Desiccation tolerance is a crucial characteristic for desert moss surviving in arid regions. Desiccation procedure always induces amphiphiles transferring from the polar cytoplasm into lipid bodies. The behavior of am...Desiccation tolerance is a crucial characteristic for desert moss surviving in arid regions. Desiccation procedure always induces amphiphiles transferring from the polar cytoplasm into lipid bodies. The behavior of amphiphiles transferring can contribute to the enhancement of desiccation tolerance and the reduction of plasma membrane integrity simultaneously. The effects of amphiphiles partitioning into the lipid phase during water loss has been studied for pollen and seeds using electron paramagnetic resonance （EPR） spectroscopy. However, desiccation-tolerant high plants occur among mosses, several angiosperms and higher plants seeds or pollens. They have different strategies for survival in dehydration and rehydration. A desiccation-tolerant moss Tortula desertorurn was used to investigate the behaviors of amphiphilic molecules during drying by spin label technology. There are small amount of amphiphilic probes partitioning into membrane during moss leaves dehydration, comparing with that in higher plants. Cytoplasm viscosity changed from 1.14 into glass state only dehydration less than 60 min. Moss leaves lost plasma membrane integrity slightly,from 0.115 to 0.237, occurred simultaneously with amphiphiles partition. The results showed the more advantages of mosses than higher plants in adapting fast dehydration. We propose that EPR spin label is feasible for studying the amphiphiles partitioning mechanisms in membrane protection and damage for desiccation-tolerant mosses.展开更多
The earliest land plants faced a suite of abiotic stresses largely unknown to their aquatic algal ancestors. The descendants of these plants evolved two general mechanisms for survival in the relatively arid aerial en...The earliest land plants faced a suite of abiotic stresses largely unknown to their aquatic algal ancestors. The descendants of these plants evolved two general mechanisms for survival in the relatively arid aerial environment. While the vascular plants or ＇tracheophytes＇ developed tissue specializations to transport and retain water, the other main lineages of land plants, the bryophytes, retained a simple, nonvascular morphology. The bryophytes--mosses, hornworts, and liverworts--continually undergo a co-equilibration of their water content with the surrounding environment and rely to a great extent on intrinsic cellular mechanisms to mitigate damage due to water stress. This short review will focus on the cellular and molecular responses to dehydration and rehydration in mosses, and offer insights into general plant responses to water stress.展开更多
文摘耐旱苔藓植物常常单个个体矮小、生物量低,如何从细小的单个个体中有效提取总DNA是进一步开展居群遗传多样性研究的关键。本研究以古尔班通古特沙漠广泛分布的刺叶墙藓(Tortula desertorum)为对象,使用快速提取法、2×CTAB法及DNeasy plant mini kit试剂盒提取法等3种方法对刺叶墙藓单个个体的总DNA进行提取。结果表明,2×CTAB法提取的DNA纯度高,凝胶电泳显示无明显降解现象,适宜作为PCR扩增的模板。利用所提取的单个个体DNA为模板,建立了优化的RAPDI、SSR反应体系。
基金the National Natural Science Foundation of China （No.30371002）.
文摘Desiccation tolerance is a crucial characteristic for desert moss surviving in arid regions. Desiccation procedure always induces amphiphiles transferring from the polar cytoplasm into lipid bodies. The behavior of amphiphiles transferring can contribute to the enhancement of desiccation tolerance and the reduction of plasma membrane integrity simultaneously. The effects of amphiphiles partitioning into the lipid phase during water loss has been studied for pollen and seeds using electron paramagnetic resonance （EPR） spectroscopy. However, desiccation-tolerant high plants occur among mosses, several angiosperms and higher plants seeds or pollens. They have different strategies for survival in dehydration and rehydration. A desiccation-tolerant moss Tortula desertorurn was used to investigate the behaviors of amphiphilic molecules during drying by spin label technology. There are small amount of amphiphilic probes partitioning into membrane during moss leaves dehydration, comparing with that in higher plants. Cytoplasm viscosity changed from 1.14 into glass state only dehydration less than 60 min. Moss leaves lost plasma membrane integrity slightly,from 0.115 to 0.237, occurred simultaneously with amphiphiles partition. The results showed the more advantages of mosses than higher plants in adapting fast dehydration. We propose that EPR spin label is feasible for studying the amphiphiles partitioning mechanisms in membrane protection and damage for desiccation-tolerant mosses.
文摘The earliest land plants faced a suite of abiotic stresses largely unknown to their aquatic algal ancestors. The descendants of these plants evolved two general mechanisms for survival in the relatively arid aerial environment. While the vascular plants or ＇tracheophytes＇ developed tissue specializations to transport and retain water, the other main lineages of land plants, the bryophytes, retained a simple, nonvascular morphology. The bryophytes--mosses, hornworts, and liverworts--continually undergo a co-equilibration of their water content with the surrounding environment and rely to a great extent on intrinsic cellular mechanisms to mitigate damage due to water stress. This short review will focus on the cellular and molecular responses to dehydration and rehydration in mosses, and offer insights into general plant responses to water stress.
