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61.
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Angel G. Hernandez Ana Rascon Shirley Kutner Henry Roman Zulaika Campos 《Molecular biology reports》1993,18(3):189-195
A correlation between the ratio of the cell surface protease activity to phosphatase activity and the complexity of the pattern of cell surface exposed polypeptides ofLeishmania promastigotes was demonstrated for various strains grown under similar conditions. The ratio of the cell surface protease activity to acid phosphatase activity was high forL. major andL.b. panamensis and it correlates with the expression of a single polypeptide of 63 KDa on their cell surface. Intermediate and lower ratios of these enzymatic activites relate with more complex radio-iodinated patterns: two main bands inL.b. guyanensis (70 and 58 KDa) andL.b. braziliensis (72 and 60 KDa) and three main bands 65, 50, 27 KDa in allL.m. mexicana strains tested. Evidence is presented that the acid phosphatase located on theL.m. mexicana cell surface is not an artifact due to a secondary absorption of the secreted acid phosphatase from the culture medium. These results confirm theLeishmania antigen cell surface heterogeneity. The implications on the biology ofLeishmania and the clinical manifestation of leishmaniasis are discussed. 相似文献
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Ana Buchadas Martin Jung Mercedes Bustamante Álvaro Fernández-Llamazares Stephen T. Garnett Ana Sofía Nanni Natasha Ribeiro Patrick Meyfroidt Tobias Kuemmerle 《Global Change Biology》2023,29(17):4880-4897
Tropical and subtropical dry woodlands are rich in biodiversity and carbon. Yet, many of these woodlands are under high deforestation pressure and remain weakly protected. Here, we assessed how deforestation dynamics relate to areas of woodland protection and to conservation priorities across the world's tropical dry woodlands. Specifically, we characterized different types of deforestation frontier from 2000 to 2020 and compared them to protected areas (PAs), Indigenous Peoples' lands and conservation areas for biodiversity, carbon and water. We found that global conservation priorities were always overrepresented in tropical dry woodlands compared to the rest of the globe (between 4% and 96% more than expected, depending on the type of conservation priority). Moreover, about 41% of all dry woodlands were characterized as deforestation frontiers, and these frontiers have been falling disproportionately in areas with important regional (i.e. tropical dry woodland) conservation assets. While deforestation frontiers were identified within all tropical dry woodland classes of woodland protection, they were lower than the average within protected areas coinciding with Indigenous Peoples' lands (23%), and within other PAs (28%). However, within PAs, deforestation frontiers have also been disproportionately affecting regional conservation assets. Many emerging deforestation frontiers were identified outside but close to PAs, highlighting a growing threat that the conserved areas of dry woodland will become isolated. Understanding how deforestation frontiers coincide with major types of current woodland protection can help target context-specific conservation policies and interventions to tropical dry woodland conservation assets (e.g. PAs in which deforestation is rampant require stronger enforcement, inactive deforestation frontiers could benefit from restoration). Our analyses also identify recurring patterns that can be used to test the transferability of governance approaches and promote learning across social–ecological contexts. 相似文献
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Neuza Domingues André R. A. Marques Rita Diogo Almeida Calado Inês S. Ferreira Cristiano Ramos José Ramalho Maria I. L. Soares Telmo Pereira Luís Oliveira José R. Vicente Louise H. Wong Inês C. M. Simões Teresa M. V. D. Pinho e Melo Andrew Peden Cláudia Guimas Almeida Clare E. Futter Rosa Puertollano Winchil L. C. Vaz Otília V. Vieira 《Traffic (Copenhagen, Denmark)》2023,24(7):284-307
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Julia E. J. Holm Sandro G. Soares Martyn F. Symmons Afiqah Saleh Huddin Martin C. Moncrieffe Nicholas J. Gay 《Traffic (Copenhagen, Denmark)》2023,24(11):508-521
Toll-Like Receptors (TLRs) play a pivotal role in immunity by recognising conserved structural features of pathogens and initiating the innate immune response. TLR signalling is subject to complex regulation that remains poorly understood. Here we show that two small type I transmembrane receptors, TMED2 and 7, that function as cargo sorting adaptors in the early secretory pathway are required for transport of TLRs from the ER to Golgi. Protein interaction studies reveal that TMED7 interacts with TLR2, TLR4 and TLR5 but not with TLR3 and TLR9. On the other hand, TMED2 interacts with TLR2, TLR4 and TLR3. Dominant negative forms of TMED7 suppress the export of cell surface TLRs from the ER to the Golgi. By contrast TMED2 is required for the ER-export of both plasma membrane and endosomal TLRs. Together, these findings suggest that association of TMED2 and TMED7 with TLRs facilitates anterograde transport from the ER to the Golgi. 相似文献