In order to measure the impact of changes in the marsh on breeding Red-crowned Cranes (Grus japonensis) and White-naped Cranes (G.vipio) in the Sanjiang Plain,we conducted a complete crane súrvey in each of the s...In order to measure the impact of changes in the marsh on breeding Red-crowned Cranes (Grus japonensis) and White-naped Cranes (G.vipio) in the Sanjiang Plain,we conducted a complete crane súrvey in each of the summers of 2007 and 2008,and obtained information on the changes in its marsh through interpretation of satellite images in 1986,1995,2000 and 2005.A comparison between the 1984 and 2008 census shows that:1) the number of Red-crowned Cranes remained stable at about 300 birds,while the number of White-naped Cranes increased markedly; 2) the estimates of nests of Red-crowned cranes are close to the numbers of 1984,while approximately 90％ of the nests of these two crane species were distributed over five national nature reserves (NNRs); 3) the two crane species became more concentrated in three regions,i.e.,the Fuyuan Delta,the middle reaches of the Naoli and Qixing rivers,and the Xingkai Lake wetlands,rather as formerly in six regions.The area of the marsh decreased by 45％ within the 20-year period from 1986 to 2005.The major loss of the marsh area was in the form of a conversion to paddy fields and dry land,which can be primarily attributed to direct human activity under various economic and policy drivers.The disappearance of cranes in the Dulu and Abuqin rivers was induced by large-scale agricultural development.The fragmentation into and isolation of small areas of the marsh became increasingly more serious,which resulted in unsuitable condtions for crane breeding in small patches of the marsh.The number of cranes declined from 1984-1995 but had recovered remarkably by 2008,which may be due to theestablishment of a system of nature reserves,in place since 2000.The land ownership of the reserve plays a key role in maintaining the integrity of the wetland ecosystem,especially in Sanjiang,Honghe,Naolihe and Qixinghe NNRs,which together accommodated approximately 80％ of the population of cranes.However,we did not discover any nests at all in the provincial and municipal reserves,which may be attributed to high human disturbances in these areas.In the end,we propose some recommendations on reserve management.展开更多
Egg water was used to induce acrosome reaction in mature sperm of Fenneropenaeus chinensis .Transmission electron microscope and SDS PAGE were used to study the ultrastructure and protein changes of the sperm in ...Egg water was used to induce acrosome reaction in mature sperm of Fenneropenaeus chinensis .Transmission electron microscope and SDS PAGE were used to study the ultrastructure and protein changes of the sperm in F.chinensis ,which has undergone acrosome reaction.The results demonstrated that the sperms from female thelycum could be induced acrosome reaction in vitro by egg water,which was a kind of egg jelly released from oocyte into seawater during oocyte activation.More than fifty percent of sperm finished acrosome reaction during the first 30 min, in vitro .The whole event consists of the retraction of the spike and acrosome exocytosis.Spike was retracted and fused to acrosome cap followed by the release of acrosome granules.When the original egg water was diluted 5 and 10 times,The diluted egg water also have the ability to induce sperm acrosome reaction,but the acrosome reaction rate is much lower than that of the original egg water in the same time.Capillary zone electrophoresis was used to detect the biochemical components of egg water.Egg water was composed of two different components,which were also demonstrated by SDS PAGE.The molecular weights of the two kinds of egg jellies are both about 200kDa.Gelatin substrate SDS PAGE results did not show any hydrolytic enzyme activity in egg water.After acrosome reaction,many sorts of proteins in sperm are degraded.When the reacted sperms were examined with gelatin substrate SDS PAGE,there were six major peptide bands with hydrolytic enzyme activity were detected.Their molecular weights are 200kDa,130 kDa,66 kDa,53 kDa,48 kDa and 41 kDa respectively.These hydrolases cannot be detected in the sperms before acrosome reaction.The acrosome reaction of Chinese shrimp, F.chinensis is much different to that of the sperm in the shrimp, Sicyonia ingentis ,which the acrosome reaction was clearly studied.There is not filament formation during the acrosome reaction in Chinese shrimp.The time of exocytosis in the sperm of Chinese shrimp is also much longer than that of the sperm of Sicyonia ingentis .展开更多
A cDNA, designated as rtSH3p13, was isolated from a rat testis cDNA library. It consists of 1463 bp nuclear acids,which encodes a protein of 312 amino acids and was assigned the GenBank accession number AF227439. The ...A cDNA, designated as rtSH3p13, was isolated from a rat testis cDNA library. It consists of 1463 bp nuclear acids,which encodes a protein of 312 amino acids and was assigned the GenBank accession number AF227439. The deduced rtSH3p13 protein is a truncated isoform of SH3p13 as a result of mRNA alternative splicing. It is mainly expressed in the rat testis, detected in spermatids at the steps 8-19 of spermiogenesis, and found around the acrosome. During postnatal development, rtSH3p13 appears on day 18 and reaches maximum on day 60. Further experimental results suggested that rtSH3p13 forms a complex with activated epidermal growth factor receptor (EGFR) and interacts with synaptojanin I. Surprisingly, similar to SH3 domain, the V region of rtSH3p13 also inhibits endocytosis in CHO cells.Our results reveal a link between an rtSH3p13-synaptojanin-clathrin complex-mediated formation of pits and the process of spermiogenesis.展开更多
Actin filaments (AFs) in un-fixed pollen tubes of Amaryllis vittata Ait were visualized after TRITC-phalloidin staining with DMSO as a permeabilising agent. Typically, strands or hundles of microfilaments (Mfs) were d...Actin filaments (AFs) in un-fixed pollen tubes of Amaryllis vittata Ait were visualized after TRITC-phalloidin staining with DMSO as a permeabilising agent. Typically, strands or hundles of microfilaments (Mfs) were distributed in the extreme tip as well as pollen tubes in a form of network.Fluorescent granules or circles of various sizes were frequently found that continued with the filamentous structures. In addition, a more brightly stained structure, possibly Mf organizing center, was observed. Treatment of pollen tubes with cytochalasin D(CD)for increasing time intervals (5-40 minutes) caused gradual reduction of strands until flurescent granules filled up the pollen tubes. Mcanwhile, cytoplasmie streaming was inhibited completely. Though closely associated with vegetative nuclei (VN) and generative cells (GC), AFs were not found in the cytoplasm of GC.Mg++concentration greatly affected the isolated Mfs.展开更多
A membrane protein was isolated from mouse sperm heads that had undergone acrosomal reaction induced by C2+ ionophore, A 23187, which, with a molecular weight of 77.6 kd, shows capability to block egg-sperm fusion. As...A membrane protein was isolated from mouse sperm heads that had undergone acrosomal reaction induced by C2+ ionophore, A 23187, which, with a molecular weight of 77.6 kd, shows capability to block egg-sperm fusion. As revealed by analysis usintg isotopic markers, this protein is one of the chief membrane proteins of inner acrosomal membrane or the outer membrane of equatorial segment and Post-acrosomal region; treatment of mouse sperms with 0.6 μg/ml of the Purified protein for 30 minutes reduced the sperm-egg fusion index by 51%.The above results led us to the conclusion that the protein is an active participant in sperm-egg fusion. The possible existence of sperm receptor on egg plasma membrane was discussed.展开更多
An organic layer prepared from the seed of Aceriphyllum rossii was studied to identify the active compounds for protein tyrosine phosphatase 1B（PTP1B） inhibition.Bioassay guided fractionation resulted in the isolati...An organic layer prepared from the seed of Aceriphyllum rossii was studied to identify the active compounds for protein tyrosine phosphatase 1B（PTP1B） inhibition.Bioassay guided fractionation resulted in the isolation of PTP1B inhibitory activity of triterpenes（1-4）.These four compounds were identified as aceriphyllic acid C（1）,aceriphyllic acid D（2）,aceriphyllic acid E（3） and aceriphyllic acid F（4）.The isolated 1-4 compounds inhibited PTP1B with IC50 values ranged from（2.1±1.5） μmol/L to（11.2±2.5） μmol/L.Kinetic analysis of PTP1B inhibition by aceriphyllic acid C（1） and aceriphyllic acid D（2） suggested that oleanane-type triterpenes inhibited PTP1B activity in a mixed-type manner.展开更多
基金supported by the Conservation Fund of the State Forestry Administration of China and the Siberian Crane Wetland GEF/UNEP Project(GF/2712-03-4627)
文摘In order to measure the impact of changes in the marsh on breeding Red-crowned Cranes (Grus japonensis) and White-naped Cranes (G.vipio) in the Sanjiang Plain,we conducted a complete crane súrvey in each of the summers of 2007 and 2008,and obtained information on the changes in its marsh through interpretation of satellite images in 1986,1995,2000 and 2005.A comparison between the 1984 and 2008 census shows that:1) the number of Red-crowned Cranes remained stable at about 300 birds,while the number of White-naped Cranes increased markedly; 2) the estimates of nests of Red-crowned cranes are close to the numbers of 1984,while approximately 90％ of the nests of these two crane species were distributed over five national nature reserves (NNRs); 3) the two crane species became more concentrated in three regions,i.e.,the Fuyuan Delta,the middle reaches of the Naoli and Qixing rivers,and the Xingkai Lake wetlands,rather as formerly in six regions.The area of the marsh decreased by 45％ within the 20-year period from 1986 to 2005.The major loss of the marsh area was in the form of a conversion to paddy fields and dry land,which can be primarily attributed to direct human activity under various economic and policy drivers.The disappearance of cranes in the Dulu and Abuqin rivers was induced by large-scale agricultural development.The fragmentation into and isolation of small areas of the marsh became increasingly more serious,which resulted in unsuitable condtions for crane breeding in small patches of the marsh.The number of cranes declined from 1984-1995 but had recovered remarkably by 2008,which may be due to theestablishment of a system of nature reserves,in place since 2000.The land ownership of the reserve plays a key role in maintaining the integrity of the wetland ecosystem,especially in Sanjiang,Honghe,Naolihe and Qixinghe NNRs,which together accommodated approximately 80％ of the population of cranes.However,we did not discover any nests at all in the provincial and municipal reserves,which may be attributed to high human disturbances in these areas.In the end,we propose some recommendations on reserve management.
文摘Egg water was used to induce acrosome reaction in mature sperm of Fenneropenaeus chinensis .Transmission electron microscope and SDS PAGE were used to study the ultrastructure and protein changes of the sperm in F.chinensis ,which has undergone acrosome reaction.The results demonstrated that the sperms from female thelycum could be induced acrosome reaction in vitro by egg water,which was a kind of egg jelly released from oocyte into seawater during oocyte activation.More than fifty percent of sperm finished acrosome reaction during the first 30 min, in vitro .The whole event consists of the retraction of the spike and acrosome exocytosis.Spike was retracted and fused to acrosome cap followed by the release of acrosome granules.When the original egg water was diluted 5 and 10 times,The diluted egg water also have the ability to induce sperm acrosome reaction,but the acrosome reaction rate is much lower than that of the original egg water in the same time.Capillary zone electrophoresis was used to detect the biochemical components of egg water.Egg water was composed of two different components,which were also demonstrated by SDS PAGE.The molecular weights of the two kinds of egg jellies are both about 200kDa.Gelatin substrate SDS PAGE results did not show any hydrolytic enzyme activity in egg water.After acrosome reaction,many sorts of proteins in sperm are degraded.When the reacted sperms were examined with gelatin substrate SDS PAGE,there were six major peptide bands with hydrolytic enzyme activity were detected.Their molecular weights are 200kDa,130 kDa,66 kDa,53 kDa,48 kDa and 41 kDa respectively.These hydrolases cannot be detected in the sperms before acrosome reaction.The acrosome reaction of Chinese shrimp, F.chinensis is much different to that of the sperm in the shrimp, Sicyonia ingentis ,which the acrosome reaction was clearly studied.There is not filament formation during the acrosome reaction in Chinese shrimp.The time of exocytosis in the sperm of Chinese shrimp is also much longer than that of the sperm of Sicyonia ingentis .
基金This study was supported by grants from National Natural Science Foundation of China(No.30240019,30300060)National High Technology Research and Development Program of China(No.2001 AA221I31)+1 种基金Major State Basic Research Project(No.Gl 999055901)State Ministry of Science and Technology Program(No.2002BA7llA0l).
文摘A cDNA, designated as rtSH3p13, was isolated from a rat testis cDNA library. It consists of 1463 bp nuclear acids,which encodes a protein of 312 amino acids and was assigned the GenBank accession number AF227439. The deduced rtSH3p13 protein is a truncated isoform of SH3p13 as a result of mRNA alternative splicing. It is mainly expressed in the rat testis, detected in spermatids at the steps 8-19 of spermiogenesis, and found around the acrosome. During postnatal development, rtSH3p13 appears on day 18 and reaches maximum on day 60. Further experimental results suggested that rtSH3p13 forms a complex with activated epidermal growth factor receptor (EGFR) and interacts with synaptojanin I. Surprisingly, similar to SH3 domain, the V region of rtSH3p13 also inhibits endocytosis in CHO cells.Our results reveal a link between an rtSH3p13-synaptojanin-clathrin complex-mediated formation of pits and the process of spermiogenesis.
文摘Actin filaments (AFs) in un-fixed pollen tubes of Amaryllis vittata Ait were visualized after TRITC-phalloidin staining with DMSO as a permeabilising agent. Typically, strands or hundles of microfilaments (Mfs) were distributed in the extreme tip as well as pollen tubes in a form of network.Fluorescent granules or circles of various sizes were frequently found that continued with the filamentous structures. In addition, a more brightly stained structure, possibly Mf organizing center, was observed. Treatment of pollen tubes with cytochalasin D(CD)for increasing time intervals (5-40 minutes) caused gradual reduction of strands until flurescent granules filled up the pollen tubes. Mcanwhile, cytoplasmie streaming was inhibited completely. Though closely associated with vegetative nuclei (VN) and generative cells (GC), AFs were not found in the cytoplasm of GC.Mg++concentration greatly affected the isolated Mfs.
文摘A membrane protein was isolated from mouse sperm heads that had undergone acrosomal reaction induced by C2+ ionophore, A 23187, which, with a molecular weight of 77.6 kd, shows capability to block egg-sperm fusion. As revealed by analysis usintg isotopic markers, this protein is one of the chief membrane proteins of inner acrosomal membrane or the outer membrane of equatorial segment and Post-acrosomal region; treatment of mouse sperms with 0.6 μg/ml of the Purified protein for 30 minutes reduced the sperm-egg fusion index by 51%.The above results led us to the conclusion that the protein is an active participant in sperm-egg fusion. The possible existence of sperm receptor on egg plasma membrane was discussed.
基金The Scientific Research Foundation for the Returned Overseas Chinese Scholars(Grant No.20091590)State Education Ministry and Key Laboratory of Natural Resources of Changbai Mountain & Functional Molecules(Yanbian University),Ministry of Education,China(Grant No.201003)
文摘An organic layer prepared from the seed of Aceriphyllum rossii was studied to identify the active compounds for protein tyrosine phosphatase 1B（PTP1B） inhibition.Bioassay guided fractionation resulted in the isolation of PTP1B inhibitory activity of triterpenes（1-4）.These four compounds were identified as aceriphyllic acid C（1）,aceriphyllic acid D（2）,aceriphyllic acid E（3） and aceriphyllic acid F（4）.The isolated 1-4 compounds inhibited PTP1B with IC50 values ranged from（2.1±1.5） μmol/L to（11.2±2.5） μmol/L.Kinetic analysis of PTP1B inhibition by aceriphyllic acid C（1） and aceriphyllic acid D（2） suggested that oleanane-type triterpenes inhibited PTP1B activity in a mixed-type manner.
