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991.
Sugai K Setsuko S Uchiyama K Murakami N Kato H Yoshimaru H 《American journal of botany》2012,99(2):e84-e87
? Premise of the study: Expressed sequence tag (EST)-derived microsatellite markers were developed for Elaeocarpus photiniifolia, an endemic taxon of the Bonin Islands. ? Methods and Results: Initially, a complementary DNA (cDNA) library was constructed by de novo pyrosequencing of total RNA extracted from a seedling. A total of 267 primer pairs were designed from the library. Of the 48 tested loci, 25 loci were polymorphic among 41 individuals representing the entire geographical range of the species, with the number of alleles per locus and expected heterozygosity ranging from two to 14 and 0.09 to 0.86, respectively. Most loci were transferable to a related species, E. sylvestris. ? Conclusions: The developed markers will be useful for evaluating the genetic structure of E. photiniifolia. 相似文献
992.
993.
Nagamine S Tamba M Ishimine H Araki K Shiomi K Okada T Ohto T Kunita S Takahashi S Wismans RG van Kuppevelt TH Masu M Keino-Masu K 《The Journal of biological chemistry》2012,287(12):9579-9590
Heparan sulfate endosulfatases Sulf1 and Sulf2 hydrolyze 6-O-sulfate in heparan sulfate, thereby regulating cellular signaling. Previous studies have revealed that Sulfs act predominantly on UA2S-GlcNS6S disaccharides and weakly on UA-GlcNS6S disaccharides. However, the specificity of Sulfs and their role in sulfation patterning of heparan sulfate in vivo remained unknown. Here, we performed disaccharide analysis of heparan sulfate in Sulf1 and Sulf2 knock-out mice. Significant increases in ΔUA2S-GlcNS6S were observed in the brain, small intestine, lung, spleen, testis, and skeletal muscle of adult Sulf1(-/-) mice and in the brain, liver, kidney, spleen, and testis of adult Sulf2(-/-) mice. In addition, increases in ΔUA-GlcNS6S were seen in the Sulf1(-/-) lung and small intestine. In contrast, the disaccharide compositions of chondroitin sulfate were not primarily altered, indicating specificity of Sulfs for heparan sulfate. For Sulf1, but not for Sulf2, mRNA expression levels in eight organs of wild-type mice were highly correlated with increases in ΔUA2S-GlcNS6S in the corresponding organs of knock-out mice. Moreover, overall changes in heparan sulfate compositions were greater in Sulf1(-/-) mice than in Sulf2(-/-) mice despite lower levels of Sulf1 mRNA expression, suggesting predominant roles of Sulf1 in heparan sulfate desulfation and distinct regulation of Sulf activities in vivo. Sulf1 and Sulf2 mRNAs were differentially expressed in restricted types of cells in organs, and consequently, the sulfation patterns of heparan sulfate were locally and distinctly altered in Sulf1 and Sulf2 knock-out mice. These findings indicate that Sulf1 and Sulf2 differentially contribute to the generation of organ-specific sulfation patterns of heparan sulfate. 相似文献
994.
Michiko Yamasaki-Mann Angelo Demuro Ian Parker 《The Journal of biological chemistry》2010,285(32):25053-25061
In addition to its well established function in activating Ca2+ release from the endoplasmic reticulum (ER) through ryanodine receptors (RyR), the second messenger cyclic ADP-ribose (cADPR) also accelerates the activity of SERCA pumps, which sequester Ca2+ into the ER. Here, we demonstrate a potential physiological role for cADPR in modulating cellular Ca2+ signals via changes in ER Ca2+ store content, by imaging Ca2+ liberation through inositol trisphosphate receptors (IP3R) in Xenopus oocytes, which lack RyR. Oocytes were injected with the non-metabolizable analog 3-deaza-cADPR, and cytosolic [Ca2+] was transiently elevated by applying voltage-clamp pulses to induce Ca2+ influx through expressed plasmalemmal nicotinic channels. We observed a subsequent potentiation of global Ca2+ signals evoked by strong photorelease of IP3, and increased numbers of local Ca2+ puffs evoked by weaker photorelease. These effects were not evident with cADPR alone or following cytosolic Ca2+ elevation alone, indicating that they did not arise through direct actions of cADPR or Ca2+ on the IP3R, but likely resulted from enhanced ER store filling. Moreover, the appearance of a new population of puffs with longer latencies, prolonged durations, and attenuated amplitudes suggests that luminal ER Ca2+ may modulate IP3R function, in addition to simply determining the size of the available store and the electrochemical driving force for release. 相似文献
995.
996.
This study was aimed to compare the variations in cerebral oxygenation, blood pressure and center-of-foot pressure after standing from sitting and supine positions at normal (22 degrees C) and high (32 degrees C) room temperatures. Thirty young adults stood up from a resting posture (sitting or supine position) and kept the static standing posture for 90 sec. Meanwhile, their center-of-foot pressure (COP), blood pressure, and cerebral oxygenation kinetics were measured in continuity. The change of the frequency domain low-to-high frequency (LF/HF) ratio of the R-R interval before and after standing from a supine position was significantly higher than that from a sitting position under both temperature conditions. Blood pressure as well as total and oxygenated hemoglobin levels decreased immediately after standing up and the ratio of blood pressure change when moving from a supine position to standing at high room temperature was the largest as compared with the other conditions. Total hemoglobin (Hb) volume was found to temporarily decrease after standing and required 22-24 sec to recover when the subject started from the sitting position and 33-36 sec when the subject started from the supine position. Cerebral oxygenation kinetics tended to be larger under high, rather than normal, temperature conditions. All COP parameters after standing were significantly larger in the high temperature condition than in the normal temperature condition. Body sway after standing was larger in the high temperature condition than in the normal temperature condition and after standing from a supine position than from a sitting position. In conclusion, cerebral oxygenation kinetics and blood pressure measured after the subject moved to the standing position changed dramatically under high temperature conditions, and variations in this parameter may influence body sway. 相似文献
997.
Lilan Luo Sayuri Ando Yuki Sakamoto Takanori Suzuki Hiro Takahashi Nanako Ishibashi Shoko Kojima Daisuke Kurihara Tetsuya Higashiyama Kotaro T. Yamamoto Sachihiro Matsunaga Chiyoko Machida Michiko Sasabe Yasunori Machida 《The Plant journal : for cell and molecular biology》2020,101(5):1118-1134
In Arabidopsis, the ASYMMETRIC LEAVES2 (AS2) protein plays a key role in the formation of flat symmetric leaves via direct repression of the abaxial gene ETT/ARF3. AS2 encodes a plant‐specific nuclear protein that contains the AS2/LOB domain, which includes a z inc‐f inger (ZF) motif that is conserved in the AS2/LOB family. We have shown that AS2 binds to the coding DNA of ETT/ARF3, which requires the ZF motif. AS2 is co‐localized with AS1 in perinucleolar bodies (AS2 bodies). To identify the amino acid signals in AS2 required for formation of AS2 bodies and function(s) in leaf formation, we constructed recombinant DNAs that encoded mutant AS2 proteins fused to yellow fluorescent protein. We examined the subcellular localization of these proteins in cells of cotyledons and leaf primordia of transgenic plants and cultured cells. The amino acid signals essential for formation of AS2 bodies were located within and adjacent to the ZF motif. Mutant AS2 that failed to form AS2 bodies also failed to rescue the as2‐1 mutation. Our results suggest the importance of the formation of AS2 bodies and the nature of interactions of AS2 with its target DNA and nucleolar factors including NUCLEOLIN1. The partial overlap of AS2 bodies with perinucleolar chromocenters with condensed ribosomal RNA genes implies a correlation between AS2 bodies and the chromatin state. Patterns of AS2 bodies in cells during interphase and mitosis in leaf primordia were distinct from those in cultured cells, suggesting that the formation and distribution of AS2 bodies are developmentally modulated in plants. 相似文献
998.
Lukman Kevin Muhamad Uchiyama Yuta Quevedo Jay Mar D. Harding Diana Kohsaka Ryo 《Human ecology: an interdisciplinary journal》2021,49(5):551-564
Human Ecology - Understanding land-use change is imperative in the management of Indonesian coastal ecosystems with numerous environmental impacts generated from land-use conversion. To assess... 相似文献
999.
Mylène Vincent Erwann Philippe Amandine Everard Nadim Kassis Claude Rouch Jessica Denom Yorihiko Takeda Shoji Uchiyama Nathalie M. Delzenne Patrice D. Cani Stéphanie Migrenne Christophe Magnan 《Obesity (Silver Spring, Md.)》2013,21(3):553-561
Objective:
Dietary supplement may potentially help to fight obesity and other metabolic disorders such as insulin‐resistance and low‐grade inflammation. The present study aimed to test whether supplementation with Agaricus blazei murill (ABM) extract could have an effect on diet‐induced obesity in rats.Design and Methods:
Wistar rats were fed with control diet (CD) or high‐fat diet (HF) and either with or without supplemented ABM for 20 weeks.Results:
HF diet‐induced body weight gain and increased fat mass compared to CD. In addition HF‐fed rats developed hyperleptinemia and insulinemia as well as insulin resistance and glucose intolerance. In HF‐fed rats, visceral adipose tissue also expressed biomarkers of inflammation. ABM supplementation in HF rats had a protective effect against body weight gain and all study related disorders. This was not due to decreased food intake which remained significantly higher in HF rats whether supplemented with ABM or not compared to control. There was also no change in gut microbiota composition in HF supplemented with ABM. Interestingly, ABM supplementation induced an increase in both energy expenditure and locomotor activity which could partially explain its protective effect against diet‐induced obesity. In addition a decrease in pancreatic lipase activity is also observed in jejunum of ABM‐treated rats suggesting a decrease in lipid absorption.Conclusions:
Taken together these data highlight a role for ABM to prevent body weight gain and related disorders in peripheral targets independently of effect in food intake in central nervous system. 相似文献1000.
Nobumitsu Kobayashi Masayuki Hanaoka Yunden Droma Michiko Ito Yoshihiko Katsuyama Keishi Kubo Masao Ota 《PloS one》2013,8(8)