低温对麦红吸浆虫滞育解除及蜕皮激素受体基因EcR和热激蛋白基因Hsp70和Hsp90表达水平的影响

【目的】本研究旨在明确破茧率和破茧所需时间作为典型的专性幼虫期滞育昆虫麦红吸浆虫Sitodiplosis mosellana滞育解除指标的可行性,探讨蜕皮激素受体基因EcR和热激蛋白基因Hsp70和Hsp90在低温解除滞育中的作用。【方法】9月上旬采自田间的麦红吸浆虫滞育幼虫在低温(4℃)和自然变温处理不同时间(0~90 d)后转移至24℃化蛹,调查幼虫的破茧率、化蛹率及破茧和化蛹所需时间;采用qPCR技术分析4℃低温终止滞育并在24℃下恢复发育的幼虫EcR, Hsp70和Hsp90的mRNA水平。【结果】不同时间低温(4℃)和自然变温处理的麦红吸浆虫滞育幼虫破茧率和化蛹率以及破茧和化蛹所需时间均存在显著差异。未经低温(4℃)处理的幼虫在水分满足的条件下破茧率为71.3%,但均不能化蛹;低温(4℃)处理60 d内,随着处理时间的延长破茧率和化蛹率逐渐升高,破茧和化蛹所需时间逐渐缩短;与4℃低温处理30~60 d相比,自然变温处理30~60 d的幼虫化蛹率显著较低;4℃低温处理60 d和自然变温处理90 d后幼虫的化蛹率均超过91%。低温(4℃)处理显著提高了麦红吸浆虫幼虫EcR, Hsp70和Hsp90的表达量,其中处理30 d时其表达量最高,随着低温(4℃)处理时间的延长,表达量逐渐降低,大部分幼虫滞育解除后表达量趋于恒定。【结论】低温能显著促进麦红吸浆虫的滞育解除,效果优于9-10月自然变温;破茧率及破茧所需时间可作为评判麦红吸浆虫幼虫滞育强度的参考,但不能独立作为滞育解除的指标;EcR,Hsp70和Hsp90的表达水平与滞育强度密切相关,在麦红吸浆虫滞育解除中发挥潜在作用。     

NLRP3 regulates alveolar bone loss in ligature‐induced periodontitis by promoting osteoclastic differentiation

ObjectivesNLRP3 inflammasome is a critical part of the innate immune system and plays an important role in a variety of inflammatory diseases. However, the effects of NLRP3 inflammasome on periodontitis have not been fully studied.Materials and methodsWe used ligature‐induced periodontitis models of NLRP3 knockout mice (NLRP3^KO) and their wildtype (WT) littermates to compare their alveolar bone phenotypes. We further used Lysm‐Cre/Rosa^nTnG mouse to trace the changes of Lysm‐Cre⁺ osteoclast precursors in ligature‐induced periodontitis with or without MCC950 treatment. At last, we explored MCC950 as a potential drug for the treatment of periodontitis in vivo and in vitro.ResultsHere, we showed that the number of osteoclast precursors, osteoclast differentiation and alveolar bone loss were reduced in NLRP3^KO mice compared with WT littermates, by using ligature‐induced periodontitis model. Next, MCC950, a specific inhibitor of the NLRP3 inflammasome, was used to inhibit osteoclast precursors differentiation into osteoclast. Further, we used Lysm‐Cre/Rosa^nTnG mice to demonstrate that MCC950 decreases the number of Lysm‐Cre⁺ osteoclast precursors in ligature‐induced periodontitis. At last, treatment with MCC950 significantly suppressed alveolar bone loss with reduced IL‐1β activation and osteoclast differentiation in ligature‐induced periodontitis.ConclusionOur findings reveal that NLRP3 regulates alveolar bone loss in ligature‐induced periodontitis by promoting osteoclastic differentiation.     

Fitness of F1 hybrids between 10 maternal wild soybean populations and transgenic soybean

Transgenic Research - The releasing of transgenic soybeans (Glycine max (L.) Merr.) into farming systems raises concerns that transgenes might escape from the soybeans via pollen into...     

The community structure of bird assemblages on urban strangler figs

Figs have been regarded as keystone plant resources that support diverse tropical vertebrate frugivore communities. Planting or conserving large fig trees, such as stranglers, have therefore been proposed for enhancing urban biodiversity. We compared the diversity and community structure of bird assemblages on strangler figs with non‐fig urban trees as well as between the fruiting and non‐fruiting fig trees in an urban setting in Singapore. The total bird abundance across all the fig trees when in fruit was 4.5‐fold higher than on non‐fig trees and 3.5‐fold higher than when the same fig trees were not fruiting, but only attracted two more species. On individual trees, after accounting for the presence of mistletoes, tree height, the area covered by buildings, road lane density, and the distance to natural vegetation, mean diversity was not different between non‐fig trees and fig trees when they were not in fruit. On the other hand, when fruiting, each fig tree on average had 1.4 more species, 3 more counts of non‐native birds, and 1.6 more counts of insectivorous birds than when not fruiting. There was significant compositional turnover between non‐fig trees and non‐fruiting fig trees, while community dispersion was significantly lower among fig trees in fruit. Our results demonstrate that fig trees provide fruit and non‐fruit resources for birds in an urban landscape but do not necessarily support more diverse total bird assemblages than non‐fig trees. Instead, bird communities on fruiting urban figs would be highly homogeneous and dominated by a few species. Abstract in Malay is available with online material.