泛素蛋白酶体途径(ubiquitin-proteasome pathway,UPP)通过特异性降解目标蛋白调节细胞内蛋白水平及其功能,参与植物对正常生长发育信号和外界环境刺激的响应。SKP1-CUL1-F-box蛋白复合物是E3泛素连接酶的家族成员之一,该蛋白复合体能...泛素蛋白酶体途径(ubiquitin-proteasome pathway,UPP)通过特异性降解目标蛋白调节细胞内蛋白水平及其功能,参与植物对正常生长发育信号和外界环境刺激的响应。SKP1-CUL1-F-box蛋白复合物是E3泛素连接酶的家族成员之一,该蛋白复合体能够靶向识别并介导目标蛋白质的泛素化降解。作为SCF复合体的底物受体交换因子,CAND1(cullin-associated and neddylation-dissociated protein 1)动态调控SCF复合体的组装,在调控植物种子萌发、光形态建成、根系发育、叶脉模式、花器官发育和植物株型等方面发挥重要作用。本文综述了CAND1蛋白的研究历程及其结构与功能,为今后更深入地开展CAND1在植物生长发育中的功能研究提供参考。展开更多
Effects of earthworm casts on soil nutrient dynamics and their responses to changing moisture availability in subtropical ecosystems remain poorly understood.This study aimed to examine short-term carbon(C)and nitroge...Effects of earthworm casts on soil nutrient dynamics and their responses to changing moisture availability in subtropical ecosystems remain poorly understood.This study aimed to examine short-term carbon(C)and nitrogen(N)dynamics and their interactions with wetting-drying cycles in three different structural forms(i.e.,granular,globular,and heap-like)of Amynthas earthworm casts.The rates of C and N mineralization in the earthworm casts were examined under two different wetting-drying cycles(i.e.,2-d and 4-d wetting intervals)using a rainfall simulation experiment.After three simulated rainfall events,subsamples of the earthworm casts were further incubated for 4 d for the determination of CO2 and N2O fluxes.The results of this study indicated that the impacts of wetting-drying cycles on the short-term C and N dynamics were highly variable among the three cast forms,but wetting-drying cycles significantly reduced the cumulative CO2 and N2O fluxes by 62%-83%and 57%-85%,respectively,when compared to the control without being subjected to any rainfall events.The C mineralization rates in different cast forms were affected by the amount of organic substrates and N content in casts,which were associated with the food preference and selection of earthworms.Meanwhile,the cumulative N2O fluxes did not differ among the three cast forms.Repeated wetting and drying of casts not only enhanced aggregate stability by promoting bonds between the cast particles,but also inhibited microbial survival and growth during the prolonged drying period,which together hindered decomposition and denitrification.Our findings demonstrated that the interactions between the structural forms,aggregate dynamics,and C and N cycling in the earthworm casts were highly complex.展开更多
文摘泛素蛋白酶体途径(ubiquitin-proteasome pathway,UPP)通过特异性降解目标蛋白调节细胞内蛋白水平及其功能,参与植物对正常生长发育信号和外界环境刺激的响应。SKP1-CUL1-F-box蛋白复合物是E3泛素连接酶的家族成员之一,该蛋白复合体能够靶向识别并介导目标蛋白质的泛素化降解。作为SCF复合体的底物受体交换因子,CAND1(cullin-associated and neddylation-dissociated protein 1)动态调控SCF复合体的组装,在调控植物种子萌发、光形态建成、根系发育、叶脉模式、花器官发育和植物株型等方面发挥重要作用。本文综述了CAND1蛋白的研究历程及其结构与功能,为今后更深入地开展CAND1在植物生长发育中的功能研究提供参考。
基金We thank the Agriculture,Fisheries and Conservation Department of the Hong Kong SAR Government(China)for the permission of field sampling.
文摘Effects of earthworm casts on soil nutrient dynamics and their responses to changing moisture availability in subtropical ecosystems remain poorly understood.This study aimed to examine short-term carbon(C)and nitrogen(N)dynamics and their interactions with wetting-drying cycles in three different structural forms(i.e.,granular,globular,and heap-like)of Amynthas earthworm casts.The rates of C and N mineralization in the earthworm casts were examined under two different wetting-drying cycles(i.e.,2-d and 4-d wetting intervals)using a rainfall simulation experiment.After three simulated rainfall events,subsamples of the earthworm casts were further incubated for 4 d for the determination of CO2 and N2O fluxes.The results of this study indicated that the impacts of wetting-drying cycles on the short-term C and N dynamics were highly variable among the three cast forms,but wetting-drying cycles significantly reduced the cumulative CO2 and N2O fluxes by 62%-83%and 57%-85%,respectively,when compared to the control without being subjected to any rainfall events.The C mineralization rates in different cast forms were affected by the amount of organic substrates and N content in casts,which were associated with the food preference and selection of earthworms.Meanwhile,the cumulative N2O fluxes did not differ among the three cast forms.Repeated wetting and drying of casts not only enhanced aggregate stability by promoting bonds between the cast particles,but also inhibited microbial survival and growth during the prolonged drying period,which together hindered decomposition and denitrification.Our findings demonstrated that the interactions between the structural forms,aggregate dynamics,and C and N cycling in the earthworm casts were highly complex.
