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31.
Jada Benn Torres Victoria Martucci Melinda C. Aldrich Miguel G. Vilar Taryn MacKinney Muhammad Tariq Jill B. Gaieski Ricardo Bharath Hernandez Zoila E. Browne Marlon Stevenson Wendell Walters Theodore G. Schurr The Genographic Consortium 《American journal of physical anthropology》2019,169(3):482-497
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Identification of signals for systemic adaption of hormonal regulation would help to understand the crosstalk between cells and environmental cues contributing to growth, metabolic homeostasis and development. Physiological states are controlled by precise pulsatile hormonal release, including endocrine steroids in human and ecdysteroids in insects. We show in Drosophila that regulation of genes that control biosynthesis and signaling of the steroid hormone ecdysone, a central regulator of developmental progress, depends on the extracellular matrix protein Obstructor-A (Obst-A). Ecdysone is produced by the prothoracic gland (PG), where sensory neurons projecting axons from the brain integrate stimuli for endocrine control. By defining the extracellular surface, Obst-A promotes morphogenesis and axonal growth in the PG. This process requires Obst-A-matrix reorganization by Clathrin/Wurst-mediated endocytosis. Our data identifies the extracellular matrix as essential for endocrine ring gland function, which coordinates physiology, axon morphogenesis, and developmental programs. As Obst-A and Wurst homologs are found among all arthropods, we propose that this mechanism is evolutionary conserved. 相似文献
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Faruqi SA Prescott HM Ali T Noumoff JS 《Journal of the Association of Genetic Technologists》2004,30(4):146-148
We have devised a new cell culture method where two types of culture plates made of normal tissue culture plastic (NTCP) and Primaria(TM), and two media, RPMI-1640 and a serum-free media LHC-9(TM), are used in combination with an in situ harvest. Multiple culture conditions in combination with in situ harvest has yielded many more clones for karyotyping than was possible with previous methods. Cells were cultured in 60 mm Petri plates instead of flasks and harvested in situ. Chromosome banding was performed using a highly purified trypsin "Enzar-T(TM)" and Leishman stain instead of ordinary trypsin and Giemsa stain. These modifications have increased the number of clones retrieved, rate of culture success, and quality of karyotypes in solid tumors. 相似文献
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Akash Tariq Kaiwen Pan Olusanya A Olatunji Corina Graciano Zilong Li Ningning Li Dagang Song Feng Sun Xiaogang Wu Mohammed A. Dakhil Xiaoming Sun Lin Zhang 《Physiologia plantarum》2019,166(4):894-908
Eucalyptus grandis is the most widely planted tree species worldwide and can face severe drought during the initial months after planting because the root system is developing. A complete randomized design was used to study the effects of two water regimes (well‐watered and water‐stressed) and phosphorus (P) applications (with and without P) on the morphological and physio‐biochemical responses of E. grandis. Drought had negative effects on the growth and metabolism of E. grandis, as indicated by changes in morphological traits, decreased net photosynthetic rates (Pn), pigment concentrations, leaf relative water contents (LRWCs), nitrogenous compounds, over‐production of reactive oxygen species (ROS) and higher lipid peroxidation. However, E. grandis showed effective drought tolerance strategies, such as reduced leaf area and transpiration rate (E), higher accumulation of soluble sugars and proline and a strong antioxidative enzyme system. P fertilization had positive effects on well‐watered seedlings due to improved growth and photosynthesis, which indicated the high P requirements during the initial E. grandis growth stage. In drought‐stressed seedlings, P application had no effects on the morphological traits, but it significantly improved the LRWC, Pn, quantum efficiency of photosystem II (Fv/Fm), chlorophyll pigments, nitrogenous compounds and reduced lipid peroxidation. P fertilization improved E. grandis seedling growth under well‐watered conditions but also ameliorated some leaf physiological traits under drought conditions. The effects of P fertilization are mainly due to the enhancement of plant N nutrition. Therefore, P can be used as a fertilizer to improve growth and production in the face of future climate change. 相似文献
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Protoplasma - Recently, a promising technique has come forward in field of radiation-agriculture in which the natural polysaccharides are modified into useful oligomers after depolymerization.... 相似文献