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71.
Daniele De Barba Sergio Rossi Annie Deslauriers Hubert Morin 《Trees - Structure and Function》2016,30(1):87-97
Key message
In mature black spruce, bud burst process is anticipated by soil warming, while delayed by foliar applications of nitrogen; however, the effects depend on growth conditions at the site.Abstract
The observation of phenological events can be used as biological indicator of environmental changes, especially from the perspective of climate change. In boreal forests, the onset of the bud burst is a key factor in the length of the growing season. With current climate change, the major factors limiting the growth of boreal trees (i.e., temperature and nitrogen availability) are changing and studies on mature trees are limited. The aim of this study was to investigate the effects of soil warming and increased nitrogen (N) deposition on bud burst of mature black spruce [Picea mariana (Mill.) BSP]. From 2008 onwards, an experimental manipulation of these environmental growth conditions was conducted in two stands (BER and SIM) at different altitudes in the boreal forest of Quebec, Canada. An increase in soil temperature (H treatment) and a canopy application of artificial rain enriched with nitrogen (N treatment) were performed. Observations of bud phenology were made during May–July 2012 and 2013. In BER, H treatment caused an anticipation (estimated as 1–3 days); while N treatment, a delay (estimated as 1–2 days but only in 2012) in bud burst. No treatments effect was significant in SIM. It has been demonstrated that soil temperature and N availability can play an important role in affecting bud burst in black spruce but the effects of these environmental factors on growth are closely linked with site conditions.72.
Gray level Co‐occurrence Matrices (GLCM) to assess microstructural and textural changes in pre‐implantation embryos 下载免费PDF全文
73.
Chrystelle Aillaud Christophe Bosc Yasmina Saoudi Eric Denarier Leticia Peris Laila Sago Nicolas Taulet Adeline Cieren Olivia Tort Maria M. Magiera Carsten Janke Virginie Redeker Annie Andrieux Marie-Jo Moutin 《Molecular biology of the cell》2016,27(4):640-653
Cellular α-tubulin can bear various carboxy-terminal sequences: full-length tubulin arising from gene neosynthesis is tyrosinated, and two truncated variants, corresponding to detyrosinated and Δ2 α‑tubulin, result from the sequential cleavage of one or two C-terminal residues, respectively. Here, by using a novel antibody named 3EG that is highly specific to the –EEEG C-terminal sequence, we demonstrate the occurrence in neuronal tissues of a new αΔ3‑tubulin variant corresponding to α1A/B‑tubulin deleted of its last three residues (EEY). αΔ3‑tubulin has a specific distribution pattern: its quantity in the brain is similar to that of αΔ2-tubulin around birth but is much lower in adult tissue. This truncated α1A/B-tubulin variant can be generated from αΔ2-tubulin by the deglutamylases CCP1, CCP4, CCP5, and CCP6 but not by CCP2 and CCP3. Moreover, using 3EG antibody, we identify a C‑terminally truncated β-tubulin form with the same –EEEG C-terminal sequence. Using mass spectrometry, we demonstrate that β2A/B-tubulin is modified by truncation of the four C-terminal residues (EDEA). We show that this newly identified βΔ4-tubulin is ubiquitously present in cells and tissues and that its level is constant throughout the cell cycle. These new C-terminally truncated α- and β-tubulin variants, both ending with –EEEG sequence, are expected to regulate microtubule physiology. Of interest, the αΔ3-tubulin seems to be related to dynamic microtubules, resembling tyrosinated-tubulin rather than the other truncated variants, and may have critical function(s) in neuronal development. 相似文献
74.
Félix-Faure Jim Gaillard Jérémie Descloux Stéphane Chanudet Vincent Poirel Alain Baudoin Jean-Marc Avrillier Jean-Noël Millery Annie Dambrine Etienne 《Ecosystems》2019,22(2):312-330
Ecosystems - When a water reservoir is created, the pre-existing soils and vegetation are flooded. Here, we took advantage of the complete emptying of the Sarrans Reservoir, which was flooded... 相似文献
75.
Bulle Cécile Margni Manuele Patouillard Laure Boulay Anne-Marie Bourgault Guillaume De Bruille Vincent Cao Viêt Hauschild Michael Henderson Andrew Humbert Sebastien Kashef-Haghighi Sormeh Kounina Anna Laurent Alexis Levasseur Annie Liard Gladys Rosenbaum Ralph K. Roy Pierre-Olivier Shaked Shanna Fantke Peter Jolliet Olivier 《The International Journal of Life Cycle Assessment》2019,24(9):1653-1674
The International Journal of Life Cycle Assessment - This paper addresses the need for a globally regionalized method for life cycle impact assessment (LCIA), integrating multiple state-of-the-art... 相似文献
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77.
Alessandra Vigilante Anna Laddach Nathalie Moens Ruta Meleckyte Andreas Leha Arsham Ghahramani Oliver J. Culley Annie Kathuria Chloe Hurling Alice Vickers Erika Wiseman Mukul Tewary Peter W. Zandstra Richard Durbin Franca Fraternali Oliver Stegle Ewan Birney Fiona M. Watt 《Cell reports》2019,26(8):2078-2087.e3
78.
Baricault L Ségui B Guégand L Olichon A Valette A Larminat F Lenaers G 《Experimental cell research》2007,313(17):3800-3808
OPA1, an intra-mitochondrial dynamin GTPase, is a key actor of outer and inner mitochondrial membrane dynamic. OPA1 amino-terminal cleavage by PARL and m-AAA proteases was recently proposed to participate to the mitochondrial network dynamic in a DeltaPsi(m)-dependent way, and to apoptosis. Here, by an in vitro approach combining the use of purified mitochondrial fractions and mitochondrial targeting drugs, we intended to identify the central stimulus responsible for OPA1 cleavage. We confirm that apoptosis induction and PTPore opening, as well as DeltaPsi(m) dissipation induce OPA1 cleavage. Nevertheless, our experiments evidenced that decreased mitochondrial ATP levels, either generated by apoptosis induction, DeltaPsi(m) dissipation or inhibition of ATP synthase, is the common and crucial stimulus that controls OPA1 processing. In addition, we report that ectopic iron addition activates OPA1 cleavage, whereas zinc inhibits this process. These results suggest that the ATP-dependent OPA1 processing plays a central role in correlating the energetic metabolism to mitochondrial dynamic and might be involved in the pathophysiology of diseases associated to excess of iron or depletion of zinc and ATP. 相似文献
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