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91.
Denis Fabre Michael Dingkuhn Xinyou Yin Anne Clément-Vidal Sandrine Roques Armelle Soutiras Delphine Luquet 《Plant, cell & environment》2020,43(3):579-593
This study aimed to understand the response of photosynthesis and growth to e-CO2 conditions (800 vs. 400 μmol mol−1) of rice genotypes differing in source–sink relationships. A proxy trait called local C source–sink ratio was defined as the ratio of flag leaf area to the number of spikelets on the corresponding panicle, and five genotypes differing in this ratio were grown in a controlled greenhouse. Differential CO2 resources were applied either during the 2 weeks following heading (EXP1) or during the whole growth cycle (EXP2). Under e-CO2, low source–sink ratio cultivars (LSS) had greater gains in photosynthesis, and they accumulated less nonstructural carbohydrate in the flag leaf than high source–sink ratio cultivars (HSS). In EXP2, grain yield and biomass gain was also greater in LSS probably caused by their strong sink. Photosynthetic capacity response to e-CO2 was negatively correlated across genotypes with local C source–sink ratio, a trait highly conserved across environments. HSS were sink-limited under e-CO2, probably associated with low triose phosphate utilization (TPU) capacity. We suggest that the local C source–sink ratio is a potential target for selecting more CO2-responsive cultivars, pending validation for a broader genotypic spectrum and for field conditions. 相似文献
92.
Polarized vesicle sorting is essential not only for epithelial cell function but also for cell polarization and tissue morphogenesis. Endocytosis is a key determinant of the surface abundance of plasma membrane proteins and is highly regulated. In an important recent paper, Rodríguez‐Fraticelli et al ( 2015 ) identify a new player in apical endocytosis—a previously uncharacterized protein called Plasmolipin. They report not only its mechanism of action through binding to an epsin, but also highlight an essential role in regulating Notch signaling, which controls epithelial differentiation. 相似文献
93.
An evaluation of different methods for assessing eggshell pigmentation and pigment concentration using great tit eggs
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The striking variation in colour and maculation of bird eggs has fascinated biologists since centuries, and many hypotheses based on mechanical, physiological or signalling functions have been proposed for its evolution by natural and sexual selection. Protoporphyrin is the main eggshell pigment found in brown maculated eggs, and is assumed to function as a mediator of these selection processes. It is a precursor of heme with pro‐oxidant properties, and hence a link between brown maculation and female condition has been proposed and tested in a number of studies, albeit with contrasting results. A variety of different visual methods have been used to quantify outer eggshell pigmentation, which has been assumed to correspond to overall quantity of protoporphyrin in the shell. Yet, this relationship has rarely been tested. The aim of this study was to apply four commonly used methods to assess pigmentation in great tit eggs with protoporphyrin as the predominant eggshell pigment, and to compare the results of these methods. Specifically, we 1) ranked eggshell pigmentation by human naked eye, 2) applied a granularity approach and 3) measured spectrophotometric reflectance of eggshell pigments. Second, we estimated the relationship between outer eggshell pigmentation (i.e. estimated by three different methods above) and true protoporphyrin concentration deposited in the entire shell measured by HPLC. Among‐method estimates were significantly correlated for the traits describing pigment ‘darkness’ only. While the model including scores based on human naked eyes explained 16% of the variance of pigment concentration in the entire shell, spectrometry explained 27%, and the granularity approach explained 40%. Thus, the estimation of true pigment concentration in the entire shell from the visible outer side of the shell is most reliable with the granularity approach. It is relevant for studies where the maintenance of the integrity of the eggs is essential. 相似文献
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A survey of aphids was carried out during the period 2008-2011 in different regions of Algeria by collecting and identifying aphids and their host plants. Aphids were collected from 46 host plants. Forty-six species were reported including thirty-six species which were recorded for the first time in this country and thirty species which were recorded for the first time in the Maghreb (North Africa). This study extends the number of known Algerian aphid to 156 species. 相似文献
96.
Efferth Thomas Kadioglu Onat Saeed Mohamed E. M. Seo Ean-Jeong Mbaveng Armelle T. Kuete Victor 《Phytochemistry Reviews》2021,20(1):7-53
Phytochemistry Reviews - Multidrug resistance is a major factor causing the failure of cancer chemotherapy. Efflux pumps of the ATP-binding cassette (ABC) transporter family expel a large array of... 相似文献
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Aurélien Michau Ghislaine Guillemain Alexandra Grosfeld Sandrine Vuillaumier-Barrot Teddy Grand Mathilde Keck Sébastien L'Hoste Danielle Chateau Patricia Serradas Jacques Teulon Pascale De Lonlay Rapha?l Scharfmann Edith Brot-Laroche Armelle Leturque Maude Le Gall 《The Journal of biological chemistry》2013,288(43):31080-31092
The structure-function relationships of sugar transporter-receptor hGLUT2 coded by SLC2A2 and their impact on insulin secretion and β cell differentiation were investigated through the detailed characterization of a panel of mutations along the protein. We studied naturally occurring SLC2A2 variants or mutants: two single-nucleotide polymorphisms and four proposed inactivating mutations associated to Fanconi-Bickel syndrome. We also engineered mutations based on sequence alignment and conserved amino acids in selected domains. The single-nucleotide polymorphisms P68L and T110I did not impact on sugar transport as assayed in Xenopus oocytes. All the Fanconi-Bickel syndrome-associated mutations invalidated glucose transport by hGLUT2 either through absence of protein at the plasma membrane (G20D and S242R) or through loss of transport capacity despite membrane targeting (P417L and W444R), pointing out crucial amino acids for hGLUT2 transport function. In contrast, engineered mutants were located at the plasma membrane and able to transport sugar, albeit with modified kinetic parameters. Notably, these mutations resulted in gain of function. G20S and L368P mutations increased insulin secretion in the absence of glucose. In addition, these mutants increased insulin-positive cell differentiation when expressed in cultured rat embryonic pancreas. F295Y mutation induced β cell differentiation even in the absence of glucose, suggesting that mutated GLUT2, as a sugar receptor, triggers a signaling pathway independently of glucose transport and metabolism. Our results describe the first gain of function mutations for hGLUT2, revealing the importance of its receptor versus transporter function in pancreatic β cell development and insulin secretion. 相似文献
100.
Carole Fureix Haïfa Benhajali Séverine Henry Anaelle Bruchet Armelle Prunier Mohammed Ezzaouia Caroline Coste Martine Hausberger Rupert Palme Patrick Jego 《BMC veterinary research》2013,9(1):1-10