陇东黄土高原石鸡的分子系统地理结构

本文运用聚合链式反应和直接测序的方法测定陇东黄土高原 8个石鸡 (Alectorischukar)地理种群 78个样本的mtDNA控制区 4 91bp ,建立其分子系统地理结构。 78个样本共发现 2 4个变异位点 ,2 5种单倍型。 8个地理种群共享单倍型C1 ,6个种群共享单倍型C2 ,种群间有一定的基因交流。 8个地理种群的 2 5种单倍型在NJ树中相互混杂 ,没有形成独立的地理结构 ,但聚成两个分支。单倍型网络图显示 2 5种单倍型聚成两个星状的集群 ,分别以单倍型C1和C2为中心。这两个群间的遗传差异显著。陇东黄土高原石鸡的系统地理结构属于“系统发生连续 ,具有部分空间隔离”的地理格局。这种地理格局是更新世冰川、泥石流和人类活动共同作用的结果     

Genetic insight into Mediterranean chukar (Alectoris chukar, Galliformes) populations inferred from mitochondrial DNA and RAPD markers

The chukar (Alectoris chukar, Galliformes) is one of the most important game birds as it is widely distributed and hunted over the whole of its range. The aim of this work was to assess the genetic differentiation as well as the possible presence of hybrid specimens in A. chukar populations from Italy, Greece and Cyprus. To provide phylogenetic context, conspecific, allopatric specimens from Israel, Georgia, Armenia, Kazakhstan, Afghanistan, Pakistan, Mongolia, China and USA were compared. Sequencing of the mitochondrial DNA (mtDNA) Control Region supplied information on the ancestry of A. chukar populations, whereas Random Amplified Polymorphic DNA (RAPD) fingerprinting was used to assess whether hybridization had occurred. The Italian population was found to be an inter-specific mixture of A. chukar and A. rufa (i.e., the red-legged partridge) mtDNA lineages, whereas the representatives from Greece and Cyprus showed only the A. chukar maternal line. RAPD markers revealed introgression with A. rufa genes in the Italian population, whereas no A. chukar × A. rufa hybrid specimens were detected in the eastern Mediterranean populations. The genetic data obtained from the Italian A. chukar population as well as from a few Greek specimens pointed against their Mediterranean kinship, suggesting relationships with A. chukar subspecies from the easternmost part of the Asian continent.     

Introgression of chukar genes into a reintroduced red-legged partridge (Alectoris rufa) population in central Italy

Insight regarding the genetic origin and composition of the studied population of the red-legged partridge (Alectoris rufa) is likely to provide general and critical information for the appropriate management and possible conservation of the species. The reintroduced population of red-legged partridges living in Pianosa Island (National Park Tuscany Archipelago) has proven to be sustainable: captive-bred individuals, morphologically assigned to the taxon A. rufa, were released to the island approximately 20 years ago, establishing an apparently well-adapted population. We have investigated this population by means of 10 microsatellite loci in order to shed light on its genetic structure. Considering that A. rufa is known to crossbreed with A. chukar, the Pianosa Island population was compared at the molecular level with a red-legged partridge breeding stock (Aulla, MS) as well as with a population of pure A. chukar. Our results indicate that the red-legged partridge population from Pianosa, morphologically identified as A. rufa, is actually partly introgressed with A. chukar, questioning its genetic purity and the possible use of this population as a starting stock for future reintroductions elsewhere.     

Functional roles of angiogenic factors and receptors on non‐endothelial cells in the oropharyngeal cavity of the chukar partridge (Alectoris chukar)

The vascular endothelial growth factor (VEGF) family belong to the platelet‐derived growth factor supergene family and is involved in angiogenesis and mitogenesis. The VEGF–VEGFR system regulates endothelial cell proliferation, migration, vascular permeability, secretion and other non‐endothelial cells functions. To clarify the possible role of endothelial and non‐endothelial cells, VEGF and its receptors, vascular endothelial cell growth inhibitor (VEGI) were immunohistochemically examined in oropharyngeal organs. Ten adult partridges were used in this study and the pharynx and larynx were dissected together with the palate and tongue. VEGI, VEGF and its receptor were highly expressed in luminal epithelial and stromal cells, when compared to glandular epithelial and muscle cells (P < 0.05). Moreover, VEGF, its receptors and VEGI were expressed rather strongly in the endothelial cells of the blood capillaries and in both the endothelial and smooth muscle cells of the large and small blood vessels. In conclusion, VEGF and its receptors (flt1/fms, flk1/KDR and flt4) and VEGI were expressed by various cell groups at varying intensity in the oropharyngeal organs. This demonstrates that they play a critical role in the regulation and maintenance of the functions in cells different from endothelial ones as well as in cell proliferation, differentiation, apoptosis and angiogenesis.     

Phylogeography of the rock partridge (Alectoris graeca)

We used mitochondrial DNA control-region and microsatellite data to infer the evolutionary history and past demographic changes in 332 rock partridges (Alectoris graeca) sampled from throughout the species' distribution range, with the exception of the central Balkans region. Maternal and biparental DNA markers indicated concordantly that rock partridge populations are structured geographically (mtDNA phiST = 0.86, microsatellite FST = 0.35; RST = 0.31; P < 0.001). Phylogenetic analyses of 22 mtDNA haplotypes identified two major phylogroups (supported by bootstrap values = 93%), splitting partridges from Sicily vs. all the other sampled populations at an average Tamura-Nei genetic distance of 0.035, which corresponds to 65% of the average distance between closely related species of Alectoris. Coalescent estimates of divergence times suggested that rock partridges in Sicily were isolated for more than 200000 years. This deep subdivision was confirmed by multivariate, Bayesian clustering and population assignment analyses of microsatellite genotypes, which supported also a subdivision of partridges from the Alps vs. populations in the Apennines, Albania and Greece. Partridges in the Apennines and Albania-Greece were probably connected by gene flow since recently through a late Pleistocene Adriatic landbridge. Deglaciated Alps were probably colonized by distinct and, perhaps, not yet sampled source populations. Bottleneck and mismatch analyses indicate that rock partridges have lost variability through past population declines, and did not expand recently. Deglaciated areas could have been recolonized without any strong demographic expansion. Genetic data partially supported subspecies subdivisions, and allowed delimiting distinct conservation units. Rock partridges in Sicily, formally recognized as A. g. whitakeri, met the criteria for a distinct evolutionary significant unit.     

Novel polymorphic microsatellites for the red‐legged partridge (Alectoris rufa) and cross‐species amplification in Alectoris graeca

The red‐legged partridge, Alectoris rufa, is an endemic species of the southwestern Mediterranean, and the most popular game bird in the Iberian Peninsula. A total of 27 microsatellite loci was isolated from an enriched genomic library of A. rufa. Six perfect GT microsatellites were characterized and optimized in 45 individuals of A. rufa. All loci revealed high levels of polymorphism with a number of alleles that ranged from three to 13. Observed heterozygosity ranged from 0.2 to 0.6. Cross‐species amplification showed that all loci were also polymorphic in rock partridge, Alectoris graeca. The new markers will be useful in determining hybridization between both species of Alectoris.     

陇东黄土高原石鸡的遗传多样性与保护

石鸡 (Alectorischukar)是我国北方重要的猎鸟 ,由于栖息地片断化和人类狩猎 ,陇东黄土高原上的石鸡数量正日益减少。本文用PCR直接测序的方法 ,测定了陇东黄土高原 8个石鸡种群mtDNA控制区I区和部分II区的4 91个碱基 ,探讨其遗传多样性。 78个样本共发现 2 4个变异位点 (占所测序列的 4 .89% )和 2 5种单倍型 (占所测样本的 32 .0 5 % )。 8个种群中 ,铜川种群的序列变异率、单倍型多样性和核苷酸多样性都最高 ,分别是 0 .4 7、0 .82和 0 .0 0 2 9;而红回种群的最低 ,仅分别为 0 .10、0 .2 8和 0 .0 0 0 8,这与红回种群受奠基者效应、遗传隔离和自然选择的作用有关。 8个种群共享 1种单倍型C1,说明它们来自共同祖先 ,是 1个单系群 ,属于 1个进化显著单元 ,但它们聚成两个集群。两集群间单倍型相似性指数仅 0 .15 ,遗传距离达 0 .4 3% ,单因素方差分析显示遗传变异差异显著 (F =5 .0 2 >F0 .0 5(14 ,1) =4 .0 6 ) ,分别有 13种和 10种单倍型为两个集群所特有。基于遗传差异性 ,陇东黄土高原的石鸡应分为两个管理单元进行保护 ,尤其对遗传变异和遗传多样性最高的铜川种群应进行重点保护。     

The role of history vs. demography in shaping genetic population structure across an ecotone: chukar partridges (Alectoris chukar) as a case study

Recent advances in molecular ecology allow better assessment of the role of ecological and evolutionary processes in determining the dynamics of genetic diversity in natural populations. The chukar partridge ( Alectoris chukar ) is abundant and continuously distributed in the mesic Mediterranean regions of Israel, becoming scarce and patchily distributed in the arid Negev Desert. This demographic transition occurs across a main environmental transition, the Northern Negev ecotone. Populations of chukars along this gradient have been shown to differ from other populations in morphology, bilateral asymmetry, and in allozyme variation. The aim of this study is to infer whether historical (i.e. secondary contact of formerly vicariant populations) or recurrent demographic events (i.e. restriction to gene flow across the ecotone) have shaped the observed patterns of genetic diversity in chukar populations in Israel. We analysed mtDNA control-region sequences in 216 chukars collected from 28 localities (five distinct geographical regions). Results show that (1) average haplotype diversity is high ( h  = 0.93) while haplotype divergence is low (π= 0.8%), suggesting that extant populations diversified recently; (2) mtDNA gene diversity does not significantly differ across the distribution range; and (3) haplotype distribution differs among the sampling locations ( amova ; P  < 0.00031). Mantel test and autocorrelation analyses indicate that isolation-by-distance may explain the geographical partitioning of genetic diversity. These patterns have likely been produced by complex dynamics between past fragmentation of northern vs. intermediate and southern populations. Late Pleistocene climatic changes, fostering cycles of range contraction and expansion, may have led to genetic differentiation in allopatry, followed by restricted gene flow across secondary contact zones.     

Synchrony, scale and temporal dynamics of rock partridge (Alectoris graeca saxatilis) populations in the Dolomites

1. Harvesting records of rock partridge ( Alectoris graeca saxatilis ) were examined first to identify the presence of cycles in a species with a southern European distribution and then to examine synchrony between populations at a range of scales.
2. Hunting records from 1965 to 1994 were obtained from 210 hunting areas and analysed at three spatial scales: subpopulation, population and metapopulation. Rock partridge exhibited cyclic fluctuations in about 40% of the time series with a period of 4–7 years. The results did not change with spatial scale. The density-dependent structure of the populations showed that most populations exhibited damped oscillations.
3. The proportion of populations that were in synchrony increased with scale from the population to metapopulation level. There was no decline in synchrony with distance but a large variation between populations irrespective of distance.
4. The populations clustered into dry and wet habitats, with those in the dry habitat being more cyclic. We suggest the lack of spatial synchrony with distance but greater synchrony within habitats may reflect the influence of stochastic events operating on populations with different density dependence structures.     

Ultrastructural and histochemical study of the salivary glands of Aplysia depilans (Mollusca, Opisthobranchia)

The digestive system of the sea hare, Aplysia depilans , includes a pair of ribbon-shaped salivary glands. A central duct and a large blood vessel run close to each other along the length of these glands and both are surrounded by a layer of muscle cells. Three cell types form the glandular epithelium: granular cells, vacuolated cells and mucocytes. The granular cells possess cilia and spherical secretion granules, located primarily in the apical region. The granules of immature cells have a low electron density and are mainly formed by neutral polysaccharides with small amounts of proteins. The granules of mature cells are larger, have a high electron density and are mainly formed by proteins with lower amounts of neutral polysaccharides. Transition stages between immature and mature granular cells are observed. The vacuolated cells are large and frequently pyramidal in shape, but after the application of histochemical techniques almost all vacuoles remain uncoloured. The numerous vacuoles contain flocculent material in a clear background and the mitochondria possess large crystalline structures in the matrix. A pyramidal shape is also typical of the mucocytes, which are filled with vesicles containing granular masses surrounded by a network of secretion material. These large cells are strongly stained by Alcian blue, revealing the presence of acidic mucopolysaccharides. This is the first ultrastructural study of the salivary glands in opisthobranch gastropods.     

Primary structure of hemoglobin from gray partridge (Francolinus pondacerianus, Galliformes)

The complete amino acid sequence of the ^A-chain of major hemoglobin component from gray partridgeFrancolinus pondacerianus is presented. The major component HbA accounts for 75% of the total hemolysate. Separation of the globin subunits was achieved by ion-exchange chromatography on CM-Cellulose in 8 M urea. The sequence was studied by automatic Edman degradation of the native chain and its tryptic peptides in a gas-phase sequencer. The phylogenetic relationship of Galliformes with other avian orders is discussed.     

Structural and histochemical changes in the salivary glands of Rhipicephalus appendiculatus during feeding

The salivary glands of the brown ear tick of cattle, R. appendiculatus, from both sexes and at all stages of feeding, were examined as whole glands and as sections for ultrastructural and histochemical changes. The type 1 acinus consists of a basal labyrinth formed by the interdigitations of a central cell and four peripheral cells. These cells form a specialized border with a central constrictor cell which surrounds the acinar duct. The plasma membrane of the central cell is exposed to the duct. The type 1 acini do not appear to secrete active saliva components involved in feeding. The type 2 acini undergo a great increase in synthetic and secretory activity during feeding in both sexes and secrete a lipoprotein probably to form part of the attachment cone and also glycoproteins and esterases of unknown functions. The type 3 acini of both sexes also secrete a lipoprotein probably to form part of the attachment cone. The f cells of these acini in the females transiently secrete a glycoprotein of unknown function and then transform to become part of a water excreting unit. In the males the secretory activity of the granular cells of the type 2 and 3 acini is maintained for further attachments. The type 4 acini of the males accumulate masses of proteinaceous granules. The system of interstitial cells and intercellular spaces in types 2, 3 and 4 acini is large and increasingly active during feeding.     

Histochemical, enzyme histochemical and ultrastructural investigation on the sperm-duct glands of Padogobius martensi (Pisces, Gobiidae)

The functions of the sperm-duct glands of Padogobius martensi were investigated by histochemical, enzyme histochemical and fine structural methods during the prereproductive and reproductive periods, i.e. during their maximum activity. The epithelium lining the spermduct gland tubules produces strongly acidic sulphomucins, probably conjugated with proteins and the variety of sulphomucins increases during the reproductive period when the exocrine epithelium is also involved in the phagocytosis of degenerating sperm cells. A contractile network of myoid cells surround the tubules. The gland interstitium contains cells similar in enzyme histochemical and ultrastructural features to the testicular interstitial cells (Leydig cell homologues). Unlike the latter, however, the interstitial cells of the sperm-duct gland are able to produce steroid glucuronides, which act possibly as pheromones.     

Histology and ultrastructure of the salivary glands in Bulla striata (Mollusca, Opisthobranchia)

Abstract. The ribbon‐shaped salivary glands in Bulla striata were studied with light microscopy and transmission electron microscopy (TEM). Secretion is produced in tubules formed by two types of secretory cells, namely granular mucocytes and vacuolated cells, intercalated with ciliated cells. A central longitudinal duct lined by the same cell types collects the secretion and conducts it to the buccal cavity. In granular mucocytes, the nucleus is usually central and the secretory vesicles contain oval‐shaped granular masses attached to the vesicle membrane. Glycogen granules can be very abundant, filling the space around the secretory vesicles. These cells are strongly stained by PAS reaction for polysaccharides. Their secretory vesicles are also stained by Alcian blue, revealing acidic mucopolysaccharides, and the tetrazonium reaction detects proteins in minute spots at the edge of the vesicles, corresponding to the granular masses observed in TEM. Colloidal iron staining for acidic mucopolysaccharides in TEM reveals iron particles in the electron‐lucent region of the vesicles, while the granular masses are free of particles. In vacuolated cells, which are thinner and less abundant than the granular mucocytes, the nucleus is basal and the cytoplasm contains large electron‐lucent vesicles. These vesicles are very weakly colored by light microscopy techniques, but colloidal iron particles could be observed within them. The golf tee‐shaped ciliated cells contain some electron‐dense lysosomes in the apical region. In these cells, the elongated nucleus is subapically located, and bundles of microfibrils are common in the slender cytoplasmic stalk that reaches the basal lamina. The morphological, histochemical, and cytochemical data showed some similarities between salivary glands in B. striata and Aplysia depilans. These similarities could reflect the phylogenetic relationship between cephalaspidean and anaspidean opisthobranchs or result from a convergent adaptation to an identical herbivorous diet.     

Genetic variability and population structure in Cypriot chukar partridges (Alectoris chukar cypriotes) as determined by microsatellite analysis

For the first time, microsatellite loci were used to study the genetic structure in Alectoris chukar cypriotes. Four of the ten tested microsatellite loci were found to be polymorphic in 33 individuals from four regions of Cyprus. The differentiation test between all the pairs of samples gave non-differentiation exact P values in every case (P>0.05). The posterior probability distribution on the number of source populations indicated only one population (P=0.977); also, a high Bayes factor value (130.020) was obtained. Posterior co-assignment probabilities (measures of similarity) for all pairs of individuals ranged from 0.984 to 1. The global F_IS value was not found to be significant. A recent bottleneck of the Cypriot total partridge population is suggested and this is supported by a significant Wilcoxon test (P=0.031) under the Infinite Alleles Model (IAM) and shifted mode in the alleles frequencies distribution. The results suggest that all the individuals studied belong to only one randomly mating (panmictic) population, with low genetic variation and evidence of recent effective population size reduction (genetic bottleneck). A big hunting pressure exists on the island and about 200,000 captive-bred birds are released every year; these individuals are descendant from a small number of eggs collected in a small area of Cyprus in 1986 and this founder effect could explain the existence of a bottleneck and the low genetic variability.     

A comparative genetic study of two groups of chukar partridges (<Emphasis Type="Italic">Alectoris chukar</Emphasis>) from Cyprus and Argentina,using microsatellite analysis

The aim of the present work is to estimate the usefulness of microsatellite genetic markers analysis to characterize and analyze the possible differences between a captive reared population and a wild one from the same species. The first sample consists of 27 chukar partridges (Alectoris chukar) bred in one farm in Argentina. The second one is composed of 31 chukar partridges coming from a wild Cyprus population (A. chukar cypriotes). We analyzed seven microsatellite loci: MCW135, MCW225, MCW276, MCW280, MCW295, LEI31, and ADL0142. The Argentina group showed higher genetic variation than the Cyprus did. Significant global F _IS value was found in the Argentina sample. Significant genetic differentiation exists between both groups (F _ST=0.394; p<0.01). The Argentina group did not show any signs of bottleneck. Results from Factorial Correspondence Analysis (FCA) suggest that the 58 partridges could be split into two distinct genetic clusters (Cyprus and Argentina). Nevertheless, in the light of PARTITION results, three Argentina individuals might be related to Cyprus. STRUCTURE is unable to assign these three animals to any of the two groups. This could be due to a single or repeated introduction of external individuals into the original Argentina group, so that these results would point to more than one origin for this population. This admixture of individuals could explain the high genetic variation observed in the Argentina farm. Global F _IS value would probably be higher without these immigrations; on the other hand, these admixtures could have prevented bottlenecks.     

Genetic structure of chukar partridge ( Alectoris chukar) populations in the Longdong Loess Plateau, China

This study used polymerase chain reaction (PCR) and dideoxy direct sequencing methods to analyze the genetic structure of the chukar partridge (Alectoris chukar) in the Longdong Loess Plateau, northwestern China. A total of 491 nucleotides of mitochondrial DNA from the control region gene were sequenced for 78 chukar partridges from eight different populations. The 24 variable positions defined 25 haplotypes. The high gene flow (Nm=3.75) implied little genetic differentiation between the eight populations. All the populations shared the haplotype C_1, which suggested that they all came from a common ancestor. The 25 haplotypes were spread through the populations, but could be clustered into two groups. The haplotype similar index between the two groups was only 0.15, with a genetic distance of 0.43%. The genetic variation was significantly different between the two groups, which had been isolated for all of recorded history. The genetic structure of chukar partridge populations in the Plateau appears to be the result of the synergistic effect of a glacier, along with debris flow and human activities since the middle of the Pleistocene.Communicated by F. Bairlein     

Lack of mitochondrial genetic structure in the red‐legged partridge Alectoris rufa (Phasianidae)

A phylogeographic analysis of the control region of mitochondrial DNA was done in 346 individuals of the red‐legged partridge Alectoris rufa (Linnaeus 1758), sampled throughout the species distribution range. The analysis indicated that there is no distinct intraspecific phylogeographical structure, in contrast to earlier studies with lower number of samples. The results are not in accord with the expected distribution of three A. rufa subspecies based on morphological characters (A. r. rufa, A. r. intercedens and A. r. hispanica). The results do not provide statistical support for the five groups (or management units) proposed in some earlier papers because the variation within populations is greater than that found among populations. The absence of a population structure might be a consequence of management activity, consisting of release into the field of individuals bred in farms with no control of their genetic identity and geographic origin. Only the north‐west Iberian populations show a weak population structure, suggesting that A. r. hispanica may have suffered less human influence.     

Human-mediated introgression of exotic chukar (Alectoris chukar, Galliformes) genes from East Asia into native Mediterranean partridges

Mediterranean red-legged (Alectoris rufa) and rock (Alectoris graeca) partridge populations are affected by genetic pollution. The chukar partridge (Alectoris chukar), a species only partly native to Europe, is the most frequently introgressive taxon detected in the genome of hybrid partridges. Both theoretical (evolutionary) and practical (resources management) matters spur to get insight into the geographic origin of the A. chukar hybridizing swarm. The phenotypic A. rufa populations colonizing the easternmost part of the distribution range of this species, the islands of Elba (Italy) and Corsica (France), were investigated. The analysis of both mitochondrial (mtDNA: Cytochrome-b gene plus Control Region: 2,250 characters) and nuclear (Short Tandem Repeats, STR; Random Amplified Polymorphic DNA, RAPD) genomes of 25 wild (Elba) and 20 captive (Corsica) partridges, disclosed spread introgression of chukar origin also in these populations. All mtDNA haplotypes of Elba and Corsica partridges along with those we obtained from other A. rufa (total, n = 111: Italy, Spain, France) and A. graeca (n = 6, Italy), were compared with the mtDNA haplotypes of chukars (n = 205) sampled in 20 countries. It was found that the A. chukar genes detected in red-legged (n = 43) and rock partridges (n = 4) of Spain, France and Italy as well as in either introduced (Italy) or native (Greece, Turkey) chukars (n = 35) were all from East Asia. Hence, a well-defined geographic origin of the exotic chukar genes polluting the genome of native Mediterranean A. rufa and A. graeca (inter-specific level) as well as A. chukar (intra-specific level), was demonstrated.