It would be well to note that in the absence of clear data about the formation of adaptation systems,or mechanisms of their occurrence,all that is recognized is the realization of the micro evolutionary processes.Ther...It would be well to note that in the absence of clear data about the formation of adaptation systems,or mechanisms of their occurrence,all that is recognized is the realization of the micro evolutionary processes.There is no well-defined connection between information exchange and formation展开更多
Realistic assessments of the impacts of global warming on population extinction risk are likely to require an integrated analysis of the roles of standing genetic variation,microhabitat thermal complexity,and the inte...Realistic assessments of the impacts of global warming on population extinction risk are likely to require an integrated analysis of the roles of standing genetic variation,microhabitat thermal complexity,and the inter-individual variation of heat tolerance due to both genetic differences and seasonal acclimatization effects.Here,we examine whether balancing selection and microhabitat temperature heterogeneity can interact to enhance the population persistence to thermal stress for the black mussel Septifer virgatus.We deployed biomimetic data loggers on the shore to measure the microhabitat-specific thermal variation from June 2014 to April 2016.Thermal tolerance of specimens was indexed by measuring effects of temperature on heart rate.Genotyping of specimens was performed using double digestion restriction association RADSeq(ddRADseq).Our results show that inter-individual variations in thermal tolerance correlate significantly with genetic differences at some specific gene loci,and that heterozygotes have higher thermal tolerances than homozygotes.The observed seasonal changes in genotype frequency suggest that these loci are under balancing selection.The ability of thermally resistant heterozygotes to survive in sun-exposed microhabitats acts to balance the loss of homozygotes during summer and enable the persistence of genetic polymorphisms.Population persistence of the mussel is also facilitated by the micro-scale variation in temperature,which provides refugia from thermal stress.Our results emphasize that inter-individual variation in thermal tolerance and in microhabitat heterogeneity in temperature are important for the persistence of populations in rocky shore habitats.展开更多
Thellungiella salsuginea （halophila） is a close relative of Arabidopsis thaliana but, unlike A. thaliana, it grows well in extreme conditions of cold, salt, and drought as well as nitrogen limitation. Over the last ...Thellungiella salsuginea （halophila） is a close relative of Arabidopsis thaliana but, unlike A. thaliana, it grows well in extreme conditions of cold, salt, and drought as well as nitrogen limitation. Over the last decade, many laboratories have started to use Thellungiella to investigate the physiological, metabolic, and molecular mechanisms of abiotic stress tolerance in plants, and new knowledge has been gained in particular with respect to ion transport and gene expression. The advantage of Thellungiella over other extremophile model plants is that it can be directly compared with Arabidopsis, and therefore generate information on both essential and critical components of stress tolerance. Thellungiella research is supported by a growing body of technical resources comprising physiological and molecular protocols, ecotype collections, expressed sequence tags, cDNA-libraries, microarrays, and a pending genome sequence. This review summarizes the current state of knowledge on Thellungiella and re-evaluates its usefulness as a model for research into plant stress tolerance.展开更多
文摘It would be well to note that in the absence of clear data about the formation of adaptation systems,or mechanisms of their occurrence,all that is recognized is the realization of the micro evolutionary processes.There is no well-defined connection between information exchange and formation
基金from National Natural Science Foundation of China(41776135,41976142)Nature Science funds for Distinguished Young Scholars of Fujian Province,China(2017J07003)to YWD.
文摘Realistic assessments of the impacts of global warming on population extinction risk are likely to require an integrated analysis of the roles of standing genetic variation,microhabitat thermal complexity,and the inter-individual variation of heat tolerance due to both genetic differences and seasonal acclimatization effects.Here,we examine whether balancing selection and microhabitat temperature heterogeneity can interact to enhance the population persistence to thermal stress for the black mussel Septifer virgatus.We deployed biomimetic data loggers on the shore to measure the microhabitat-specific thermal variation from June 2014 to April 2016.Thermal tolerance of specimens was indexed by measuring effects of temperature on heart rate.Genotyping of specimens was performed using double digestion restriction association RADSeq(ddRADseq).Our results show that inter-individual variations in thermal tolerance correlate significantly with genetic differences at some specific gene loci,and that heterozygotes have higher thermal tolerances than homozygotes.The observed seasonal changes in genotype frequency suggest that these loci are under balancing selection.The ability of thermally resistant heterozygotes to survive in sun-exposed microhabitats acts to balance the loss of homozygotes during summer and enable the persistence of genetic polymorphisms.Population persistence of the mussel is also facilitated by the micro-scale variation in temperature,which provides refugia from thermal stress.Our results emphasize that inter-individual variation in thermal tolerance and in microhabitat heterogeneity in temperature are important for the persistence of populations in rocky shore habitats.
文摘Thellungiella salsuginea （halophila） is a close relative of Arabidopsis thaliana but, unlike A. thaliana, it grows well in extreme conditions of cold, salt, and drought as well as nitrogen limitation. Over the last decade, many laboratories have started to use Thellungiella to investigate the physiological, metabolic, and molecular mechanisms of abiotic stress tolerance in plants, and new knowledge has been gained in particular with respect to ion transport and gene expression. The advantage of Thellungiella over other extremophile model plants is that it can be directly compared with Arabidopsis, and therefore generate information on both essential and critical components of stress tolerance. Thellungiella research is supported by a growing body of technical resources comprising physiological and molecular protocols, ecotype collections, expressed sequence tags, cDNA-libraries, microarrays, and a pending genome sequence. This review summarizes the current state of knowledge on Thellungiella and re-evaluates its usefulness as a model for research into plant stress tolerance.
