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861.
Jun Yuan Lu Yu Ning Ling Waseem Raza Qirong Shen 《Biocontrol Science and Technology》2015,25(3):276-290
Biological control of plant soil-borne diseases has been shown as an attractive and an environment friendly alternative to chemical fungicides. Different microbial strains have been reported effective in controlling plant pathogens. Among those, Bacillus strains have their own importance. Bacillus amyloliquefaciens strain YL-25, isolated from the rhizosphere of healthy banana plant, was evaluated as bio-organic fertiliser (BIO) for its ability to promote plant growth and suppress Fusarium wilt of banana in pot experiment. The results showed that the application of the BIO containing strain YL-25 significantly promoted the growth of banana plants and decreased the incidence of Fusarium wilt compared to the organic fertiliser and chemical fertiliser (CF). In order to explore the beneficial mechanisms of strain YL-25, experiments were conducted in vitro. The phytohormones including indole-3-acetic acid and gibberellin A3 and stable antifungal compounds three homologous of iturin A were identified in the culture broth of strain YL-25. The strain YL-25 also showed the ability to degrade extracellular phytate in plate experiment. Owing to its innate multiple functional traits and biocontrol activity, the strain YL-25 may be used as plant-growth-promoting rhizobacterium and biocontrol agent against Fusarium wilt of banana. 相似文献
862.
Zhiqian Li Lang You Baosheng Zeng Lin Ling Jun Xu Xu Chen Zhongjie Zhang Subba Reddy Palli Yongping Huang Anjiang Tan 《Proceedings. Biological sciences / The Royal Society》2015,282(1809)
Metamorphosis in insects includes a series of programmed tissue histolysis and remolding processes that are controlled by two major classes of hormones, juvenile hormones and ecdysteroids. Precise pulses of ecdysteroids (the most active ecdysteroid is 20-hydroxyecdysone, 20E), are regulated by both biosynthesis and metabolism. In this study, we show that ecdysone oxidase (EO), a 20E inactivation enzyme, expresses predominantly in the midgut during the early pupal stage in the lepidopteran model insect, Bombyx mori. Depletion of BmEO using the transgenic CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/RNA-guided Cas9 nucleases) system extended the duration of the final instar larval stage. Ubiquitous transgenic overexpression of BmEO using the Gal4/UAS system induced lethality during the larval–pupal transition. When BmEO was specifically overexpressed in the middle silk gland (MSG), degeneration of MSG at the onset of metamorphosis was blocked. Transmission electron microscope and LysoTracker analyses showed that the autophagy pathway in MSG is inhibited by BmEO ectopic expression. Furthermore, RNA-seq analysis revealed that the genes involved in autophagic cell death and the mTOR signal pathway are affected by overexpression of BmEO. Taken together, BmEO functional studies reported here provide insights into ecdysone regulation of tissue degeneration during metamorphosis. 相似文献
863.
Crystal structure of human insulin‐regulated aminopeptidase with specificity for cyclic peptides
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Stefan J. Hermans David B. Ascher Nancy C. Hancock Jessica K. Holien Belinda J. Michell Siew Yeen Chai Craig J. Morton Michael W. Parker 《Protein science : a publication of the Protein Society》2015,24(2):190-199
Insulin‐regulated aminopeptidase (IRAP or oxytocinase) is a membrane‐bound zinc‐metallopeptidase that cleaves neuroactive peptides in the brain and produces memory enhancing effects when inhibited. We have determined the crystal structure of human IRAP revealing a closed, four domain arrangement with a large, mostly buried cavity abutting the active site. The structure reveals that the GAMEN exopeptidase loop adopts a very different conformation from other aminopeptidases, thus explaining IRAP's unique specificity for cyclic peptides such as oxytocin and vasopressin. Computational docking of a series of IRAP‐specific cognitive enhancers into the crystal structure provides a molecular basis for their structure–activity relationships and demonstrates that the structure will be a powerful tool in the development of new classes of cognitive enhancers for treating a variety of memory disorders such as Alzheimer's disease. 相似文献
864.
Genetic isolation between two recently diverged populations of a symbiotic fungus 总被引:1,自引:0,他引:1
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Sara Branco Pierre Gladieux Christopher E. Ellison Alan Kuo Kurt LaButti Anna Lipzen Igor V. Grigoriev Hui‐Ling Liao Rytas Vilgalys Kabir G. Peay John W. Taylor Thomas D. Bruns 《Molecular ecology》2015,24(11):2747-2758
Fungi are an omnipresent and highly diverse group of organisms, making up a significant part of eukaryotic diversity. Little is currently known about the drivers of fungal population differentiation and subsequent divergence of species, particularly in symbiotic, mycorrhizal fungi. Here, we investigate the population structure and environmental adaptation in Suillus brevipes (Peck) Kuntze, a wind‐dispersed soil fungus that is symbiotic with pine trees. We assembled and annotated the reference genome for Su. brevipes and resequenced the whole genomes of 28 individuals from coastal and montane sites in California. We detected two clearly delineated coast and mountain populations with very low divergence. Genomic divergence was restricted to few regions, including a region of extreme divergence containing a gene encoding for a membrane Na+/H+ exchanger known for enhancing salt tolerance in plants and yeast. Our results are consistent with a very recent split between the montane and coastal Su. brevipes populations, with few small genomic regions under positive selection and a pattern of dispersal and/or establishment limitation. Furthermore, we identify a putatively adaptive gene that motivates further functional analyses to link genotypes and phenotypes and shed light on the genetic basis of adaptive traits. 相似文献
865.
866.
Youjun Li Hao Zhou Fengzhi Li Siew Wee Chan Zhijie Lin Zhiyi Wei Zhou Yang Fusheng Guo Chun Jye Lim Wancai Xing Yuequan Shen Wanjin Hong Jiafu Long Mingjie Zhang 《Cell research》2015,25(7):801-817
The tumor suppressor Merlin/NF2 functions upstream of the core Hippo pathway kinases Lats1/2 and Mst1/2, as well as the nuclear E3 ubiquitin ligase CRL4DCAF1. Numerous mutations of Merlin have been identified in Neurofibromatosis type 2 and other cancer patients. Despite more than two decades of research, the upstream regulator of Merlin in the Hippo pathway remains unknown. Here we show by high-resolution crystal structures that the Lats1/2-binding site on the Merlin FERM domain is physically blocked by Merlin''s auto-inhibitory tail. Angiomotin binding releases the auto-inhibition and promotes Merlin''s binding to Lats1/2. Phosphorylation of Ser518 outside the Merlin''s auto-inhibitory tail does not obviously alter Merlin''s conformation, but instead prevents angiomotin from binding and thus inhibits Hippo pathway kinase activation. Cancer-causing mutations clustered in the angiomotin-binding domain impair angiomotin-mediated Merlin activation. Our findings reveal that angiomotin and Merlin respectively interface cortical actin filaments and core kinases in Hippo signaling, and allow construction of a complete Hippo signaling pathway. 相似文献
867.
Qian Jiang Stacey Arnold Tiffany Heanue Krishna?Praneeth Kilambi Betty Doan Ashish Kapoor Albee?Yun Ling Maria?X. Sosa Moltu Guy Qingguang Jiang Grzegorz Burzynski Kristen West Seneca Bessling Paola Griseri Jeanne Amiel Raquel?M. Fernandez Joke?B.G.M. Verheij Robert?M.W. Hofstra Salud Borrego Stanislas Lyonnet Isabella Ceccherini Jeffrey?J. Gray Vassilis Pachnis Andrew?S. McCallion Aravinda Chakravarti 《American journal of human genetics》2015,96(4):581-596
Innervation of the gut is segmentally lost in Hirschsprung disease (HSCR), a consequence of cell-autonomous and non-autonomous defects in enteric neuronal cell differentiation, proliferation, migration, or survival. Rare, high-penetrance coding variants and common, low-penetrance non-coding variants in 13 genes are known to underlie HSCR risk, with the most frequent variants in the ret proto-oncogene (RET). We used a genome-wide association (220 trios) and replication (429 trios) study to reveal a second non-coding variant distal to RET and a non-coding allele on chromosome 7 within the class 3 Semaphorin gene cluster. Analysis in Ret wild-type and Ret-null mice demonstrates specific expression of Sema3a, Sema3c, and Sema3d in the enteric nervous system (ENS). In zebrafish embryos, sema3 knockdowns show reduction of migratory ENS precursors with complete ablation under conjoint ret loss of function. Seven candidate receptors of Sema3 proteins are also expressed within the mouse ENS and their expression is also lost in the ENS of Ret-null embryos. Sequencing of SEMA3A, SEMA3C, and SEMA3D in 254 HSCR-affected subjects followed by in silico protein structure modeling and functional analyses identified five disease-associated alleles with loss-of-function defects in semaphorin dimerization and binding to their cognate neuropilin and plexin receptors. Thus, semaphorin 3C/3D signaling is an evolutionarily conserved regulator of ENS development whose dys-regulation is a cause of enteric aganglionosis. 相似文献
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870.