Optical evaluation of internal damage to human hair based on second near-infrared window polarization microscopy.

OBJECTIVE: Hair beauty treatments glorify human life. As a side effect, there is a risk of deteriorating the health of the hair. Optically polarized microscopy has been used for many decades to evaluate hair conditions owing to its ease of use and low operating costs. However, the low biopermeability of light hinders the observation of detailed structures inside hair. The aim of this study is to establish an evaluation technique of internal damages in a hair by utilizing a near-infrared (NIR) light with a wavelength of 1000-1600 nm, called "second NIR window". METHODS: We built a laser scanning transmission microscope system with an indium gallium arsenide detector, a 1064 nm laser source, and optical circular polarization to visualize the anisotropy characterization of keratin fibres in hair. Samples of Asian black hair before and after bleaching, after permanent-waving, after lithium bromide (LiBr) treatment, and after heating was observed. Some parameters reflecting intra-hair damage were quantitatively compared with the parameters in digitally recorded images with analytical developments. RESULTS: The light transmittance of black hair was dramatically improved by utilizing the second NIR window. Numerical analysis of circular polarization in hair quantified the internal damage in chemically or thermally treated hair and found two different types of damage. The present method enabled quantitative evaluation of the condition changes in the cortex; for example, a decrease in circular polarizability by LiBr treatment and restoration by replacing the LiBr solution with water. In addition, black speckles were observed after the heat treatment. Longer heating and wetting times increased the appearance probability and size of the speckles. According to quantitative analyses, the emergence of black spots was independent of polarizability changes, indicating that they were not pores. CONCLUSION: Circular polarization microscopy based on near-infrared optics in the second NIR window provides an effective evaluation method for quantifying intra-hair damage caused by cosmetic treatments. The present method provides noninvasive, easy, and inexpensive hair evaluation and has potential as a gold standard in hair care research/medical fields.

OBJECTIF: les soins capillaires glorifient la vie humaine. Comme effet secondaire, il existe un risque de détérioration de la santé du cheveu. La microscopie en lumière polarisée est utilisée depuis de nombreuses décennies pour évaluer la santé capillaire en raison de sa facilité d'utilisation et de son faible coût d'exploitation. Cependant, la faible bioperméabilité de la lumière empêche l'observation des structures détaillées à l'intérieur du cheveu. Pour résoudre ce problème, cette étude tente d'établir une technique d'évaluation des atteintes internes d'un cheveu en utilisant une lumière proche infrarouge (NIR) d'une longueur d'onde de 1000 à 1600 nm, appelée « deuxième fenêtre NIR ¼. MÉTHODES: nous avons construit un système de microscope de transmission à balayage laser équipé d'un capteur indium gallium arsenide, d'une source laser de 1064 nm et d'une polarisation circulaire optique pour visualiser la caractérisation de l'anisotropie des fibres de kératine dans les cheveux. Des échantillons de cheveux noirs asiatiques ont subi un traitement avant et après la décoloration, l'ondulation permanente, le bromure de lithium (LiBr) et la chaleur. Certains paramètres reflétant les dommages intra­cheveu ont été comparés quantitativement aux paramètres des images enregistrées numériquement avec des développements analytiques. RÉSULTATS: la transmission de la lumière des cheveux noirs a été considérablement améliorée en utilisant la deuxième fenêtre NIR. L'analyse numérique de la polarisation circulaire des cheveux a quantifié les dommages internes des cheveux traités chimiquement ou thermiquement et a mis en évidence deux types de dommages différents. La présente méthode a permis d'évaluer quantitativement les changements de condition dans le cortex; par exemple, une diminution de la polarisation circulaire par le traitement par LiBr et la restauration en remplaçant la solution LiBr par de l'eau. En outre, des taches noires ont été observées après le traitement thermique. Des temps de chauffage et de mouillage plus longs ont augmenté la fréquence d'apparition et la taille des taches. D'après des analyses quantitatives, l'émergence de points noirs était indépendante des changements de polarisation, indiquant qu'il ne s'agissait pas de pores. CONCLUSION: La microscopie par polarisation circulaire basée sur l'optique proche infrarouge dans la deuxième fenêtre NIR fournit une méthode d'évaluation efficace pour quantifier les dommages intra­cheveu causés par les traitements cosmétiques. La présente méthode fournit une évaluation des cheveux non invasive, facile et peu coûteuse et a un potentiel de référence dans la recherche sur les soins capillaires/les domaines médicaux.

Single-molecule tracking of Nanog and Oct4 in living mouse embryonic stem cells uncovers a feedback mechanism of pluripotency maintenance.

Nanog and Oct4 are core transcription factors that form part of a gene regulatory network to regulate hundreds of target genes for pluripotency maintenance in mouse embryonic stem cells (ESCs). To understand their function in the pluripotency maintenance, we visualised and quantified the dynamics of single molecules of Nanog and Oct4 in a mouse ESCs during pluripotency loss. Interestingly, Nanog interacted longer with its target loci upon reduced expression or at the onset of differentiation, suggesting a feedback mechanism to maintain the pluripotent state. The expression level and interaction time of Nanog and Oct4 correlate with their fluctuation and interaction frequency, respectively, which in turn depend on the ESC differentiation status. The DNA viscoelasticity near the Oct4 target locus remained flexible during differentiation, supporting its role either in chromatin opening or a preferred binding to uncondensed chromatin regions. Based on these results, we propose a new negative feedback mechanism for pluripotency maintenance via the DNA condensation state-dependent interplay of Nanog and Oct4.

Osteoblast/osteocyte-derived interleukin-11 regulates osteogenesis and systemic adipogenesis.

Exercise results in mechanical loading of the bone and stimulates energy expenditure in the adipose tissue. It is therefore likely that the bone secretes factors to communicate with adipose tissue in response to mechanical loading. Interleukin (IL)-11 is known to be expressed in the bone, it is upregulated by mechanical loading, enhances osteogenesis and suppresses adipogenesis. Here, we show that systemic IL-11 deletion (IL-11-/-) results in reduced bone mass, suppressed bone formation response to mechanical loading, enhanced expression of Wnt inhibitors, and suppressed Wnt signaling. At the same time, the enhancement of bone resorption by mechanical unloading was unaffected. Unexpectedly, IL-11-/- mice have increased systemic adiposity and glucose intolerance. Osteoblast/osteocyte-specific IL-11 deletion in osteocalcin-Cre;IL-11fl/fl mice have reduced serum IL-11 levels, blunted bone formation under mechanical loading, and increased systemic adiposity similar to IL-11-/- mice. Adipocyte-specific IL-11 deletion in adiponectin-Cre;IL-11fl/fl did not exhibit any abnormalities. We demonstrate that osteoblast/osteocyte-derived IL-11 controls both osteogenesis and systemic adiposity in response to mechanical loading, an important insight for our understanding of osteoporosis and metabolic syndromes.

Upregulation of OASIS/CREB3L1 in podocytes contributes to the disturbance of kidney homeostasis.

Podocyte injury is involved in the onset and progression of various kidney diseases. We previously demonstrated that the transcription factor, old astrocyte specifically induced substance (OASIS) in myofibroblasts, contributes to kidney fibrosis, as a novel role of OASIS in the kidneys. Importantly, we found that OASIS is also expressed in podocytes; however, the pathophysiological significance of OASIS in podocytes remains unknown. Upon lipopolysaccharide (LPS) treatment, there is an increase in OASIS in murine podocytes. Enhanced serum creatinine levels and tubular injury, but not albuminuria and podocyte injury, are attenuated upon podocyte-restricted OASIS knockout in LPS-treated mice, as well as diabetic mice. The protective effects of podocyte-specific OASIS deficiency on tubular injury are mediated by protein kinase C iota (PRKCI/PKCι), which is negatively regulated by OASIS in podocytes. Furthermore, podocyte-restricted OASIS transgenic mice show tubular injury and tubulointerstitial fibrosis, with severe albuminuria and podocyte degeneration. Finally, there is an increase in OASIS-positive podocytes in the glomeruli of patients with minimal change nephrotic syndrome and diabetic nephropathy. Taken together, OASIS in podocytes contributes to podocyte and/or tubular injury, in part through decreased PRKCI. The induction of OASIS in podocytes is a critical event for the disturbance of kidney homeostasis.

Improvement in image quality via the pseudo confocal effect in multidirectional digital scanned laser light-sheet microscopy.

Multidirectional digital scanned laser light-sheet microscopy (mDSLM) cannot be used with the current pseudo confocal system to reduce blurring and background signals. The multiline scanning for light-sheet illumination and the simple image construction proposed in this study are alternative to the pseudo confocal system. We investigate the effectiveness of our pseudo confocal method combined with mDSLM on artificial phantoms and biological samples. The results indicate that image quality from mDSLM can be improved by the confocal effect; their combination is effective and can be applied to biological investigations.

Induction of Gastric Cancer by Successive Oncogenic Activation in the Corpus.

BACKGROUND & AIMS: Metaplasia and dysplasia in the corpus are reportedly derived from de-differentiation of chief cells. However, the cellular origin of metaplasia and cancer remained uncertain. Therefore, we investigated whether pepsinogen C (PGC) transcript-expressing cells represent the cellular origin of metaplasia and cancer using a novel Pgc-specific CreERT2 recombinase mouse model. METHODS: We generated a Pgc-mCherry-IRES-CreERT2 (Pgc-CreERT2) knock-in mouse model. Pgc-CreERT2/+ and Rosa-EYFP mice were crossed to generate Pgc-CreERT2/Rosa-EYFP (Pgc-CreERT2/YFP) mice. Gastric tissues were collected, followed by lineage-tracing experiments and histologic and immunofluorescence staining. We further established Pgc-CreERT2;KrasG12D/+ mice and investigated whether PGC transcript-expressing cells are responsible for the precancerous state in gastric glands. To investigate cancer development from PGC transcript-expressing cells with activated Kras, inactivated Apc, and Trp53 signaling pathways, we crossed Pgc-CreERT2/+ mice with conditional KrasG12D, Apcflox, Trp53flox mice. RESULTS: Expectedly, mCherry mainly labeled chief cells in the Pgc-CreERT2 mice. However, mCherry was also detected throughout the neck cell and isthmal stem/progenitor regions, albeit at lower levels. In the Pgc-CreERT2;KrasG12D/+ mice, PGC transcript-expressing cells with KrasG12D/+ mutation presented pseudopyloric metaplasia. The early induction of proliferation at the isthmus may reflect the ability of isthmal progenitors to react rapidly to Pgc-driven KrasG12D/+ oncogenic mutation. Furthermore, Pgc-CreERT2;KrasG12D/+;Apcflox/flox mice presented intramucosal dysplasia/carcinoma and Pgc-CreERT2;KrasG12D/+;Apcflox/flox;Trp53flox/flox mice presented invasive and metastatic gastric carcinoma. CONCLUSIONS: The Pgc-CreERT2 knock-in mouse is an invaluable tool to study the effects of successive oncogenic activation in the mouse corpus. Time-course observations can be made regarding the responses of isthmal and chief cells to oncogenic insults. We can observe stomach-specific tumorigenesis from the beginning to metastatic development.

NeuroGT: A brain atlas of neurogenic tagging CreER drivers for birthdate-based classification and manipulation of mouse neurons.

Neuronal birthdate is one of the major determinants of neuronal phenotypes. However, most birthdating methods are retrospective in nature, allowing very little experimental access to the classified neuronal subsets. Here, we introduce four neurogenic tagging mouse lines, which can assign CreER-loxP recombination to neuron subsets that share the same differentiation timing in living animals and enable various experimental manipulations of the classified subsets. We constructed a brain atlas of the neurogenic tagging mouse lines (NeuroGT), which includes holistic image data of the loxP-recombined neurons and their processes across the entire brain that were tagged on each single day during the neurodevelopmental period. This image database, which is open to the public, offers investigators the opportunity to find specific neurogenic tagging driver lines and the stages of tagging appropriate for their own research purposes.

Optineurin defects cause TDP43-pathology with autophagic vacuolar formation.

We previously showed that optineurin (OPTN) mutations lead to the development of amyotrophic lateral sclerosis. The association between OPTN mutations and the pathogenesis of amyotrophic lateral sclerosis remains unclear. To investigate the mechanism underlying its pathogenesis, we generated Optn knockout mice. We evaluated histopathological observations of these mice and compared with those of OPTN- amyotrophic lateral sclerosis cases to investigate the mechanism underlying the pathogenesis of amyotrophic lateral sclerosis caused by OPTN mutations. The Optn (-/-) mice presented neuronal autophagic vacuoles immunopositive for charged multivesicular body protein 2b, one of the hallmarks of granulovacuolar degenerations, in the cytoplasm of spinal cord motor neurons at the age of 8 months and the OPTN- amyotrophic lateral sclerosis case with homozygous Q398X mutation. In addition, Optn (-/-) mice showed TAR-DNA binding protein 43/sequestosome1/p62 -positive cytoplasmic inclusions and the clearance of nuclear TAR-DNA binding protein 43. The axonal degeneration of the sciatic nerves was observed in Optn (-/-) mice. However, we could not observe significant differences in survival time, body weight, and motor functions, at 24 months. Our findings suggest that homozygous OPTN deletion or mutations might result in autophagic dysfunction and TAR-DNA binding protein 43 mislocalization, thereby leading to neurodegeneration of motor neurons. These findings indicate that the Optn (-/-) mice recapitulate both common and specific pathogenesis of amyotrophic lateral sclerosis associated with autophagic abnormalities. Optn (-/-) mice could serve as a mouse model for the development of therapeutic strategies.

Endfoot regeneration restricts radial glial state and prevents translocation into the outer subventricular zone in early mammalian brain development.

Neural stem cells, called radial glia, maintain epithelial structure during the early neocortical development. The prevailing view claims that when radial glia first proliferate, their symmetric divisions require strict spindle orientation; its perturbation causes precocious neurogenesis and apoptosis. Here, we show that despite this conventional view, radial glia at the proliferative stage undergo normal symmetric divisions by regenerating an apical endfoot even if it is lost by oblique divisions. We found that the Notch-R-Ras-integrin ß1 pathway promotes the regeneration of endfeet, whose leading edge bears ectopic adherens junctions and the Par-polarity complex. However, this regeneration ability gradually declines during the subsequent neurogenic stage and hence oblique divisions induce basal translocation of radial glia to form the outer subventricular zone, a hallmark of the development of the convoluted brain. Our study reveals that endfoot regeneration is a temporally changing cryptic property, which controls the radial glial state and its shift is essential for mammalian brain size expansion.

Deficiency of Cardiac Natriuretic Peptide Signaling Promotes Peripartum Cardiomyopathy-Like Remodeling in the Mouse Heart.

BACKGROUND: The maternal circulatory system and hormone balance both change dynamically during pregnancy, delivery, and the postpartum period. Although atrial natriuretic peptides and brain natriuretic peptides produced in the heart control circulatory homeostasis through their common receptor, NPR1, the physiologic and pathophysiologic roles of endogenous atrial natriuretic peptide/brain natriuretic peptide in the perinatal period are not fully understood. METHODS: To clarify the physiologic and pathophysiologic roles of the endogenous atrial natriuretic peptide/brain natriuretic peptide-NPR1 system during the perinatal period, the phenotype of female wild-type and conventional or tissue-specific Npr1-knockout mice during the perinatal period was examined, especially focusing on maternal heart weight, blood pressure, and cardiac function. RESULTS: In wild-type mice, lactation but not pregnancy induced reversible cardiac hypertrophy accompanied by increases in fetal cardiac gene mRNAs and ERK1/2 (extracellular signaling-regulated kinase) phosphorylation. Npr1-knockout mice exhibited significantly higher plasma aldosterone level than did wild-type mice, severe cardiac hypertrophy accompanied by fibrosis, and left ventricular dysfunction in the lactation period. Npr1-knockout mice showed a high mortality rate over consecutive pregnancy-lactation cycles. In the hearts of Npr1-knockout mice during or after the lactation period, an increase in interleukin-6 mRNA expression, phosphorylation of signal transducer and activator of transcription 3, and activation of the calcineurin-nuclear factor of the activated T cells pathway were observed. Pharmacologic inhibition of the mineralocorticoid receptor or neuron-specific deletion of the mineralocorticoid receptor gene significantly ameliorated cardiac hypertrophy in lactating Npr1-knockout mice. Anti-interleukin-6 receptor antibody administration tended to reduce cardiac hypertrophy in lactating Npr1-knockout mice. CONCLUSIONS: These results suggest that the characteristics of lactation-induced cardiac hypertrophy in wild-type mice are different from exercise-induced cardiac hypertrophy, and that the endogenous atrial natriuretic peptide/brain natriuretic peptide-NPR1 system plays an important role in protecting the maternal heart from interleukin-6-induced inflammation and remodeling in the lactation period, a condition mimicking peripartum cardiomyopathy.

Critical role of CRAG, a splicing variant of centaurin-γ3/AGAP3, in ELK1-dependent SRF activation at PML bodies.

CRMP-5-associated GTPase (CRAG), a short splicing variant of centaurin-γ3/AGAP3, is predominantly expressed in the developing brain. We previously demonstrated that CRAG, but not centaurin-γ3, translocates to the nucleus and activates the serum response factor (SRF)-c-Fos pathway in cultured neuronal cells. However, the physiological relevance of CRAG in vivo is unknown. Here, we found that CRAG/centaurin-γ3-knockout mice showed intensively suppressed kainic acid-induced c-fos expression in the hippocampus. Analyses of molecular mechanisms underlying CRAG-mediated SRF activation revealed that CRAG has an essential role in GTPase activity, interacts with ELK1 (a co-activator of SRF), and activates SRF in an ELK1-dependent manner. Furthermore, CRAG and ELK1 interact with promyelocytic leukaemia bodies through SUMO-interacting motifs, which is required for SRF activation. These results suggest that CRAG plays a critical role in ELK1-dependent SRF-c-fos activation at promyelocytic leukaemia bodies in the developing brain.

A Novel Birthdate-Labeling Method Reveals Segregated Parallel Projections of Mitral and External Tufted Cells in the Main Olfactory System.

A fundamental strategy in sensory coding is parallel processing, whereby unique, distinct features of sensation are computed and projected to the central target in the form of submodal maps. It remains unclear, however, whether such parallel processing strategy is employed in the main olfactory system, which codes the complex hierarchical odor and behavioral scenes. A potential scheme is that distinct subsets of projection neurons in the olfactory bulb (OB) form parallel projections to the targets. Taking advantage of the observation that the distinct projection neurons develop at different times, we developed a Cre-loxP-based method that allows for birthdate-specific labeling of cell bodies and their axon projections in mice. This birthdate tag analysis revealed that the mitral cells (MCs) born in an early developmental stage and the external tufted cells (TCs) born a few days later form segregated parallel projections. Specifically, the latter subset converges the axons onto only two small specific targets, one of which, located at the anterolateral edge of the olfactory tubercle (OT), excludes widespread MC projections. This target is made up of neurons that express dopamine D1 but not D2 receptor and corresponds to the most anterolateral isolation of the CAP compartments (aiCAP) that were defined previously. This finding of segregated projections suggests that olfactory sensing does indeed involve parallel processing of functionally distinct submodalities. Importantly, the birthdate tag method used here may pave the way for deciphering the functional meaning of these individual projection pathways in the future.

Semaphorin 6A-Plexin A2/A4 Interactions with Radial Glia Regulate Migration Termination of Superficial Layer Cortical Neurons.

Precise regulation of neuronal migration termination is crucial for the establishment of brain cytoarchitectures. However, little is known about how neurons terminate migration. Here we focused on interactions between migrating cortical neurons and their substrates, radial glial (RG) cells, and analyzed the role of Plexin A2 and A4 (PlxnA2/A4) receptors and their repulsive ligand, Semaphorin 6A (Sema6A), for this process. In both PlxnA2/A4 double-knockout and Sema6A mutant mice, the outermost cortical plate neurons ectopically invade layer 1 at a stage when they should reach their destinations. PlxnA2/A4 proteins are abundantly expressed on their leading processes, whereas Sema6A mRNA is enriched in RG cell somata. Cell-targeted gene expression and conditional knockouts indicate critical roles for these molecules. We hypothesize that the timely appearance of repulsive signaling mediated by Sema6A-PlxnA2/A4 weakens migrating neuron-RG cell interactions, leading to migration termination.

The putative Neuronatin imprint control region is an enhancer that also regulates the Blcap gene.

AIM: To investigate the regulatory potential of the Nnat second intron within the Nnat/Blcap micro-imprinted domain. MATERIALS & METHODS: Mice with deletion of Nnat second intron at the endogenous Nnat/Blcap micro-imprinted domain were used to examine the effect of Nnat second intron on the transcriptional regulation of the Nnat and Blcap genes. RESULTS & CONCLUSION: Deletion of Nnat second intron affected Nnat expression in cis leading to the loss of Nnat expression from the active paternal allele. Nnat second intron was found to have the characteristics of an imprint control region including allele-specific DNA methylation and histone modifications and it also regulated the epigenetic profile of Nnat promoter by acting as an enhancer. Nnat second intron was also found to be regulating the expression of the Blcap transcripts.

Dynamic organelle localization and cytoskeletal reorganization during preimplantation mouse embryo development revealed by live imaging of genetically encoded fluorescent fusion proteins.

Live imaging is one of the most powerful technologies for studying the behaviors of cells and molecules in living embryos. Previously, we established a series of reporter mouse lines in which specific organelles are labeled with various fluorescent proteins. In this study, we examined the localizations of fluorescent signals during preimplantation development of these mouse lines, as well as a newly established one, by time-lapse imaging. Each organelle was specifically marked with fluorescent fusion proteins; fluorescent signals were clearly visible during the whole period of time-lapse observation, and the expression of the reporters did not affect embryonic development. We found that some organelles dramatically change their sub-cellular distributions during preimplantation stages. In addition, by crossing mouse lines carrying reporters of two distinct colors, we could simultaneously visualize two types of organelles. These results confirm that our reporter mouse lines can be valuable genetic tools for live imaging of embryonic development.

Blockade of NKG2D/NKG2D ligand interaction attenuated cardiac remodelling after myocardial infarction.

AIMS: Accumulating evidence demonstrates that cardiomyocyte death contributes to the onset and progression of heart failure (HF) after myocardial injury. Recent studies revealed that immune/inflammatory reactions play important roles in cardiovascular diseases. However, it remains unclear whether immunosurveillance system, which eliminates cytopathic cells, including infected or malignant cancer cells, is involved in cardiomyocyte death, though cardiomyocytes are exposed to pathological stresses during post-infarct remodelling. The aim of this study is to clarify the pathophysiological significance of Natural Killer Group 2 member D (NKG2D)/NKG2D ligand (NKG2DL)-mediated cell death in HF after myocardial infarction (MI). METHODS AND RESULTS: MI was generated by ligating left anterior descending artery in mice. The expression of NKG2D, NKG2DLs, especially Retinoic acid early induced transcript-1ɛ (Rae-1ɛ), perforin and granzyme B was concomitantly up-regulated after MI. Immunohistological analysis revealed that Rae-1 was expressed on the membranes of injured cardiomyocytes in the infarct and border area. The MI-induced increase of Rae-1 expression was suppressed in p53-/- mice and Rae-1 was induced by the overexpression of p53. We identified p53-binding sites in Rae-1ɛ gene promoter, by chromatin immunoprecipitation assay, indicating that Rae-1 expression was mediated partially through p53. Flow cytometric analysis indicated that NKG2D-expressing immune cells in the post-infarct myocardium were mainly γδT cells. The co-culture with γδT cells increased the frequency of apoptotic cells in the cultured cardiomyocytes. The blockade of NKG2D/NKG2DL interaction by intraperitoneal injection of anti-Rae-1ɛ antibody after MI reduced the frequency of apoptotic cardiomyocytes, accompanied by suppression of cardiac fibrosis, attenuating cardiac dysfunction. Finally, tamoxifen-inducible cardiomyocyte-specific Rae-1ɛ overexpressing mice exhibited the susceptibility to post-infarct remodelling with increased cardiomyocyte apoptosis and severer cardiac dysfunction. CONCLUSION: The interaction between immune cells and cardiomyocytes via NKG2D/NKG2DL induces cardiomyocyte death, exacerbating cardiac remodelling after MI. The blockade of NKG2D/NKG2DL interaction could be a promising therapeutic strategy against HF.

ChIP-Atlas: a data-mining suite powered by full integration of public ChIP-seq data.

We have fully integrated public chromatin chromatin immunoprecipitation sequencing (ChIP-seq) and DNase-seq data (n > 70,000) derived from six representative model organisms (human, mouse, rat, fruit fly, nematode, and budding yeast), and have devised a data-mining platform-designated ChIP-Atlas (http://chip-atlas.org). ChIP-Atlas is able to show alignment and peak-call results for all public ChIP-seq and DNase-seq data archived in the NCBI Sequence Read Archive (SRA), which encompasses data derived from GEO, ArrayExpress, DDBJ, ENCODE, Roadmap Epigenomics, and the scientific literature. All peak-call data are integrated to visualize multiple histone modifications and binding sites of transcriptional regulators (TRs) at given genomic loci. The integrated data can be further analyzed to show TR-gene and TR-TR interactions, as well as to examine enrichment of protein binding for given multiple genomic coordinates or gene names. ChIP-Atlas is superior to other platforms in terms of data number and functionality for data mining across thousands of ChIP-seq experiments, and it provides insight into gene regulatory networks and epigenetic mechanisms.

Obesity in Yap transgenic mice is associated with TAZ downregulation.

Obesity is characterized by an expansion of white adipose tissue (WAT) mass, which mainly consists of adipocytes. During the commitment and differentiation of adipocytes, PPARγ functions as a key transcriptional factor for adipogenesis, and is associated with its suppressive coregulator, TAZ. Previous studies have shown the importance of TAZ in adipogenesis using an in vitro model; however, the understanding of its role in adipogenesis in vivo remains limited. Here, we report a unique obese mouse model that is associated with TAZ downregulation, which arose from the overexpression of Yap, a Taz paralog. YAP activation facilitated Hippo signaling feedback, which induced a compensatory reduction in YAP, subsequently neutralizing its functional activity. This feedback also induced TAZ suppression and exclusion from the nucleus. In Yap transgenic mice, TAZ downregulation in adipose stem cells activated PPARγ, leading to their differentiation into mature adipocytes and consequently increased adipose tissue. These results highlight the in vivo necessity of TAZ for adipocyte commitment and differentiation, which could provide insight into anti-obesity therapeutics.

CAMSAP3 maintains neuronal polarity through regulation of microtubule stability.

The molecular mechanisms that guide each neuron to become polarized, forming a single axon and multiple dendrites, remain unknown. Here we show that CAMSAP3 (calmodulin-regulated spectrin-associated protein 3), a protein that regulates the minus-end dynamics of microtubules, plays a key role in maintaining neuronal polarity. In mouse hippocampal neurons, CAMSAP3 was enriched in axons. Although axonal microtubules were generally acetylated, CAMSAP3 was preferentially localized along a less-acetylated fraction of the microtubules. CAMSAP3-mutated neurons often exhibited supernumerary axons, along with an increased number of neurites having nocodazole-resistant/acetylated microtubules compared with wild-type neurons. Analysis using cell lines showed that CAMSAP3 depletion promoted tubulin acetylation, and conversely, mild overexpression of CAMSAP3 inhibited it, suggesting that CAMSAP3 works to retain nonacetylated microtubules. In contrast, CAMSAP2, a protein related to CAMSAP3, was detected along all neurites, and its loss did not affect neuronal polarity, nor did it cause increased tubulin acetylation. Depletion of α-tubulin acetyltransferase-1 (αTAT1), the key enzyme for tubulin acetylation, abolished CAMSAP3 loss-dependent multiple-axon formation. These observations suggest that CAMSAP3 sustains a nonacetylated pool of microtubules in axons, interfering with the action of αTAT1, and this process is important to maintain neuronal polarity.

The actin-organizing formin protein Fhod3 is required for postnatal development and functional maintenance of the adult heart in mice.

Cardiac development and function require actin-myosin interactions in the sarcomere, a highly organized contractile structure. Sarcomere assembly mediated by formin homology 2 domain-containing 3 (Fhod3), a member of formins that directs formation of straight actin filaments, is essential for embryonic cardiogenesis. However, the role of Fhod3 in the neonatal and adult stages has remained unknown. Here, we generated floxed Fhod3 mice to bypass the embryonic lethality of an Fhod3 knockout (KO). Perinatal KO of Fhod3 in the heart caused juvenile lethality at around day 10 after birth with enlarged hearts composed of severely impaired myofibrils, indicating that Fhod3 is crucial for postnatal heart development. Tamoxifen-induced conditional KO of Fhod3 in the adult heart neither led to lethal effects nor did it affect sarcomere structure and localization of sarcomere components. However, adult Fhod3-deleted mice exhibited a slight cardiomegaly and mild impairment of cardiac function, conditions that were sustained over 1 year without compensation during aging. In addition to these age-related changes, systemic stimulation with the α1-adrenergic receptor agonist phenylephrine, which induces sustained hypertension and hypertrophy development, induced expression of fetal cardiac genes that was more pronounced in adult Fhod3-deleted mice than in the control mice, suggesting that Fhod3 modulates hypertrophic changes in the adult heart. We conclude that Fhod3 plays a crucial role in both postnatal cardiac development and functional maintenance of the adult heart.