大壁虎的染色体及减数分裂联会复合体的研究

大壁虎(Gekko gecko)的染色体数目为2n=38,核型由2对中着丝粒(Nos.1.4.)、3对亚中着丝粒(Nos.2.3.5)及14对端着丝粒和亚端着丝粒(Nos.6—19)染色体组成。一对核仁组织者(NOR_s),位于第7对端着丝粒染色体的末端。同时,本文还对大壁虎的减数分裂以及联会复合体(S.C)的结构和组型,进行了详细的观察和分析。     

Spring and summer microhabitat use by Schlegel’s Japanese gecko,Gekko japonicus (Reptilia: Squamata: Gekkonidae), in urban areas

Differential microhabitat use may be beneficial to achieving fitness in seasonally variable environmental conditions. To explore whether the microhabitat use of the nocturnal Schlegel’s Japanese gecko, Gekko japonicus, varies seasonally and depends on juvenile, male, and female reproductive groups, we investigated five categorical and five quantitative measure variables of microhabitat use in a wild population both in spring and summer. Most geckos were found on white, vertical planes of concrete and plastered brick walls. None of the categorical variables (type of location, substrate, substrate color, light source, and refuge) significantly differed according to season or group, while substrate temperature and irradiance at the location where geckos were observed and the distance from the nearest potential refuge were significantly greater in summer than in spring. The quantitative measure variables did not differ among the reproductive groups. These results suggest that G. japonicus seasonally adjusts its microhabitat use mainly in terms of quantitative measure variables rather than categorical variables.     

Isolation and characterization of microsatellite markers in the gecko Gekko swinhonis and cross‐species amplification in other gekkonid species

Gekko swinhonis is a gekkonid lizard endemic to China, inhabiting Loess Plateau, Huabei Plain, Huanghuai Plain and areas north of the Yangtze River. We characterized 21 dinucleotide microsatellite loci from an AC/AG‐enriched genomic library of G. swinhonis. The number of alleles per locus ranged from eight to 24 and the observed and expected heterozygosities ranged from 0.160 to 0.834 and from 0.584 to 0.917, respectively. We also tested the utility of these loci in other Gekko and Hemidactylus species; many of these loci can be cross‐amplified.     

蛤蚧视觉神经核团的细胞形态结构及功能的研究

本研究发现,蛤蚧视觉神经核团有视顶盖（OT）、峡核（NI）、基底视束核（nBOR）、豆状核（LM）、中脑深部核（NPM）、圆核（NR）、前背侧室嵴（ADVR）和皮质加厚区（Pth）等,其中NI和ADVR两核团的体积最大。视觉核团中有各种形状的细胞形态,其中梨形和梭形细胞占的比例较大。神经核团的细胞直径为6～30μm,其中以15～28μm最多。在ADVR和Pth核团中有细胞丛簇存在,其它核团尚未发现有这样的结构。各神经核团问和核团内有广泛而复杂的纤维联系。蛤蚧有关视觉神经核团除具有视觉功能外,可能还与听觉、触觉、嗅觉和平衡感觉等功能有关。     

Reptilian transferrins: evolution of disulphide bridges and conservation of iron-binding center

Transferrins, found in invertebrates and vertebrates, form a physiologically important family of proteins playing a major role in iron acquisition and transport, defense against microbial pathogens, growth and differentiation. These proteins are bilobal in structure and each lobe is composed of two domains divided by a cleft harboring an iron atom. Vertebrate transferrins comprise of serotransferrins, lactoferrins and ovotransferrins. In mammals serotransferrins transport iron in physiological fluids and deliver it to cells, while lactoferrins scavenge iron, limiting its availability to invading microbes. In oviparous vertebrates there is only one transferrin gene, expressed either in the liver to be delivered to physiological fluids as serotransferrin, or in the oviduct with a final localization in egg white as ovotransferrin. Being products of one gene sero- and ovotransferrin are identical at the amino-acid sequence level but with different, cell specific glycosylation patterns. Our knowledge of the mechanisms of transferrin iron binding and release is based on sequence and structural data obtained for human serotransferrin and hen and duck ovotransferrins. No sequence information about other ovotransferrins was available until our recent publication of turkey, ostrich, and red-eared turtle (TtrF) ovotransferrin mRNA sequences [Ciuraszkiewicz, J., Olczak, M., Watorek, W., 2006. Isolation, cloning and sequencing of transferrins from red-eared turtle, African ostrich and turkey. Comp. Biochem. Physiol. 143 B, 301-310]. In the present paper, ten new reptilian mRNA transferrin sequences obtained from the Nile crocodile (NtrF), bearded dragon (BtrF), Cuban brown anole (AtrF), veiled and Mediterranean chameleons (VtrF and KtrF), sand lizard (StrF), leopard gecko (LtrF), Burmese python (PtrF), African house snake (HtrF), and grass snake (GtrF) are presented and analyzed. Nile crocodile and red-eared turtle transferrins have a disulphide bridge pattern identical to known bird homologues. A partially different disulphide bridge pattern was found in the Squamata (snakes and lizards). The possibility of a unique interdomain disulphide bridge was predicted for LtrF. Differences were found in iron-binding centers from those of previously known transferrins. Substitutions were found in the iron-chelating residues of StrF and TtrF and in the synergistic anion-binding residues of NtrF. In snakes, the transferrin (PtrF, HtrF and GtrF) N-lobe "dilysine trigger" occurring in all other known transferrins was not found, which indicates a different mechanism of iron release.     

Morphological evolution in the day gecko Phelsuma sundbergi in the Seychelles: a multivariate study

Geographic variation was investigated in populations of the day gecko Phelsuma sundbergi from 22 islands in the Seychelles, using multivariate ordination procedures. Multiple group principal components analysis was used to negate ontogenetic variation. Seventy-eight characters from three character systems (body proportions, scalation and colour pattern) were analysed from 349 specimens. Three phenetic aggregations of granitic island populations were detected from the northwestern, northeastern and southern island groups. A comparison of the results from the three character systems analysed separately suggests that the separation of the southern form preceded that of the northern forms. Colour pattern characters reflect this closely, while body proportions and scalation characters follow evolution of body size. The populations of Phelsuma sundbergi on the coralline islands are not well differentiated from the races on the granitic islands, and probably represent recent colonizations or introductions by man.     

A Biomimetic Climbing Robot Based on the Gecko

1 Introduction The locomotion, sensing, navigation, and adapta- tion capabilities in animals have long inspired humans to emulate them in robots. The purpose of this study was to determine the potential of climbing robots for both ter- restrial and extra-terrestrial explorations. Robots similar to their biological counterparts require extensive sys- tems for power, locomotion, and actuation, with com- putation, sensing, and autonomy. From animal research and current technologies, the possibili…     

Isolation and characterization of 12 polymorphic microsatellite markers in the tropical house gecko (Hemidactylus mabouia)

We present 12 variable microsatellite loci isolated from the invasive tropical house gecko, Hemidactylus mabouia. Polymerase chain reaction (PCR) primers were tested on 39 individuals from two locations in Miami, Florida. Heterozygote deficiency was detected for four loci, and we attribute this to possible null alleles or population substructure. Some loci successfully amplified PCR products in several congeners, indicating their potential for use in other geckos.     

Taxonomy and biogeography of Bunopus spatalurus (Reptilia; Gekkonidae) from the Arabian Peninsula

In the last decade, taxonomic studies have drastically increased the number of species known to inhabit the Arabian deserts. While ongoing phylogenetic studies continue to identify new species and high levels of intraspecific genetic diversity, few studies have yet explored the biogeographic patterns in this arid region using an integrative approach. In the present work, we apply different phylogenetic methods to infer relationships within the Palearctic naked‐toed geckos. We specifically address for the first time the taxonomy and biogeography of Bunopus spatalurus Anderson, 1901, from Arabia using multilocus concatenated and species tree phylogenies, haplotype networks and morphology. We also use species distribution modelling and phylogeographic interpolation to explore the phylogeographic structure of Bunopus spatalurus hajarensis in the Hajar Mountains and the roles of climatic stability and possible biogeographic barriers on lineage occurrence and contact zones in this arid mountain endemism hot spot. According to the inferred topology recovered using concatenated and species tree methods, the genus ‘Bunopus’ is polyphyletic. Bunopus tuberculatus and B. blanfordii form a highly supported clade closely related to Crossobamon orientalis, while the two subspecies of ‘Bunopus’ spatalurus branch together as an independent highly supported clade that diverged during the Miocene according to our estimations. Within B. s. hajarensis, three geographically structured clades can be recognized that according to our estimations diverged during the Late Miocene to Pliocene. The paleodistribution models indicate climatic stability during the Late Pleistocene and the lineage occurrence, and predicted contact zones obtained from phylogeographic interpolation therefore probably result from the older splits of the groups when these lineages originated in allopatry. As demonstrated by the results of the multilocus molecular phylogenetic analyses and the topological test carried out in this study, the genus ‘Bunopus’ is not monophyletic. To resolve this, we resurrect the genus Trachydactylus Haas and Battersby, 1959; for the species formerly referred to as Bunopus spatalurus. Considering the morphological differences, the high level of genetic differentiation in the 12S mitochondrial gene and the results of the phylogenetic and the cmos haplotype network analysis, we elevate Trachydactylus spatalurus hajarensis to the species level Trachydactylus hajarensis (Arnold, 1980).