever that means. :) Complex complexity. :)Dionisio_{October 8, 2016
October
10
Oct
8
08
2016
05:11 AM
5
05
11
AM
PDT}

[...] there must be other molecules and mechanisms in the embryo that refine and shape the Nodal morphogen gradient. [...] one possible mechanism to shape the gradient is transient binding of Nodal proteins to immobilized diffusion regulators [...] Another potential mechanism for gradient formation is rapid clearance of molecules during diffusion [...] [...] cells selectively destroy Nodal ligands by recognizing the lysosome-targeting signal, since the ligands have to be internalized. [...] the Nodal gradient is dependent upon diffusion, binding, and degradation of the morphogen. [...] some aspects of the system have not been taken into account in our simulations. It will be interesting to determine how Oep/Cripto co-receptors and Lefty shape the active signaling gradient. It is not known if the ECM or HSPGs play a role in modulating the Nodal morphogen gradient [...] [...] in addition to hindered diffusion via binding to the receptors and inhibitors, the differential stability of Nodal ligands play key roles in shaping the Nodal gradient and activity range. [...] diffusion, extracellular interactions i.e., Nodal-receptor binding, Nodal-Lefty inhibitor binding, and selective ligand destruction collectively shape and refine the Nodal morphogen gradient.
Extracellular interactions and ligand degradation shape the nodal morphogen gradient Yin Wang, Xi Wang, Thorsten Wohland and Karuna Sampath eLife. 2016; 5: e13879. doi: 10.7554/eLife.13879

ECM: extracellular matrix HSPGs: heparan sulphate proteoglycans Do the conclusions of this research paper mean that all the previous hype about Turing and diffusion related to the morphogen gradient formation was premature? Are we ever going to see more humility in scientific research? Why did it take them so long to realize that diffusion alone could not explain the whole enchilada? A child could have figured that out much faster, by simply asking the humble "how?" and "shy?" questions right from the start. Why can't scientists approach research with that sense of wonder, with open mind, thinking out of pre-established boxes, beyond biased preconceived standards? Just ask professor L.M. of the U of T in Canada. :) But make sure to ask only honest questions, whatever that means. :) Complex complexity. :)Dionisio_{October 8, 2016
October
10
Oct
8
08
2016
04:56 AM
4
04
56
AM
PDT}

In contrast to the differential diffusion model, a recent study suggested that a temporal signal activation window created by microRNA-430 (miRNA-430) delays translation of the Nodal antagonist Lefty to determine the dimensions of Nodal signaling in the gastrula [...] [...] it is unclear how the proposed temporal activation window might be converted into a spatial Nodal gradient Some studies have suggested that in addition to diffusion, the gradient of a morphogen is related to the rate of ligand clearance or stability [...] How the lysosome-targeting region regulates Nodal clearance and how it influences the Nodal morphogen gradient was not known. [...] diffusivity alone is insufficient to generate the Nodal morphogen gradient. [...] in order to generate and maintain a robust Nodal morphogen gradient, ligand clearance by degradation is balanced against the binding and release of Nodal ligands with the receptor and inhibitors.
Extracellular interactions and ligand degradation shape the nodal morphogen gradient Yin Wang, Xi Wang, Thorsten Wohland and Karuna Sampath eLife. 2016; 5: e13879. doi: 10.7554/eLife.13879

Does this mean that all the hype about Turing and diffusion related to the morphogen gradient formation was premature? Are we ever going to see more humility in scientific research papers? Just ask professor L.M. of the U of T in Canada. :) But make sure to ask only honest questions, whatever that means. :) Complex complexity. :)Dionisio_{October 8, 2016
October
10
Oct
8
08
2016
04:15 AM
4
04
15
AM
PDT}

[...] until now it was not fully clear how the well-known morphogen called Nodal moves in live zebrafish as they develop. [...] in addition to Nodal diffusing and binding to receiving cells, one of the most important factors determining how far and quickly Nodal moves is its inactivation and destruction. [...] diffusivity, extra-cellular interactions, and selective ligand destruction collectively shape the Nodal morphogen gradient. [...] future experiments will aim to examine these molecules and their interactions when they are produced at their normal locations in the animal over time.
Extracellular interactions and ligand degradation shape the nodal morphogen gradient Yin Wang, Xi Wang, Thorsten Wohland and Karuna Sampath eLife. 2016; 5: e13879. doi: 10.7554/eLife.13879

Just ask professor L.M. of the U of T in Canada. :)Dionisio_{October 8, 2016
October
10
Oct
8
08
2016
03:31 AM
3
03
31
AM
PDT}

How morphogen gradients are formed is not fully understood. Studies in many organisms have suggested three major mechanisms to establish morphogen gradients: 1) diffusion, 2) transcytosis and 3) via cytonemes Nodal proteins, which belong to the TGF-? family of signaling proteins, play critical roles in vertebrate development [...] [...] the Nodal morphogen gradient has been proposed to be established by simple diffusion [...] How Nodal diffusion is hindered, and to what extent it shapes the Nodal gradient is unclear.
Extracellular interactions and ligand degradation shape the nodal morphogen gradient Yin Wang, Xi Wang, Thorsten Wohland and Karuna Sampath eLife. 2016; 5: e13879. doi: 10.7554/eLife.13879

Just ask professor L.M. of the U of T in Canada. :)Dionisio_{October 8, 2016
October
10
Oct
8
08
2016
03:26 AM
3
03
26
AM
PDT}

The correct distribution and activity of secreted signaling proteins called morphogens is required for many developmental processes. Nodal morphogens play critical roles in embryonic axis formation in many organisms. Models proposed to generate the Nodal gradient include diffusivity, ligand processing, and a temporal activation window. But how the Nodal morphogen gradient forms in vivo remains unclear.
Extracellular interactions and ligand degradation shape the nodal morphogen gradient Yin Wang, Xi Wang, Thorsten Wohland and Karuna Sampath eLife. 2016; 5: e13879. doi: 10.7554/eLife.13879

Just ask professor L.M. of the U of T in Canada. :)Dionisio_{October 8, 2016
October
10
Oct
8
08
2016
03:18 AM
3
03
18
AM
PDT}

Pressing questions remain unanswered, and there is a glaring need for human studies addressing these. Recent studies have also begun exploring how clock gene SNPs may influence responses to dietary interventions [...], and ultimately knowledge of circadian system gene variants may also help inform personalized nutrition. There are also several non-essential dietary compounds consistently shown to influence the circadian system. Further research is needed to see if such compounds might be useful in humans, however. If they are, what are the best times to consume them to maximise their impact, and what are the dose-response and phase-response curves of these compounds? Continuing collaboration between chronobiologists and nutritionists will further clarify interactions between nutrition and the circadian system, and ultimately has the potential to reduce the prevalence and burden of chronic diseases.
Nutrition and the Circadian System Gregory D M Potter,1 Janet E Cade,2 Peter J Grant,3 and Laura J Hardie Br J Nutr. 116(3): 434–442. doi: 10.1017/S0007114516002117

SNP: single-nucleotide polymorphisms TRF: time-of-day-restricted feedingDionisio_{October 8, 2016
October
10
Oct
8
08
2016
02:50 AM
2
02
50
AM
PDT}

The human circadian system anticipates and adapts to daily environmental changes to optimise behaviour according to time of day and temporally partition incompatible physiological processes. At the helm of this system is a master clock in the suprachiasmatic nuclei (SCN) of the anterior hypothalamus. An appreciation of the circadian system has many implications for nutritional science and may ultimately help reduce the burden of chronic diseases.
Nutrition and the Circadian System Gregory D M Potter,1 Janet E Cade,2 Peter J Grant,3 and Laura J Hardie Br J Nutr. 116(3): 434–442. doi: 10.1017/S0007114516002117

Dionisio_{October 8, 2016
October
10
Oct
8
08
2016
02:22 AM
2
02
22
AM
PDT}

Feeding behavior, metabolism and circadian clocks are interlinked. Calorie restriction (CR) is a feeding paradigm known to extend longevity CR recruits biological clocks as a natural mechanism of metabolic optimization under conditions of limited energy resources. Future study focused on the effects of CR in circadian clock mutants will help to clarify connections between clock and CR.
Calorie restriction regulates circadian clock gene expression through BMAL1 dependent and independent mechanisms Sonal A. Patel,1 Nikkhil Velingkaar,1 Kuldeep Makwana,1 Amol Chaudhari,1 and Roman Kondratova,1 Sci Rep. 6: 25970. doi: 10.1038/srep25970

Dionisio_{October 7, 2016
October
10
Oct
7
07
2016
06:13 PM
6
06
13
PM
PDT}

A series of fascinating discoveries in the field of circadian rhythms have revealed the direct implication of the clock in the maintenance of cellular homeostasis. [...] the circadian transcriptional landscape seems highly complex as it implicates dynamic changes in nuclear organization [...] Understanding how the nuclear landscape integrates metabolic cues and shapes the transcriptional output will be of great importance. Unravelling the mechanisms leading to metabolic syndromes is critical because it may expose key molecular players in the circadian control of glucose or lipid homeostasis.
Chromatin landscape and circadian dynamics: Spatial and temporal organization of clock transcription Lorena Aguilar-Arnal and Paolo Sassone-Corsi Proc Natl Acad Sci U S A. 112(22): 6863–6870. doi: 10.1073/pnas.1411264111 PMCID: PMC4460512 Cell Biology

Dionisio_{October 7, 2016
October
10
Oct
7
07
2016
05:38 PM
5
05
38
PM
PDT}

An additional regulatory layer is achieved through noncoding RNAs. Further investigations are necessary to decipher the functional characteristics of these oscillatory noncoding RNAs and how they impact circadian transcription. The extent of the influence that chromatin topological organization has on the circadian transcriptome needs to be determined. Further research is necessary to decipher the impact of one carbon metabolism in the circadian transcriptome. The coordination and integration of metabolic pathways within the circadian epigenome appear intricate. To which extent genome topology senses circadian metabolism remains to be explored.
Chromatin landscape and circadian dynamics: Spatial and temporal organization of clock transcription Lorena Aguilar-Arnal and Paolo Sassone-Corsi Proc Natl Acad Sci U S A. 112(22): 6863–6870. doi: 10.1073/pnas.1411264111 PMCID: PMC4460512 Cell Biology

Dionisio_{October 7, 2016
October
10
Oct
7
07
2016
05:31 PM
5
05
31
PM
PDT}

The circadian clock is an endogenous timekeeper present in almost all life forms. [...] the clock system is not driven by external “zeitgebers” (a German word that means time-giver), but it is rather synchronized or entrained by zeitgebers every day to adjust to the 24-h period. [...] the circadian clock generates an internal biological rhythm that synchronizes and adapts to the changing environment. In mammals, the master clock resides in the suprachiasmatic nucleus (SCN) of the hypothalamus, which receives external light information from the retina through the retinohypothalamic tract. The mechanisms involved in the communication between the SCN and the periphery remain poorly explored although they are thought to be complex and multilayered.
Chromatin landscape and circadian dynamics: Spatial and temporal organization of clock transcription Lorena Aguilar-Arnal and Paolo Sassone-Corsi Proc Natl Acad Sci U S A. 112(22): 6863–6870. doi: 10.1073/pnas.1411264111 PMCID: PMC4460512 Cell Biology

Dionisio_{October 7, 2016
October
10
Oct
7
07
2016
05:27 PM
5
05
27
PM
PDT}

Circadian rhythms drive the temporal organization of a wide variety of physiological and behavioral functions in ?24-h cycles. This control is achieved through a complex program of gene expression. Deciphering the molecular mechanisms that connect the circadian clock machinery with the nuclear landscape will reveal yet unexplored pathways that link cellular metabolism to epigenetic control.
Chromatin landscape and circadian dynamics: Spatial and temporal organization of clock transcription Lorena Aguilar-Arnal and Paolo Sassone-Corsi Proc Natl Acad Sci U S A. 112(22): 6863–6870. doi: 10.1073/pnas.1411264111 PMCID: PMC4460512 Cell Biology

Dionisio_{October 7, 2016
October
10
Oct
7
07
2016
03:42 PM
3
03
42
PM
PDT}

The mammalian circadian system is organized as a hierarchy of oscillators, with the master pacemaker located in the suprachiasmatic nucleus (SCN) of the hypothalamus. Circadian oscillators are present in almost all tissues of an organism, and the SCN orchestrates their coordinated function. The control that the circadian clock exerts on cellular metabolism is complex and multilayered, yet numerous underlying molecular mechanisms are being unraveled. [...] the circadian clock, a well-coordinated transcription-translation feedback system that orchestrates and integrates gene expression, protein stability and metabolite production to keep correct time. The extent of metabolic influence on clock function needs further investigation. The decoding of the language that links nutrients and metabolites to the circadian clock will be important to decipher how mis-regulation of circadian rhythms leads to chronic diseases such as obesity and diabetes.
Chromatin Dynamics of Circadian Transcription Lorena Aguilar-Arnal and Paolo Sassone-Corsi Curr Mol Biol Rep. 1(1): 1–9. doi: 10.1007/s40610-015-0001-7

Complex complexity on steroids. :)Dionisio_{October 7, 2016
October
10
Oct
7
07
2016
12:16 PM
12
12
16
PM
PDT}

The mammalian circadian system is organized as a hierarchy of oscillators, with the master pacemaker located in the suprachiasmatic nucleus (SCN) of the hypothalamus. Circadian oscillators are present in almost all tissues of an organism, and the SCN orchestrates their coordinated function.
Chromatin Dynamics of Circadian Transcription Lorena Aguilar-Arnal and Paolo Sassone-Corsi Curr Mol Biol Rep. 1(1): 1–9. doi: 10.1007/s40610-015-0001-7

Dionisio_{October 7, 2016
October
10
Oct
7
07
2016
11:54 AM
11
11
54
AM
PDT}

Prev 1 … 45 46 47 48 49 … 117 Next

You must be logged in to post a comment.

Leave a Reply