1996 Vol. 17, No. 3
Display Method:
1996, 17(3): 195-202.
The basic characteristics of Coreidae are provided and a detail comparative morphological study about the coreid tribed(or subfamily) is given in the present paper,including the aspects of head,thorax,abdomen,legs,wings,metathoracic scent gland,especially the male and female genitalia and the adjacent structures spermatheca,etc.116 figures are appended.The tribes Acanthocorini,Anisoscelidini,Cloresmini,Colpurinae,Daladerini,Homoeocerini,Petascelidini and the American groups are proved as monophyletic groups respectively,and the tribe Anhomoeini,including only one genus,is proved a good tribe;It is uncertain whether the tribe Coreini is a monophyletic group,or not and the phylogenetic positions of the genera in this tribe need more studies;the genera Sinodasynus,Chinadasynus,Dasynus,Dasynopsis and Paradasynus of the tribe Dasynini are very heterogenetic,Dasynini is a paraphyletic group;the tribe Gonocerini is a monophyletic group,but Plinachtus basalis must be excluded from this tribe;Manocoreini,Mecocnemini and Sinotagini [includes only one species,the another species,Sinotagus rubromaculus Hsiao,must be transferred into genus Anacanthocoris,because of ite characteristics,I.e.,Anacanthocoris rubromaculus (Hsiao)(n.comb.)] includes only one genus respectively,their phylogenetic positions must be studied more;Hydarini(or Hydarinae)is a primitive and peculiar group;tribe Clavigrallini in subfamily Pseudophloeinae is a good tribe,but the systematic positions of the other genera of the subfamily were not certain in the paper,the phylogeny of Pseudophloeinae needs further studies.
1996, 17(3): 203-210.
This paper deals with comparison on morphological characters of the elver (Anguilla japonica Temminck et Schlegel) stock.Samples were collected from seven representative estuaries,Wan Quan He (Hainan),Dong Gang (Taiwan),Han Jiang (Guangdong),Min Jiang (Fujian),Qian Tang Jing (Zhejiang),Chang Jiang (Jiangsu) and Yalu Jiang (Liaoning) Rivers,during the upstream migration periods from 1992 to 1994.According to the 75% rule of Mayrs subspecies identifications,no subspecies had been found among stocks from various estuaries by means of coefficient of difference (CD).The discriminate function analysis of seven meristical and morphometrical characters indicated that there were significant difference (F＞F[0.01]) among stocks from most estuaries in the same years.We believed that these differences might be caused by genetically heterogeneity.Since the change of these differences in various years was unregular,it may be closely related to the random of drift and range of elvers.
1996, 17(3): 211-216.
In this paper fifteen species of the ant genus Pachycondyla F.Smith from China were studied,with 2 new species described,10 new combinations proposed,based on the modern concept of the genus,and 2 species first recorded in China.
1996, 17(3): 217-224.
The present paper aims at describing some aspects on current status,distribution and habitat use of the Chinese water deer (Hydrotes inermis) in Norther Jiangsu Coastal Area.At present,the Chinese water deer distribute from mouth of Biandan River to the Bailin flood gate along the narrow coastal area in Sheyang,Dafeng,Dengtai and Haian County (27-41°N,111-122°E).The population was separated into several small groups.According to the investigation,the population size varied from 850-1523 individuals and is decreasing because of habitat loss.The sex ratio of male to female is 77.3∶100.The ratio of fawn to adult was 1.19∶1.00.Average natality is 1.53 per adult female according to investigation conducted in August.Water deer selected habitat of short grass with patches of tall grass for rest.
1996, 17(3): 225-232.
The forest soil protozoa of Mount Luojia was studied quantitatively with both direct and culture counting methods from January to December in 1993.It was dicovered that the summit of the annual abundance dynamics of protozoa was in spring (March,April & May),the valley in winter (January & Febrary),and the abundance fluntuated gently in summer and fall.The results of regression analyses showed that there were obvious positive correlations between the annual dynamics of protozoan abundance and the variations of water amount and Ph value of the soil,and there was no obvious correlation between the dynamics and the variations of the soil temperature.The dominant species were Bodo edax,Trinema lineare,T.enchelys, B.globosus,Centropyxis elongata,Cryptomonas ovata,Cyclopyxis eurostoma and Cercomonas longicauda.The common species were B.edax,B.globosus,Pleuromonas jaculans,T.lineare,T.enchelys,Centropyxis elongata,Colpoda inflata,C.steinii,Leptopharynx costatus,Frontonia depressa,Cercomonas longycauda,C.cucullus and Monas minimum.The variation trend of protozoan abundance showed by the two counting methods was consistent,but the results of the culture method were 10[2] to 10[3] times as much as the ones of the direct counting method.This demonstrated that most of protozoan individuals existed in cyst forms and only small numbers in active forms in soil,and on the other hand,the culture counting method overestimated the standing crop of soil protozoa.Therefore,we believed that direct counting method gives more reliable estimations of the abundance of soil protozoa and it is better to adopt direct counting method if the objective conditions permit.
1996, 17(3): 233-238.
Twenty four two-month-old virgin Sprague-Dawley rats were used to evaluate the effect of cimaterol (CIM) on growth pattern,biochemical characteristics of selected muscles and hormone level by using a pair design.Rats were alloted by weight to two groups which were ad libitum fed a diet containing 0 or 10 μg/g CIM.The experiment lasted 30 days and rats were weighted every ten days.During the experiment time 10 μg/g CIM improved growth rate and carcass yield,whereas the weight of the subcutaneous waist fat pad was decreased.The results show that CIM can significantly improve growth performance and reduce body fat content in rat.By the end of the study,compared to 0 μg/g,10 μg/g CIM significantly increased the weight and RNA concentration of gastrocnemius (fast-twitch),soleus (slow-twitch) and flexor digitalis pedis superficials (mixed) while decreased DNA concentration.As a result,the ratio of RNA/DNA of the three muscles increased significantly.This implies that the growth of the muscles is through muscle hypertrophy and the fast-twitch muscle is more sensitive to CIM.Dietary CIM also increased pituitary and serum GH content while decreased urea nitrogen level.This suggests that CIM plays its role partially by regulating the endogenous GH secretion in rat.
1996, 17(3): 239-246.
The expression models of the genes in several isozymes in pupae and embryogenesis of tussah,Antheraea pernyi were studied by means of polyacrylamide gel electrophoresis.The results showed the genes of MDH and SOD were expressed in hemolymph,lipid body,oocytes and embryogenesis,while the expression of the genes of LDH and EST appeared only in lipid tissue specificity.The choline esterase did not obviously express during the embryogenesis until larvae.The carboxylesterase,peroxidase and catalase,which dealt with the resistance to the insecticides,were not detected in pupae and embryogenesis.The reuslts of the studies offered an expression model of several isozyme genes in tussah.This also offered a good reference for the study on the resistance of pest insects.
1996, 17(3): 253-258.
Genetic analysis of mammalian free-ranging populations and endangered species utilizing molecular methods,such as protein electrophoresis,DNA RFLP and DNA sequencing,has long been hampered by tissue-sampling problems.We established a non-invasive approach to help to overcome the problems.The genomic DNA of the Asiatic black bear was extracted from single hair shed on the ground using InstaGene Purification Matrix (Bio-rad) with a simple cell lysis step by boiling in the presence of the matrix.Our protocols allow simple,easy and fast DNA preparation by eliminating labor intensive phenol/chloroform extraction.Mitochondrial cytochrome b gene fragment was amplified from hair DNA using PCR technique.Double stranded PCR product was directly sequenced by the dideoxy method using heat denaturation.Our success on determination of mitochondrial cytochrome b gene sequence from hair could be considered as a first step in the population genetic study of the free-ranging Asiatic black bears.
1996, 17(3): 259-262.
In this paper,using protein electrophoresis,we analyzed three species of Apodemus derived from Yunnan Province,A.chevrieri,(8 individuals) A.draco (3 individuals) and A.latronum (1 individual),and 3 individuals of Hapalomys delacouri as outgroup.Products of 27 genetic loci were surveyed,21 of them were found to be polymorphic.We input the data of gene frequences into the PHYLIP program called"Continuous character maximum Likelihood method version 3.5",and got an unrooted tree displaying the genetic relationship among the above species.The unrooted tree indicated that H.delacouri is obviously different from the others consisting a separate group outside,and A.draco also consisted a group repectively while A.latronum was in the A.draco group.According to our results about protein electrophoresis and other studies from morphology and mitochondrial DNA RFLP,we suggested that the A.latronum is closely realated to A.draco while A.chevrieri are genetically different from them to a certain degree.All the three species can be recognized separate species.
1996, 17(3): 263-268.
The mitochondrial DNAs (mtDNAs) from hog-badger (Arctonyx collaris) and siberian weasel (Mustela sibirica) liver were digested with 12 restriciton endonucleases,Apa I,Bgl Ⅰ,Bgl Ⅱ,Cla Ⅰ,EcoR Ⅰ,EcoR V,Hind Ⅲ,Hpa Ⅰ,Pst Ⅰ,Pvu IⅡ,Sca Ⅰ,Sal Ⅰ.The mtDNAs were also cleaved by double-enzyme digestions with the above mentioned enzymes.Restriction maps for hog-badger and siberian weasel were made according to the number and size of those fragments obtained by single and doubledigestions.Combining the previous data,the conservation and variation of mtDNA restriction sites of mammals among far ranged species were also discussed.
1996, 17(3): 269-274.
Fourteen restriction endonucleases,ApaⅠ,AvaⅠ,BamHⅠ,BglⅠ,BglⅡ,DraⅠ,EcoRⅠ,EcoRⅤ,Hind Ⅲ,HpaⅠ,PstⅠ,SalⅠ,ScaⅠ and XhoⅠ,were used to study the mtDNA restriction fragment length polymorphism (RFLP) in 6 individuls of the Hainan and Xuwen yellow cattle from Hainan and Guangdong.Only (SalⅠ) out of 14 restriction enzymes disclosed mtDNA polymorphism within the Hainan yellow cattle,of which the C pattern (15.0,1.3) has not been reported previously.The restriction patterns generated by 13 of the enzymes in Xuwen yellow cattle were identical with those in Hainan yellow cattle.The halotypes of the 6 individuals were almost A-A-A-A-A-A-A alone represented by Bos indicus.Our results showed monophenetic maternal origins of these two breeds of yellow cattle,and suggested that the genetic diversity within the two breeds is remarkably scarce.The low variation and monotoneous population genetic structure indicated a close relationship between the two breeds,which supported the hypothesis that Hainan yellow cattle and Xuwen cattle were from one breed named Leiqiong yellow cattle.
1996, 17(3): 275-286.
The nucleus of dinoflagellates had been used as the model of the primitive nucleus.However,this model was found unsuitable.According to this model the chromosomal basic protein of dinoflagellates should represent a very primitive nucleosomal histone-related protein and the differentiation of four nucleosomal histones should take place after the emergence of the primitive nucleus.But both two deductions were found to be incorrect.In other respect,various studies of molecular evloution studies showed dinoflagellates were not the most primitive ones among present-existing eukaryotes,but might only be the primitive ones among matakaryotes.Superkingdom Archezoa seems to be the primitive eukaryotes,which possess no mitochondria,no typical Golgi apparatus,and no 80S type of ribosomes,but have 70S type of ribosomes just as prokaryotes have.According to the studies of molecular evolution of large rRNAs and 5.8S rRNA,diplomonads,in turn,seem to be the most primitive ones among the present-existing Archezoa,therefore,their nucleus might perhaps be the suitable model of the primitive cell nucleus.Giardia lamblia was used as the representative of diplomonads and the nucleus of its trophozoite was studied in our laboratory in recent years,The following points were found:1.No nucleolus was found with various detection methods.2.The nuclear enevelope of Giardia was found incomplete for the first time.Large openings were seen in its nuclear envelope.The natural existence of the nuclear envelope openings has been confirmed by sequential ultrathin sectiontions.3.Nuclear matrix was already found in its nucleus.4.The nuclear.lamina seems very primitive because only lamin B was found it and it could not bear routine sequential specific extractions for demonstrating nuclear lamina and nuclear matrix.5.The centromere protein B and kinetochore porteins of Giardia were found mostly simlar to the corresponding proteins in various archaebacteria.6.Giardia nucleus was found already having five species of histones.7.Our preliminary observations showed that spindle and spindle microtubules have not been found within the dividing nucleus of Giardia.The possibility that the above described special characteristics were produced only due to the parasitic life of Giardia,was analyzed and refuted.ln literature,nucleolus was never found in several other genera of diplomonads,and in other genera heterochromatin structures were mistaken for nucleolus.According to the electron-microscopical photographs in literatue we found that nuclear envelope openings not only existed in Giardia,but also existed in other diplomonads,whether parasitic or free-living.The discovery of nuclear evelope openings in diplomonads confirmed our hypothesis on the origin of nuclear envelope from the primitvie endoplasmic reticulum in the prokaryotic acestor of eukaryotic cells (Li jing-yan,1979).In the light of the nucleus of diplomonads,we presumed that the primitive nucleus in evloutionary history should have nuclear matrix,nucleosomes,from species of nucleosomal histones and typical eukaryotic chromatin already,but still have no nucleolus and its nuclear envelope should be incomplete.Furthermore,we analyzed the facts concerned and proposed an inference about the archaebacterial ancestor of eukaryotic cells.The whole process of the evloutionary formation of cell nucleus was investigated,especially the formation of eukaryotic chromatin.The significance of the emergence of nuclear matrix in the formation of eukaryotic chromatin was emphasized.At the same time our hypothesis on the origin of nuclear envelope was also further developed.
1996, 17(3): 287-289.
According to the investigations of the nucleus of Giardia in our laboratory and the electron-microscopical photographs of diplomonads and reports in literature,I found that diplomonad nuclei had no nucleolus and that the nuclear envelope was incomplete with large nuclear envelope openings.The ways of their nuclear division ware also all primitive.These primitive characteristics of the nucleus distinguish diplomonads from all other presentknown archezoa.Therefore,I would suggest to divide kingdom Archezoa (Cavalier-Smith,1989) into two kingdoms,Proarchezoa (including diplomonads) and Metarchezoa.Both belong to superkingdom Archezoa (Cavalier-Smith,1989).
1996, 17(3): 290-300.
1996, 17(3): 291-294.
There are evidences showing that diplomonads would be the most primitive eukaryotes among all present-existing organisms.Therefore,the informations about diplomonads nucleus are very important for investigating the origin and early evolution of cell nucleus.However,they are very seldom in literature.The nucleus of Giardia lamblia was investigated as a representative of diplomonad nucleus with electron-microscopy.The perinuclear space within the nuclear envelope of Giardia is very prominent and on this background we found that there were openings on the nuclear envelope,which were very much larger than the nuclear pores.The sixe of the opening varied in different nuclei.At the margin of the opening.the nuclear inner membrane is continuous with the nuclear outer membrane.Therefore,the opening can not be the artefact due to sectioning.Usually,at the opening,there is a nuclear lamina-like thin layer separating nucleoplasm from cytoplasm.The layer seems not membranous,because when Giardia cells were fixed with KMnO[4] to preserve only membranous structures,this layer were absent.The layer might perhaps be a part of the nuclear lamina of Giardia.Although after a series of specific extractions to demonstrate Giardia nuclear matrix;nuclear lamina could not be found (Dai et al.,1996),it might still be exist but only so primitive that could not bear the routine extrations.Nuclear envelope must have originated from the primitive endoplasmic reticulum in the closest prokaryotic ancestor of eukaryotic cells (Li,1979).Those parts of the primitive endoplasmic reticulum,which were directly neighboring to the"nuclear region"of the prokaryotic ancestor evolved into nuclear envelope (Li,1996).According to this hypothesis,at the earlier stage of this evolutionary process,the newly formed primitive nuclear envelope could not enclose the whole nuclear region and there must have remained many openings.The discovery of nuclear envelope openings in Giardia nucleus has confirmed this deduction.
1996, 17(3): 295-299.
Diplomonads seem to be the most primitive archezoa.In literature,almost all the studies on diplomonad nuclear division were accomplished under light microscope,Considerring the primitiveness of diplomonad nucleus,we investigated the nuclear division of cultivated Giardia lamblia with routine electron-microscopy preliminarily.Nuclear envelope was found to be preseved during the whole division process.Spindle or spindle microtubules were never found within dividing nucleus or cytoplasm.No condensed metaphase chromosomes were observed,although heterochromatin could occationally be seen both in dividing nucleus and in interphase nucleus.If there is surely no spinde participating the division process,then colchcine should have no influence on this process.Our experiments showed that various concentrations of colchicine (0.1-20 μg/ml),certainly had no effect on the cell division of Giardia.Immuno-fluorescent microscopical detection was done with anti-tubulin antibody and it was found that no tubulin or tubulin-made structure existed in the interphase nucleus and dividing nucleus,while cytoplasm and flagella gave strong positive reaction.The resuts described above suggested that there is no spindle formed during the nuclear division of Giardia.The possible significance of this phenomenon in the origin and evolution of mitosis was discussed.
1996, 17(3): 301-305.
About how the prokaryotic ancestor molecular of core histones evolved into four kinds of core histones of eukaryote has two possibilities:one is the ancestral molecular had already differentiated into four kinds at stage of prokaryote,the other is this differentiation occurred after the cell evolving into the eukaryotic cell.HMf and HMt,two kinds of histone-related proteins,isolated respectively from Methanothermus fervidus and Methanobacterium thermoautotrophicum △H,Archaebacteria which are most closely related to eukaryote,by reeves laboratory have already differentiated into HMf1,HMf2 and HMt1,HMt2.Up to now,the core histones found from lower eukaryotic cell,such as Leishmania and Tetrahymena,have all differentiated into four kinds.In this paper,the total histones were prepared from Giardia lamblia,the most primitive eukaryotic cell,by engaging in methanol prefixation,two times of 0.3 mol/L HCl extraction,acetone precipitation and DNA affinity chromatography.The results of electrophoresis,SDS gel and acid urea gel,of the Giardia histones showed that seven major protein bands could be resolved,and five of these bands migrated to position similar those of five kinds of calf thymus histones.It seems,therefore,that the Giardia histones have already differentiated and consisted of at least five kinds of histones,and,on certain extent,this supported the hypothesis that the histone had already differentiated into four different kinds at the stage of prokaryotic ancestor of eukaryote.
1996, 17(3): 306-314.
1996, 17(3): 307-313.
When typical dinoflagellate,Crypthecodinium cohnii,was detected with immuno-fluorescent microscopy,its nucleus gave positive reaction to ACA serum against human centromere/kinetochore proteins.However,in its nucleus,just as in nuclei of Tetrahymena and Euglena,spot-like precentromeres have never been found.The immuno-blotting detections with the monoclonal antibody,mACA-2,against human centromere protein,CENP-B,showed that Crypthecodinium and the special dinoflagellate,Oxyrrhis marina,gave the same result which was correspondent with those given by Tetrahymena,Euglena and human Hep-2 cells.With the CENP-B polyclonal antibody,ra-ACA-2,the two dinoflagellates,other protists and Hep-2 cells also gave the results identical to each.These results indicated that CENP-B was highly conservative in eukaryotic evolution.In fact,all the centromere/kinetochore proteins are quite conservative.Therefore,in the immuno-blotting detections done with ACA serum,the positive bands of Tetrahymena and Euglena are quite similar to those of human Hep-2 cells.The bands of the special dinoflagellate,Oxyrrhis,are similar to other protists.although a few bands are absent.However,the bands of typical dinoflagellate are obviously different from Oxyrrhis Sand other eukaryotes.It means that two dinoflagellates are far from each other.The results obtained with the monoclonal antibody,mAb37A5,against the kinetochore proteins of CHO cells,also proposed the above suggestion.In the detections,Tetrahymena gave only a 120 kD band; Euglena and Oxyrrhis gave two bands (45 kD and 120 kD),while Crypthecodinium and archezoan,Giardia,gave three bands (45 kD,50 kD and 120 kD).It is very interesting that various archaebacteria all gave the 45 kD band and the 50 kD band (the third band is of 40 kD)(Wu et al.,1996b).
1996, 17(3): 315-322.
The authors made some improvments of the protein immunoblotting techniques during studies on the centromere proteins in sone protists.The main modifications reported in this paper are as followings.1.Separating gels were modified from a uniform polyacrylamide gel of 12% to linear gradient gels of 5%-12% (or 15%),stacking gel from 5% to 3%,and the separation of protein bands in the gel was much improved.2.Traching dye was changed from bromphenol blue to the pigments in Euglena gracilis SDS-PAGE sample,and the proper electrophoresis stop can be conveniently determined.3.Electrophoretic transfer was changed from 400 Ma,3.5 hurs to 200 mA.17 hurs;the cooling of transfer from air in refrigerator of 4 degree centigrades to flowing water bath,so that the transfer was cooled more successfully.4.The NC memberanes were washed thoroughly with double distilled water,then treated with with 0.1% Triton X-100-TBS after transfer,in order to remove SDS in the protein bands transferred.5.The incubation of antigen-antibody reactions were modified from RT or 37 degree centigrades,1-2 hurs to 4 degree centigrades,thus the backgroung of blotting was much reduced and the specificity of antigen-antibody reactions were much improved.
1996, 17(3): 323-330.
To understand the structure and function of the centromere/kinetochore thoroughly,we need information on its origin and evolution,since every living organization has its own origin and evolutionary history.We analyzed the protein components of the centromere/kinetochore in one archezoa,three archeabacteria and one eubacterium by western blotting with the human centromere protein B (CENP-B) monoclonal antibody,mACA-2,which recognizes the amino end region of human CENP-B; CENP-B polyclonal antibody ra-ACA-2; and mAb37A5,a monoclonal antibody against a peptide of the kinetochore in CHO cells.Giardia lamblia was used as a representative of archezoa,which possess no mitochondria and has 70S prokaryotic ribosomes and therefore is considered the most primitive eukaryotic cell.Three archeabacteria,Halobacterium dachaidenesis sp.nov.F3,Sulfosphaerellus thermoacidophilum S-5,and Thermoplasma acidophilum were used as the representatives of each existing group of archeabacteria—methanogenous-halophilic group,sulfur-dependent thermophilic group and thermoplasma group respectively.E.coli was used the representative of eubacteria.On western blots using the CENP-B monoclonal antibody,mACA-2,Giardia lamblia reacted an 80 kD band that is similar to one of the three bands tound in other protists such as Euglena gracilis and Oxyrris marina (Wu et al.,1996c).Three archeabacteria and E.coli gave negative response to mACA-2 antibody.The CENP-B polyclonal antibody,ra-ACA-2,recognized similar 60 kD and 30 kD bands in Giardia lamblia and the three archeabacteria.The other protists tested also exhibited the two bands,and an additional 50 kD band (Wu et al.,1995a-c).The reference E.coli gave 60 kD band and two bands about 80 kD which were different from those of either archeabacteria or giardia.Western blots of G.lamblias extracts using the kinetochore protein monoclonal antibody,mAb37A5,Giardia lamblia gave 45 kD,50 kD and 120 kD bands,of which the 45 kD and 120 kD bands were also found in other tested protists (Wu et al.,1994).Two archeabacteria,Halobacterium and Sulfosphaerellus,produced 40 kD,45 kD,and 50 kD bands.Another archeabacterium Thermoplasma gave a 35 kD band besides those three.Eubacterium E.coli did not give any positive response.From the results,we can suggest a evolutionary line of mAb37A5 antigen from archeabacteria to protists:Thermoplasma,35 kD,40 kD,45 kD and 50 kD;Halobacterium and Sulfospherellus,40 kD,45 kD and 50 kD;Giardia,45 kD,50 kD and 120 kD;Euglena and Oxyrris,45 kD and 120 kD (Wu et al.,1994).Our results support the hypothesis that the eukaryotic cell evoloved from an ancient archeabacterium,and the nucleus of Giardia is indeed one of the most primitive of the eukaryotic nucleus.Therefore it is in the intermediate position between archeabacteria and eukaryotic cells.Our results suggest that although the centromere/kinetochore is a characteristic structure peculiar to eukaryotic cells,its protein molecular ancestors originated in the archeabacterial ancestor of dukaryotic cells.The differentiation of CENP-Bs N-terminal structure most have occurred after the archeabacterial stage.Acknowledegements:We would like to thank Prof.Dr.Dennis G.Searcy of Univ.of Massachusetts,USA,for giving Thermoplasma acidophilum;Prof.Dr.William C.Earnshaw of Johns Hopkins Univ.School of Medicine,USA,for giving mACA-2 and ra-ACA-2 antibodies;Prof.Dr.Ronald Hancock of Laval Univ.,Canada,for giving mAb37A5 antibody;and Prof.Dr.Laurence D.Etkin of the Department of Molecular Genetics,UTMDACC,USA,for the language.improvement of English manuscript.
Our laboratory and Shanghai Institute of Cell Biology have done a series of works on the cell biology and biochemistry of special dimoflagellate,Oxyrrhis marina for many years.The present work is one amony them.The fine features of the constantly condensed chromosomes of the special dinoflagellate Oxyrrhis marina and the effects of different fixations on the fine featrues were observed and compared with those of the nucleoid of a species of human excrement bacteria,and of the constantly condensed chromosomes of a typical dinoflagellate Prorocentrum micans and a flagellate Euglena sp..Materials were fixed with glutaraldehyde (3%,pH7.0),OsO[4](1.5%,pH7.0),and glutaraldehyde-OsO[4],respectively,The bacteria were also fixed with Ryter and Kellenberger s so-called "standard method".Ultrathin sections were made and stained with uranyl salt routinedly.The fine features of the bacterial nucleoid varied greatly depending upon the fixation methodes used.On the contrary,the features of the condensed chromosomes of Euglena sp.showed no evident changes when different fixation methods were used.As for the condensed chromosomes of typical dinoflagellate,P.micans,both OsO[4] fixation and glutaraldehyde-OsO[4] fixation gave the typical banding features of dinoflagllate chromosomes,while glutaraldehyde fixation resulted in quite different features.Being quite different from the condensed chromosomes of common dinoflagellates,the condensed chromosomes of the special dinoflagellate,Oxyrrhis marina,showed fine features somewhat similar to those of the Euglena chromosomes Different fixation methods did not give evident changes on the fine features of Oxyrrhis chromosomes either.In this respect,O.marina chromosomes were similar to the condensed chromosomes of Euglena and distinct from those of other dinoflagellates.Lots of evidences in cell biology and molecular biology,that have been accumulated,indicated that Oxyrrhis is quite different from other dinoflagellates,but similar and closer to other flagellates.Oxyrrhis chromosomes are not dissolved when DNA:is removed; Oxyrrhis DNA does not contain hydroxymethyl uracil;Oxyrrhis chromatin contains histone-related protein and nucleosome-like particles;its nucleus divides by means of a special endomitosis,which is very different from the dinomitosis of typical dinoflagellates.The present work provides the differece in a new respect.All these facts indicate that Oxyrrhis represents a special group of flagelles which link the common flagellates with dinoflagellates.A new phylum,Phylum Oxyrrhinea,is suggested.This idea tallies with the result of the molecular evolution study of 24S rRNAs of Oxyrrhis and verious dinoflagellates (Lenares et al.,1991).
1996, 17(3): 337-340.
Nuclei of kidney cells of telecost from different genuses,families and orders were used as materials for nuclear transplantation experiments.The somatic cell nuclei (kidney cell) of crucian (Carassius auratus),mud carp (Cirrhinus molitorella) and mouth breeder (Tilapia nilotica) were transplanted into the enucleated egg cytoplasm of carp (Cyprinus carpio).By means of the serial nuclear transplantation,a nucleocytoplasmic hybrid (NCH) embryo developing into blood circulation stage was obtained in intergenus combination (nucleus of crucian and enucleated egg cytoplasm of carp),a NCH embryo of heart beat stage was obtained in interfamily combination (nucleus of mud carp and enucleated egg cytoplasm of carp),and a NCH embryo of muscular contraction stage was obtained in inter-order combination (nucleus of mouth breeder and enucleated egg cytoplasm of carp).Since these nuclei were taken directly from the living somatic cells of several kinds of fish and then transplanted them into the enucleated eggs of other fish,it was unnecessary,for obtaining synchronization of spawing periods between the donor fish and the recipient fish.The results obtained in this experiment indicated that this method might be useful for making nucleocytoplasmic hybrids in telecost.
1996, 17(3): 341-346.
White-cheeked gibbon (H.leucogenys) is distributed in the south of Yunnan,China.The chromosomes of a female and a male were studied by several banding techniques (G-,C- and Ag-staining),and a techniqe for simultaneous exhibiting chromosome replication patterns and late replicating Y chromosome.The diploid chromosome number is 52.There are 22 pairs of metacentrics or submetacentrics (Nos.1-22 );3 pairs of acrocentrics(Nos.23-25),and chromosomes Nos.23-24 with a secondary constriction near the centromere on the short arm.The X chromosome is a large metacentric,and the Y,the smallest acrocentric.Its karyotype formula is 44(M or SM)+6(A),XY(M,A).The centrimeric distribution of heterochromatin has been demonstrated in some chromosomes.In addion,there are 3 kinds of heterochromatin on the chromosomes:(1) absent of centromeric heterochromatin,(2) interstitial heterochromatin,(3) terminal heterochromatin.Interstitial heterochromatin has been observed on the biarm of X chromosome.Y chromosome is completely C-band positive.Silver staining revealed 5 chromosomes with NORs in the male specimen.4 Ag-NORs of them are located on the secondary constriction of chromosomes 23 and 24 respectively,and one of them is located on the Y chromosome which has been confirmed by Fluorescence in situ hybridization (FISH) in the same cell.There are 4 chromosomes with Ag-NORs in the female specimen,and they are also located on the secondary constriction of chromosomes 23 and 24.Moreover,the association of Ag-NORs have been observed.Base on the above results,the relationship in gibbons and the way of chromosome evolution in the genus Hylobates have been discussed.
1996, 17(3): 347-352.
The karyotypes of three species of wood mice have been studied by banding techniques (G-,C- and Ag-staining).Three species have the same diploid number,2n=48.All chromosomes in the complement of A.draco are acrocentrics.The karyotype of A.peninsulae consists of 22 pairs of acrocentrics,1 pair of metacentrics,X and Y are acrocentrics.However,the karyotype of A.latronum consists of 13 pairs of acroentrics,2 pair of subacrocentrics,1 pair of submetacentric,7 pairs of metacentrics,X chromosome is a acrocentric.The G-banded,C-banded and silver-stained karyotypes have been observed.G-banding allows to identify all chromosome pairs in three species.C-banding reveals centromeric heterochromatin in all chromosomes in A.draco.In the C-banded karyotype of A.peninsulae,the centromeric heterochromatin is found in all chromosomes,however,the centromeric C-bands of Nos.7,11,15,21,22 are very fanitly stained even negative,there are also telomeric C-bands in Nos.2,4,7.The Y chromosomes of A.draco and A.peninsulae are whole heterochromatin.The centromeric C-bands of all chromosomes are positive in the C-banded karyotype of A.latronum,but the centromeric C-bands in Nos.3,4,10,12,13 are very fanitly stained.Ag-NORs are predominantly located at Nos.7,8,18,21,22 in A.draco.While Ag-NORs are found in Nos.7,8 in A.peninsulae and A.latronum,respectively.The polymorphism of Ag-NORs of No.22 (in A.draco) and No.7 (in A.peninsulae and A.latronum) is found.Moreover,the classification of three species has also been discussed.
