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151.
Reeve W O'Hara G Chain P Ardley J Bräu L Nandesena K Tiwari R Malfatti S Kiss H Lapidus A Copeland A Nolan M Land M Ivanova N Mavromatis K Markowitz V Kyrpides N Melino V Denton M Yates R Howieson J 《Standards in genomic sciences》2010,2(1):66-76
Rhizobium leguminosarum bv trifolii is the effective nitrogen fixing microsymbiont of a diverse range of annual and perennial Trifolium (clover) species. Strain WSM2304 is an aerobic, motile, non-spore forming, Gram-negative rod, isolated from Trifolium polymorphum in Uruguay in 1998. This microsymbiont predominated in the perennial grasslands of Glencoe Research Station, in Uruguay, to competitively nodulate its host, and fix atmospheric nitrogen. Here we describe the basic features of WSM2304, together with the complete genome sequence, and annotation. This is the first completed genome sequence for a nitrogen fixing microsymbiont of a clover species from the American center of origin. We reveal that its genome size is 6,872,702 bp encoding 6,643 protein-coding genes and 62 RNA only encoding genes. This multipartite genome was found to contain 5 distinct replicons; a chromosome of size 4,537,948 bp and four circular plasmids of size 1,266,105 bp, 501,946 bp, 308,747 bp and 257,956 bp. 相似文献
152.
Ralston SH Uitterlinden AG Brandi ML Balcells S Langdahl BL Lips P Lorenc R Obermayer-Pietsch B Scollen S Bustamante M Husted LB Carey AH Diez-Perez A Dunning AM Falchetti A Karczmarewicz E Kruk M van Leeuwen JP van Meurs JB Mangion J McGuigan FE Mellibovsky L del Monte F Pols HA Reeve J Reid DM Renner W Rivadeneira F van Schoor NM Sherlock RE Ioannidis JP;GENOMOS Investigators 《PLoS medicine》2006,3(4):e90
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Mechanical loading: biphasic osteocyte survival and targeting of osteoclasts for bone destruction in rat cortical bone 总被引:12,自引:0,他引:12
Noble BS Peet N Stevens HY Brabbs A Mosley JR Reilly GC Reeve J Skerry TM Lanyon LE 《American journal of physiology. Cell physiology》2003,284(4):C934-C943
Bone isremoved or replaced in defined locations by targeting osteoclasts andosteoblasts in response to its local history of mechanical loading.There is increasing evidence that osteocytes modulate this targeting bytheir apoptosis, which is associated with locally increasedbone resorption. To investigate the role of osteocytes in the controlof loading-related modeling or remodeling, we studied the effects onosteocyte viability of short periods of mechanical loading applied tothe ulnae of rats. Loading, which produced peak compressive strains of0.003 or 0.004, was associated with a 78% reduction in theresorption surface at the midshaft. The same loading regimen resultedin a 40% relative reduction in osteocyte apoptosis at the samesite 3 days after loading compared with the contralateral side(P = 0.01). The proportion of osteocytes that wereapoptotic was inversely related to the estimated local strain(P < 0.02). In contrast, a single short period ofloading resulting in strains of 0.008 engendered both tissuemicrodamage and subsequent bone remodeling and was associated with aneightfold increase in the proportion of apoptotic osteocytes(P = 0.02) at 7 days. This increase in osteocyteapoptosis was transient and preceded both intracorticalremodeling and death of half of the osteocytes (P < 0.01). The data suggest that osteocytes might use their U-shapedsurvival response to strain as a mechanism to influence boneremodeling. We hypothesize that this relationship reflects a causalmechanism by which osteocyte apoptosis regulates bone'sstructural architecture. 相似文献
156.
ANKTM1, a TRP-like channel expressed in nociceptive neurons,is activated by cold temperatures 总被引:37,自引:0,他引:37
Story GM Peier AM Reeve AJ Eid SR Mosbacher J Hricik TR Earley TJ Hergarden AC Andersson DA Hwang SW McIntyre P Jegla T Bevan S Patapoutian A 《Cell》2003,112(6):819-829
Mammals detect temperature with specialized neurons in the peripheral nervous system. Four TRPV-class channels have been implicated in sensing heat, and one TRPM-class channel in sensing cold. The combined range of temperatures that activate these channels covers a majority of the relevant physiological spectrum sensed by most mammals, with a significant gap in the noxious cold range. Here, we describe the characterization of ANKTM1, a cold-activated channel with a lower activation temperature compared to the cold and menthol receptor, TRPM8. ANKTM1 is a distant family member of TRP channels with very little amino acid similarity to TRPM8. It is found in a subset of nociceptive sensory neurons where it is coexpressed with TRPV1/VR1 (the capsaicin/heat receptor) but not TRPM8. Consistent with the expression of ANKTM1, we identify noxious cold-sensitive sensory neurons that also respond to capsaicin but not to menthol. 相似文献
157.
Keire DA Vincent Wu S Diehl DL Chew P Ho FJ Davis MT Lee TD Shively JE Walsh JH Reeve JR 《Regulatory peptides》2003,113(1-3):115-124
Details of prohormone processing patterns are revealed by purification and characterization of molecular forms stored in the tissues where the hormones are expressed. Molecular forms of rat gastrin were purified from antral extracts by gel permeation, anion exchange, and reverse-phase HPLC. Amidated and glycine-extended gastrins were detected with specific antisera and their structures determined by mass spectrometry. In rats, the only form shorter than gastrin-17 observed contained 16 amino acids. These data suggest that two enzymes process the amino terminus of gastrin-17. Pyrrolidone carboxylic acid peptidase removes the amino terminal pyrrolidone carboxylic acid (pyroGlu), forming gastrin-16. In mammals other than rat, gastrin-16 is then cleaved by dipeptidyl peptidase IV to form gastrin-14. In rat, this reaction does not take place because of proline residues Pro(2)-Pro(3)- in gastrin-16. Gastrin-16 is found in sulfated and nonsulfated forms and comprises 28% of the total gastrin immunoreactivity. Glycine-extended forms of gastrin-16 and gastrin-17 comprises 45% of the total gastrin immunoreactivity. The sulfated forms of gastrin-16 and gastrin-17 bind to the CCK-B receptor transfected into CHO cells with 10-fold higher affinity than the nonsulfated forms of these peptides. Therefore, processing of rat progastrin may modulate the expression of gastrin biological activity. 相似文献
158.
A large-enrollment, undergraduate cellular biology lecture course is described whose primary goal is to help students acquire skill in the interpretation of experimental data. The premise is that this kind of analytical reasoning is not intuitive for most people and, in the absence of hands-on laboratory experience, will not readily develop unless instructional methods and examinations specifically designed to foster it are employed. Promoting scientific thinking forces changes in the roles of both teacher and student. We describe didactic strategies that include directed practice of data analysis in a workshop format, active learning through verbal and written communication, visualization of abstractions diagrammatically, and the use of ancillary small-group mentoring sessions with faculty. The implications for a teacher in reducing the breadth and depth of coverage, becoming coach instead of lecturer, and helping students to diagnose cognitive weaknesses are discussed. In order to determine the efficacy of these strategies, we have carefully monitored student performance and have demonstrated a large gain in a pre- and posttest comparison of scores on identical problems, improved test scores on several successive midterm examinations when the statistical analysis accounts for the relative difficulty of the problems, and higher scores in comparison to students in a control course whose objective was information transfer, not acquisition of reasoning skills. A novel analytical index (student mobility profile) is described that demonstrates that this improvement was not random, but a systematic outcome of the teaching/learning strategies employed. An assessment of attitudes showed that, in spite of finding it difficult, students endorse this approach to learning, but also favor curricular changes that would introduce an analytical emphasis earlier in their training. 相似文献
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