Objective In kinesin-3,the neck coil correlates with the following segments to form an extended neck that contains a characteristic hinge diverse from a proline in KIF13B to a long flexible linker in KIF1A.The functio...Objective In kinesin-3,the neck coil correlates with the following segments to form an extended neck that contains a characteristic hinge diverse from a proline in KIF13B to a long flexible linker in KIF1A.The function of this neck hinge for controlling processive movement,however,remains unclear.Methods We made a series of modifications to the neck hinges of KIF13B and KIF1A and tested their movement using a single-molecule motility assay.Results In KIF13B,the insertion of flexible residues before or after the proline differentially impacts the processivity or velocity,while the removal of this proline increases the both.In KIF1A,the deletion of entire flexible neck hinge merely enhances the processivity.The engineering of these hinge-truncated necks of kinesin-3 into kinesin-1 similarly boosts the processive movement of kinesin-1.Conclusion The neck hinge in kinesin-3 controls its processive movement and proper modifications tune the motor motility,which provides a novel strategy to reshape the processive movement of kinesin motors.展开更多
To understand metabolic adaptations,the basal metabolic rate（BMR） of Mrs Hume＇s Pheasant（Syrmaticus humiae） and Elliot＇s Pheasant（Syrmaticus ellioti） were investigated.Metabolic rate（MR）,body temperature（Tb...To understand metabolic adaptations,the basal metabolic rate（BMR） of Mrs Hume＇s Pheasant（Syrmaticus humiae） and Elliot＇s Pheasant（Syrmaticus ellioti） were investigated.Metabolic rate（MR）,body temperature（Tb） and thermal conductance（C） were determined in both species at a temperatrue range of 5-35 ℃,respectively.Oxygen consumption was measured with a closed circuit respirometer.The thermal neutral zones（TNZ） were 24.5-31.6 ℃,and 23.0-29.2 ℃,respectively.With a temperature range of 5-35 ℃,Mrs Hume＇s Pheasant and Elliot＇s Pheasant could maintained stable Tb at a mean of（40.47±0.64） and（40.36±0.10） ℃,respectively.Mean BMRs within TNZs were（1.36±0.84） mLO2/（g.h） for Mrs Hume＇s Pheasant and（2.03±0.12） mLO2/（g.h） for Elliot＇s Pheasant,which were 77% and 86% of the expected value based on their body mass,respectively.Thermal conductance of Mrs Hume＇s Pheasant and Elliot＇s Pheasant were（0.12±0.01） and（0.17±0.01） mLO2/（g.h.℃）,below the lower critical temperature,respectively,which were 119% and 124% of the expected value based on their body mass,respectively.The ecophysiological characteristics of these species were low metabolic rate,high body temperature,and high thermal conductance,which allow both species to better adapt to the warmer climate environment in south China.展开更多
Hume's Pheasant(Syrmaticus humiae) and the Silver Pheasant(Lophura nycthemera) are two sympatric bird species at Dazhong Mountain of Yunnan Province,southwestern China.We investigated characteristics of roosting h...Hume's Pheasant(Syrmaticus humiae) and the Silver Pheasant(Lophura nycthemera) are two sympatric bird species at Dazhong Mountain of Yunnan Province,southwestern China.We investigated characteristics of roosting habitats of the two pheasants from February to April,2004 in this area.Multiple statistics,Matryoshka and a habitat classification-tree were used to analyze the selection of roosting habitats of these pheasants. The results of the habitat classification-tree indicated that several separations occurred in their macro and micro roosting habitats in the study area. The two pheasants had similar crucial requirements for and selection of ecological roosting factors,which allow them to live in the same macrohabitat.Competition between these two pheasants was avoided by separation of spatial elements,such as roosting trees and topographic characteristics.For safety strategy,Hume's Pheasant adopted primarily a way of'uneasily found habitat cover plus easy escape',while the Silver Pheasant employed a unique way of'uneasily found habitat cover'.For tactics of keeping warm,Hume's Pheasant selected mainly a method of'suitable vegetation supplemented with suitable topography',while the Silver Pheasant chose a unique man-ner of'suitable vegetation'.展开更多
Sex-biased dispersal,in which individuals of one sex tend to disperse and breed at a greater distance from their natal site than individuals of the opposite sex,appears to be common in vertebrate organisms and is very...Sex-biased dispersal,in which individuals of one sex tend to disperse and breed at a greater distance from their natal site than individuals of the opposite sex,appears to be common in vertebrate organisms and is very important to population structures and dynamics.Many studies have documented the dispersal patterns of monogamous birds; however,observations and data are few for polygynous birds.In our study,we report on the indication of sex-biased dispersal in Elliot's Pheasant (Syrmaticus ellioti),a vulnerable species endemic to China,using polymorphic DNA microsatellite loci (105 individual birds and seven loci) and mitochondrial DNA control-region sequences (63 birds).Contrary to the traditional concept that males are the more philopatric sex and females the more dispersing sex in birds,all the genetic information extracted from the two markers suggests that male-biased dispersal is predominant in Elliot's Pheasant.We argue that polygynous species in Galliformes without lekking behavior are more likely to exhibit male-biased dispersal patterns,consistent with the expected results based on the polygynous mating system of Elliot's Pheasant.展开更多
This study aimed to discuss the energy budget of Elliot's pheasant Syrmaticus ellioti in different seasons, with life and health, good growth and normal digestion of Elliot's pheasant as the tested objects, Th...This study aimed to discuss the energy budget of Elliot's pheasant Syrmaticus ellioti in different seasons, with life and health, good growth and normal digestion of Elliot's pheasant as the tested objects, The energy budget of Elliot's pheasant was measured by daily collection of the trial pheasants' excrement in the biological garden of Guangxi Normal University from March 2011 to February 2012. The results showed that the gross energy consumption, metabolic energy and excrement energy varied by season, increasing as temperature decreased. There was significant difference in gross energy consumption, metabolic energy, excrement energy between adults and nonages. There was also a trend that food digestibility of pheasants increases as temperature increases. In the same season, the food digestibility of adults was better than that of nonages. Throughout spring, summer, autumn and winter, the metabolic energy of 4-year adults were 305.77±13.40 kJ/d, 263.67±11.89 kJ/d, 357.23±25.49 kJ/d and 403.12±24.91 kJ/d, respectively, and the nonages were 284.86±17.22 kJ/d, 284. 66±15.16 kJ/d, 402. 26±31.46 kJ/d and 420. 30±31.98 kJ/d, respectively. The minimum metabolic energies were 247.65±21.81 g, 265.86±26.53 g, respectively for each group, detected between 4-year adults and 1-year nonages. Further study is needed to determine whether 29.6 C is the optimal temperature for the Elliot's pheasant.展开更多
文摘Objective In kinesin-3,the neck coil correlates with the following segments to form an extended neck that contains a characteristic hinge diverse from a proline in KIF13B to a long flexible linker in KIF1A.The function of this neck hinge for controlling processive movement,however,remains unclear.Methods We made a series of modifications to the neck hinges of KIF13B and KIF1A and tested their movement using a single-molecule motility assay.Results In KIF13B,the insertion of flexible residues before or after the proline differentially impacts the processivity or velocity,while the removal of this proline increases the both.In KIF1A,the deletion of entire flexible neck hinge merely enhances the processivity.The engineering of these hinge-truncated necks of kinesin-3 into kinesin-1 similarly boosts the processive movement of kinesin-1.Conclusion The neck hinge in kinesin-3 controls its processive movement and proper modifications tune the motor motility,which provides a novel strategy to reshape the processive movement of kinesin motors.
基金the National Natural Science Foundation of China (30760039)the Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University)Ministry of Education, China, and the projects of Science and Technology Bureau of Yongzhou, Hunan (201019)
文摘To understand metabolic adaptations,the basal metabolic rate（BMR） of Mrs Hume＇s Pheasant（Syrmaticus humiae） and Elliot＇s Pheasant（Syrmaticus ellioti） were investigated.Metabolic rate（MR）,body temperature（Tb） and thermal conductance（C） were determined in both species at a temperatrue range of 5-35 ℃,respectively.Oxygen consumption was measured with a closed circuit respirometer.The thermal neutral zones（TNZ） were 24.5-31.6 ℃,and 23.0-29.2 ℃,respectively.With a temperature range of 5-35 ℃,Mrs Hume＇s Pheasant and Elliot＇s Pheasant could maintained stable Tb at a mean of（40.47±0.64） and（40.36±0.10） ℃,respectively.Mean BMRs within TNZs were（1.36±0.84） mLO2/（g.h） for Mrs Hume＇s Pheasant and（2.03±0.12） mLO2/（g.h） for Elliot＇s Pheasant,which were 77% and 86% of the expected value based on their body mass,respectively.Thermal conductance of Mrs Hume＇s Pheasant and Elliot＇s Pheasant were（0.12±0.01） and（0.17±0.01） mLO2/（g.h.℃）,below the lower critical temperature,respectively,which were 119% and 124% of the expected value based on their body mass,respectively.The ecophysiological characteristics of these species were low metabolic rate,high body temperature,and high thermal conductance,which allow both species to better adapt to the warmer climate environment in south China.
基金financed by the Wildlife Conservation Program of the State Forestry Administration of China in 2009
文摘Hume's Pheasant(Syrmaticus humiae) and the Silver Pheasant(Lophura nycthemera) are two sympatric bird species at Dazhong Mountain of Yunnan Province,southwestern China.We investigated characteristics of roosting habitats of the two pheasants from February to April,2004 in this area.Multiple statistics,Matryoshka and a habitat classification-tree were used to analyze the selection of roosting habitats of these pheasants. The results of the habitat classification-tree indicated that several separations occurred in their macro and micro roosting habitats in the study area. The two pheasants had similar crucial requirements for and selection of ecological roosting factors,which allow them to live in the same macrohabitat.Competition between these two pheasants was avoided by separation of spatial elements,such as roosting trees and topographic characteristics.For safety strategy,Hume's Pheasant adopted primarily a way of'uneasily found habitat cover plus easy escape',while the Silver Pheasant employed a unique way of'uneasily found habitat cover'.For tactics of keeping warm,Hume's Pheasant selected mainly a method of'suitable vegetation supplemented with suitable topography',while the Silver Pheasant chose a unique man-ner of'suitable vegetation'.
基金supported by grants fromthe National Natural Science Foundation of China(30470232)
文摘Sex-biased dispersal,in which individuals of one sex tend to disperse and breed at a greater distance from their natal site than individuals of the opposite sex,appears to be common in vertebrate organisms and is very important to population structures and dynamics.Many studies have documented the dispersal patterns of monogamous birds; however,observations and data are few for polygynous birds.In our study,we report on the indication of sex-biased dispersal in Elliot's Pheasant (Syrmaticus ellioti),a vulnerable species endemic to China,using polymorphic DNA microsatellite loci (105 individual birds and seven loci) and mitochondrial DNA control-region sequences (63 birds).Contrary to the traditional concept that males are the more philopatric sex and females the more dispersing sex in birds,all the genetic information extracted from the two markers suggests that male-biased dispersal is predominant in Elliot's Pheasant.We argue that polygynous species in Galliformes without lekking behavior are more likely to exhibit male-biased dispersal patterns,consistent with the expected results based on the polygynous mating system of Elliot's Pheasant.
基金National Natural Science Foundation of China(31160426 30560023)the Projects of Science and Technology Office of Hunan (2011FJ3071)
文摘This study aimed to discuss the energy budget of Elliot's pheasant Syrmaticus ellioti in different seasons, with life and health, good growth and normal digestion of Elliot's pheasant as the tested objects, The energy budget of Elliot's pheasant was measured by daily collection of the trial pheasants' excrement in the biological garden of Guangxi Normal University from March 2011 to February 2012. The results showed that the gross energy consumption, metabolic energy and excrement energy varied by season, increasing as temperature decreased. There was significant difference in gross energy consumption, metabolic energy, excrement energy between adults and nonages. There was also a trend that food digestibility of pheasants increases as temperature increases. In the same season, the food digestibility of adults was better than that of nonages. Throughout spring, summer, autumn and winter, the metabolic energy of 4-year adults were 305.77±13.40 kJ/d, 263.67±11.89 kJ/d, 357.23±25.49 kJ/d and 403.12±24.91 kJ/d, respectively, and the nonages were 284.86±17.22 kJ/d, 284. 66±15.16 kJ/d, 402. 26±31.46 kJ/d and 420. 30±31.98 kJ/d, respectively. The minimum metabolic energies were 247.65±21.81 g, 265.86±26.53 g, respectively for each group, detected between 4-year adults and 1-year nonages. Further study is needed to determine whether 29.6 C is the optimal temperature for the Elliot's pheasant.
