Tupaia Glis Research Articles

Ultrastructural localization of tyrosine hydroxylase in tree shrew nucleus accumbens core and shell

Many behavioral, physiological, and anatomical studies utilize animal models to investigate human striatal pathologies. Although commonly used, rodent striatum may not present the optimal animal model for certain studies due to a lesser morphological complexity than that of non-human primates, which are increasingly restricted in research. As an alternative, the tree shrew could provide a beneficial animal model for studies of the striatum. The gross morphology of the tree shrew striatum resembles that of primates, with separation of the caudate and putamen by the internal capsule. The neurochemical anatomy of the ventral striatum, specifically the nucleus accumbens, has never been examined. This major region of the limbic system plays a role in normal physiological functioning and is also an area of interest for human striatal disorders. The current study uses immunohistochemistry of calbindin and tyrosine hydroxylase (TH) to determine the ultrastructural organization of the nucleus accumbens core and shell of the tree shrew (Tupaia glis belangeri). Stereology was used to quantify the ultrastructural localization of TH, which displays weaker immunoreactivity in the core and denser immunoreactivity in the shell. In both regions, synapses with TH-immunoreactive axon terminals were primarily symmetric and showed no preference for targeting dendrites versus dendritic spines. The results were compared to previous ultrastructural studies of TH and dopamine in rat and monkey nucleus accumbens. Tree shrews and monkeys show no preference for the postsynaptic target in the shell, in contrast to rats which show a preference for synapsing with dendrites. Tree shrews have a ratio of asymmetric to symmetric synapses formed by TH-immunoreactive terminals that is intermediate between rats and monkeys. The findings from this study support the tree shrew as an alternative model for studies of human striatal pathologies.

Evolutionarily Conserved Pattern of AMPA Receptor Subunit Glycosylation in Mammalian Frontal Cortex

Protein glycosylation may contribute to the evolution of mammalian brain complexity by adapting excitatory neurotransmission in response to environmental and social cues. Balanced excitatory synaptic transmission is primarily mediated by glutamatergic neurotransmission. Previous studies have found that subunits of the AMPA subtype of glutamate receptor are N-glycosylated, which may play a critical role in AMPA receptor trafficking and function at the cell membrane. Studies have predominantly used rodent models to address altered glycosylation in human pathological conditions. Given the rate of mammalian brain evolution and the predicted rate of change in the brain-specific glycoproteome, we asked if there are species-specific changes in glycoprotein expression, focusing on the AMPA receptor. N-glycosylation of AMPA receptor subunits was investigated in rat (Rattus norvegicus), tree shrew (Tupaia glis belangeri), macaque (Macaca nemestrina), and human frontal cortex tissue using a combination of enzymatic deglycosylation and Western blot analysis, as well as lectin binding assays. We found that two AMPA receptor subunits, GluA2 and GluA4, are sensitive to deglycosylation with Endo H and PNGase F. When we enriched for glycosylated proteins using lectin binding assays, we found that all four AMPA receptor subunits are glycosylated, and were predominantly recognized by lectins that bind to glucose or mannose, N-acetylglucosamine (GlcNAc), or 1-6αfucose. We found differences in glycosylation between different subunits, as well as modest differences in glycosylation of homologous subunits between different species.

Island history affects faunal composition: the treeshrews (Mammalia: Scandentia: Tupaiidae) from the Mentawai and Batu Islands, Indonesia

The Mentawai and Batu Island groups off the west coast of Sumatra have a complicated geological and biogeographical history. The Batu Islands have shared a connection with the Sumatran ‘mainland’ during periods of lowered sea level, whereas the Mentawai Islands, despite being a similar distance from Sumatra, have remained isolated from Sumatra, and probably from the Batu Islands as well. These contrasting historical relationships to Sumatra have influenced the compositions of the respective mammalian faunas of these island groups. Treeshrews (Scandentia, Tupaiidae) from these islands have, at various times in their history, been recognized as geographically circumscribed populations of a broadly distributed Tupaia glis, subspecies, or distinct species. We used multivariate analyses of measurements from the skull and hands to compare the island populations from Siberut (Mentawai Islands) and Tanahbala (Batu Islands) with the geographically adjacent species from the southern Mentawai Islands (T. chrysogaster) and Sumatra (T. ferruginea). Results from both the skull and manus of the Siberut population show that it is most similar to T. chrysogaster, whereas the Tanahbala population is more similar to T. ferruginea, confirming predictions based on island history. These results are further corroborated by mammae counts. Based on these lines of evidence, we include the Siberut population in T. chrysogaster and the Tanahbala population in T. ferruginea. Our conclusions expand the known distributions of both the Mentawai and Sumatran species. The larger geographical range of the endangered T. chrysogaster has conservation implications for this Mentawai endemic, so populations and habitat should be re-evaluated on each of the islands it inhabits. However, until such a re-evaluation is conducted, we recommend that the IUCN Red List status of this species be changed from ‘Endangered’ to ‘Data Deficient’. Published 2013. This article is a U.S. Government work and is in the public domain in the USA, Biological Journal of the Linnean Society, 2014, 111, 290–304.

Orbital growth in perinatal primates: a CT and histological study of soft tissue‐bone interfaces

Extant primates are notable for their relatively convergent, or forward‐facing orbits, although some other mammals exhibit similarities, such as a postorbital bar supporting the eye laterally. Here, we use a novel approach of co‐registering micro‐computed tomography (CT) scans of late fetal nonhuman primates with serial histological sections, to infer how orbital morphology emerges during ontogeny. We use three primates (loris, tarsier, tamarin) that have absolutely or allometrically large eyes, and draw a contrast to the tree shrew (Tupaia glis), which may more closely resemble ancestral primate cranial form. Serial slices were annotated to create three‐dimensional cranial reconstructions that reveal the distribution of osteoclasts and osteoblasts. Reconstructions revealed that the superomedial orbit is resorptive in all primate species, although the amount of medial resorption is greatest in the tarsier and tamarin. In contrast, the orbit of Tupaia is depositional except for small inferomedial foci adjacent to infraorbital nerves. Broadly, orbital growth remodeling patterns in primates may be explained by the degree of orbital convergence, which far exceeds that in Tupaia. However, the three primates vary in the degree of orbital convergence and frontation, suggesting that a different factor (e.g., proportional eye size) may influence the similarities in orbital growth patterns.

Using hand proportions to test taxonomic boundaries within theTupaia glisspecies complex (Scandentia, Tupaiidae)

Treeshrews (order Scandentia) comprise 2 families of squirrel-sized terrestrial, arboreal, and scansorial mammals distributed throughout much of tropical South and Southeast Asia. The last comprehensive taxonomic revision of treeshrews was published in 1913, and a well-supported phylogeny clarifying relationships among all currently recognized extant species within the order has only recently been published. Within the family Tupaiidae, 2 widely distributed species, the northern treeshrew, Tupaia belangeri (Wagner, 1841), and the common treeshrew, T. glis (Diard, 1820), represent a particularly vexing taxonomic complex. These 2 species are currently distinguished primarily based on their respective distributions north and south of the Isthmus of Kra on the Malay Peninsula and on their different mammae counts. This problematic species complex includes 54 published synonyms, many of which represent putative island endemics. The widespread T. glis and T. belangeri collectively comprise a monophyletic assemblage representing the sister lineage to a clade composed of the golden-bellied treeshrew, T. chrysogaster Miller, 1903 (Mentawai Islands), and the long-footed treeshrew, T. longipes (Thomas, 1893) (Borneo). As part of a morphological investigation of the T. glis-T. belangeri complex, we studied the proportions of hand bones, which have previously been shown to be useful in discriminating species of soricids (true shrews). We measured 38 variables from digital X-ray images of 148 museum study skins representing several subspecies of T. glis, T. belangeri, T. chrysogaster, and T. longipes and analyzed these data using principal components and cluster analyses. Manus proportions among these 4 species readily distinguish them, particularly in the cases of T. chrysogaster and T. longipes. We then tested the distinctiveness of several of the populations comprising T. glis and T. longipes. T. longipes longipes and T. l. salatana Lyon, 1913, are distinguishable from each other, and populations of T. “glis” from Bangka Island and Sumatra are distinct from those on the Malay Peninsula, supporting the recognition of T. salatana, T. discolor Lyon, 1906, and T. ferruginea Raffles, 1821 as distinct species in Indonesia. These relatively small, potentially vulnerable treeshrew populations occur in the Sundaland biodiversity hotspot and will require additional study to determine their appropriate conservation status.

Morphological distinctiveness of JavanTupaia hypochrysa(Scandentia, Tupaiidae)

The common treeshrew, Tupaia glis, represents a species complex with a complicated taxonomic history. It is distributed mostly south of the Isthmus of Kra on the Malay Peninsula and surrounding islands. In our recent revision of a portion of this species complex, we did not fully assess the population from Java (T. ‘‘glis’’ hypochrysa) because of our limited sample. Herein, we revisit this taxon using multivariate analyses in comparisons with T. glis, T. chrysogaster of the Mentawai Islands, and T. ferruginea from Sumatra. Analyses of both the manus and skull of Javan T. ‘‘glis’’ hypochrysa show it to be most similar to T. chrysogaster and distinct from both T. glis and T. ferruginea. Yet, the Javan population and T. chrysogaster have different mammae counts, supporting recognition of T. hypochrysa as a distinct species. The change in taxonomic status of T. hypochrysa has conservation implications for both T. glis and this Javan endemic.

Molecular profile of Treeshrew, a promising experimental animal for medical research

Scandentia order in Euarchontoglires consists of two families, Tupaiidae and Ptilocercidae , including five genera that contain 20 species. Genus Tupaia having 15 species is the largest genus in the order Scandentia . Most species in Scandentia have a karyotype 2n=52–68, therein, the well-known common treeshrew ( Tupaia glis ) has 2n=60; Northern treeshrew ( Tupaia belangeri chinensis , has 2n=62; pygmy treeshrew ( Tupaia minor ) has 2n=66 and mountain treeshrew ( Tupaia montana ) has 2=68, whereas only one species Mindanao treeshrew ( Urogaleeveretti ) has 2n=44. The whole genome Northern treeshrew ( Tupaia belangeri chinensis ) was sequenced and assembled recently. The size of a 2.86 GB genome was assembled that contains approximately 22 063 protein coding genes very closer to human gene number, and contains 35% of the repeat important element, and 14% of the dominated transposeon in the treeshrew genome. The functional annotation of some important genes and gene families will facilitate treeshrew becoming a promising experimental animal for medicine evaluation alternative to nonhuman primates.

Comparison of the Crown Dimensions between the Maxillary Fourth Deciduous Premolar and the First Molar in Tupaia glis

Comparison of the Crown Dimensions between the Maxillary Fourth Deciduous Premolar and the First Molar in Tupaia glis

Establishment of a molecular tool for blood meal identification in Malaysia

ObjectiveTo establish a polymerase chain reaction (PCR) technique based on cytochrome b (cytb) gene of mitochondria DNA (mtDNA) for blood meal identification. MethodsThe PCR technique was established based on published information and validated using blood sample of laboratory animals of which their whole gene sequences are available in GenBank. PCR was next performed to compile gene sequences of different species of wild rodents. The primers used were complementary to the conserved region of the cytb gene of vertebrate's mtDNA. A total of 100 blood samples, both from laboratory animals and wild rodents were collected and analyzed. The obtained unknown sequences were compared with those in the GenBank database using BLAST program to identify the vertebrate animal species. ResultsGene sequences of 11 species of wild animals caught in 9 localities of Peninsular Malaysia were compiled using the established PCR. The animals involved were Rattus (rattus) tanezumi, Rattus tiomanicus, Leopoldamys sabanus, Tupaia glis, Tupaia minor, Niviventor cremoriventor, Rhinosciurus laticaudatus, Callosciurus caniseps, Sundamys muelleri, Rattus rajah and Maxomys whiteheadi. The BLAST results confirmed the host with exact or nearly exact matches (>89% identity). Ten new gene sequences have been deposited in GenBank database since September 2010. ConclusionsThis study indicates that the PCR direct sequencing system using universal primer sets for vertebrate cytb gene is a promising technique for blood meal identification.

Visual guidance of recovery from lens-induced myopia in tree shrews (Tupaia glis belangeri).

To examine, in tree shrews, the visual guidance of recovery from negative lens-induced myopia by measuring the effect of wearing low-power negative or positive lenses during recovery. To learn if removing a negative lens for 2 h per day, after compensation has occurred, is sufficient to produce recovery. Starting 16 days after natural eye opening (days of visual experience), juvenile tree shrews wore a monocular -5 D lens for 11 days to produce compensation (age-appropriate refraction while wearing the lens). Recovery in four groups was started by discontinuing -5 D lens wear, which caused the treated eyes to be refractively myopic, and substituting: no lens (n = 7), a plano lens (n = 8), a -2 D lens (n = 6) or a +2 D lens (n = 10). In a fifth group (n = 6), the -5 D lens was removed for 2 h each day but worn the remainder of the time. Non-cycloplegic refractive measurements were made daily for the first 10 days and then less frequently. After 31-35 days, the lens-guided recovery period was ended for most animals; periodic measures were continued to assess post-lens recovery changes. All the eyes responded to the -5 D lens and were myopic (-4.8 ± 0.1 D, mean ± S.E.M.) compared to the untreated fellow control eye. In all groups except the -2 D lens group, some animals exhibited slow or incomplete recovery. During recovery, the treated eye of most animals recovered until its refraction, measured with the recovery-lens in place, was near to that of the control eye. Measured without the lens, the -2 D group was myopic and the +2 D group was hyperopic. With the lens in place, the plano-lens, -2 D lens, and +2 D lens groups remained slightly myopic (-1.0 ± 0.3 D, -0.6 ± 0.2 D and -1.3 ± 0.1 D, respectively). The rate of recovery during the first four days was unrelated to the amount of myopia initially experienced by the recovering eyes. Removal of the -5 D lens for 2 h each day produced recovery. During recovery, the emmetropization mechanism uses the presence of myopia, but perhaps not the magnitude, to guide eyes toward a refractive state similar to the control eye, regardless of whether the optically-recovered eye is longer or shorter than the fellow control eye. Wearing a goggle frame containing a lens of any power limits the recovery. The recovery signal can be intermittent, present for only 2 h per day, and still mediate recovery in competition with increasing amounts of hyperopia as recovery progresses.

Comparative effects of ouabain on isolated papillary muscle from tree shrews, guinea-pigs and rats

Inotropic effects of ouabain were investigated in the isolated papillary muscle preparations of the tree shrew (Tupaia glis), guinea-pigs and rats. In the guinea-pig and shrew papillary muscles, ouabain at concentrations of 10(-8) to 3 x 10(-7) M caused a concentration-dependent positive inotropic response in a similar magnitude, while in the rat, ouabain at concentrations of 10(-7) to 3 x 10(-6) M elicited negative inotropic one. Either phentolamine or pindolol in a concentration sufficient to block the alpha- and beta-adrenoceptors did not antagonize the positive inotropic effect of ouabain in the papillary muscle preparation of the shrews.

On the Treeshrew Skull (Mammalia, Placentalia, Scandentia)

Skull anatomy other than the ear region of the pen-tailed treeshrew, Ptilocercus lowii Gray, 1848 (Ptilocercidae), is described and illustrated in detail based on 11 specimens from the Carnegie Museum of Natural History and the United States National Museum. Comparisons are made to the common treeshrew, Tupaia glis (Diard, 1820) (Tupaiidae), in a manner similar to the author's treatment of the ear region (Wible 2009). Included are bone by bone treatment of the external surfaces of the skull and hyoid apparatus, and composite treatment of the endocranium for P. lowii with comparisons to an uncertain species of Tupaia Raffles, 1821, and T. glis. The principal cranial foramina and their contents are addressed.Treeshrews are members of the placental order Scandentia, which is nested within the higher-level clade Euarchonta, along with the order Primates and the order Dermoptera (colugos). Relationships among these three orders are controversial in recent molecular studies, and detailed morphological studies, such as this, provide additional characters for future studies resolving the phylogenetic pattern.

Treeshrews, the primitive primate mammals for medical experimental animals

Treeshrews are small, squirrel-like mammals native to the tropical regions of Southeast Asia, which are placed in Scandentia order including two families, Tupaiidae and Ptilocercidae . There are five genera including 20 species. Genus Tupaia having 15 species is the largest genus in the order. Northern treeshrew ( Tupaia belangeri ) and common treeshrew ( Tupaia glis ) are two of the most famous treeshrews in the Tupaia genus. To date, there has been a great controversy as to whether treeshrews should be placed in the order of insectivore or primates. Treeshrews are generally considered to have a close genetic relationship to primates, and also have some unique characteristics suitable for laboratory animal, such as relatively small body mass, high brain-to-body mass ratio, short reproductive cycle and life span; treeshrews have been proposed to be used as an alternative experimental animal for nonhuman primates. In the past decades, treeshrews as an alternative animal model has been widely applied in biomedical research and safety testing for medicine.

Movements and home range of a common species of tree–shrew, Tupaia glis, surrounding houses of otoacariasis cases in Kuantan, Pahang, Malaysia

Objective To document movement patterns, home range, nesting behaviour and social organization of 5 individuals (3 males and 2 females) of a common species of tree-shrew, Tupaia glis (T. glis) surrounding houses of otoacariasis cases. Methods Each shrew was fitted with a transmitter chip radio-collar which operates between the frequencies of 154.13 MHz to 154.21 MHz. Each transmitter was then tracked with a Portable Telemetry Receiver (Sirtrack, New Zealand) fitted with a 3-element Yagi antenna. Collared shrews were located using standard methods of ground-based triangulation. Each location was taken from at least 2 directional fixes and a minimum of 3 compass bearings. Fixes were taken hourly for each collared individual from the time of emergence from nest (beginning of activity) till time of entry into the nest (end of activity) every day for 5 to 7 continuous days. Three series of radio telemetry observations were carried out. The bearings, time and positions of an observer were recorded and later plotted on a graph paper in order to derive coordinates of the collared animal. [These coordinates then analyzed using Ecological Software Solutions (Biotas Version 1.03)]. Results Nests were found in a jack fruit tree, long bushes, and 2 houses. Daily telemetry detections demonstrated 2 individuals of different sex having nests (or a nest) in the same house. All shrews emerged from and returned to their nests between 0601 to 0659 hours and 1901 to 1959 hours, respectively. Both the time of exit from and entry into nest were the same between sexes ( P>0.05). Their average total active period was 4.90 to 7.00 hours with a total daily travel distant of 270 m to 382 m. A male and a female shrew can move as far as 3 285 m and 4 591 m, respectively. Active movements of T. glis were during daytime. They regularly entered some houses in the area during day and night except for one individual which visited during daytime only. The sizes of home range and core area for the shrews were 2.00–3.40 ha and 0.05–0.42 ha, respectively. Generally, the mean home range size of females was 20.8% larger than that of males. Females covered a 15.4% slightly higher daily movement range compared to males. Conclusions This is the first radio telemetry study in Malaysia to monitor movements and home range of shrews carrying ticks on their body. It demonstrates that shrews are potential carriers of ticks from wild into the houses and their compounds based on their total active periods spent moving around from fruit orchards, secondary forest, plantations and other vegetations to trees in compound of 4 to 7 houses and vice versa. There are also evidences showing shrews have close contact with humans.

Intensity- and focus-dependent modulation of activity (expression of immediate-early gene products) in retinal interneurons of the tree shrew, tupaia glis belangeri6o

Intensity- and focus-dependent modulation of activity (expression of immediate-early gene products) in retinal interneurons of the tree shrew, tupaia glis belangeri6o

The effect of age on compensation for a negative lens and recovery from lens-induced myopia in tree shrews ( Tupaia glis belangeri)

We examined in tree shrews the effect of age on the development of, and recovery from, myopia induced with a negative lens. Starting at 11, 16, 24, 35 or 48 days after natural eye-opening (days of visual experience [VE]), juvenile tree shrews ( n = 5 per group) wore a monocular −5 D lens for 11 days. A long-term lens-wear group ( n = 6) began treatment at 16 days of VE and wore the lens for 30 days. A young adult group ( n = 5) began to wear a −5 D lens between 93 and 107 days of VE (mean ± SD, 100 ± 6 days of VE) and wore the lens for 29–54 days (mean ± SD, 41.8 ± 9.8 days). The recovery phase in all groups was started by discontinuing −5 D lens wear. Contralateral control eyes in the three youngest groups were compared with a group of age-matched normal eyes and showed a small (<1 D), transient myopic shift. The amount of myopia that developed during lens wear was measured as the difference between the treated and control eye refractions. After 11 days of lens wear, the induced myopia was similar for the four younger groups (near full compensation: 11 days, −5.1 ± 0.4 D; 16 days, −4.7 ± 0.3 D; 24 days, −4.9 ± 0.4 D; 35 days, −4.0 ± 0.02) and slightly less in the oldest juvenile group (48 days, −3.3 ± 0.5 D). The young adult animals developed −4.8 ± 0.3 D of myopia after a longer lens-wear period. The rate of compensation (D/day) was high in the 4 youngest groups and decreased in the 48-day and young adult groups. The refractions of the long-term lens-wear juvenile group remained stable after compensating for the −5 D lens. During recovery, all animals in the youngest group recovered fully (<1 D residual myopia) within 7 days. Examples of both rapid (<10 days) and slow recovery (>12 days) occurred in all age groups except the youngest. Every animal showed more rapid recovery (higher recovery slope) in the first 4 days than afterward. One animal showed extremely slow recovery. Based on the time-course of myopia development observed in the youngest age groups, the start of the susceptible period for negative-lens wear is around 11–15 days after eye opening; the rate of compensation remains high until approximately 35 days of VE and then gradually declines. Compensation is stable with continued lens wear. The emmetropization mechanism, both for lens compensation and recovery, remains active into young adulthood. The time-course of recovery is more variable than that of compensation and seems to vary with age, with the amount of myopia (weakly) and with the individual animal.

The Ear Region of the Pen-tailed Treeshrew, Ptilocercus lowii Gray, 1848 (Placentalia, Scandentia, Ptilocercidae)

The ear region of the pen-tailed treeshrew, Ptilocercus lowii Gray, 1848 (Scandentia, Ptilocercidae), is described and illustrated in detail based on five museum specimens from the National Museum of Natural History, two with the auditory bulla removed exposing the intratympanic surfaces. Soft tissues (arteries, veins, nerves, and muscles) are reconstructed onto the adult skulls based on published reports of these elements in a fetal P. lowii. Comparisons are made with four specimens of the common treeshrew, the tupaiid Tupaia glis (Diard, 1820), from the Carnegie Museum of Natural History, including one with the auditory bulla removed.

Networks, trees, and treeshrews: assessing support and identifying conflict with multiple loci and a problematic root.

Multiple unlinked genetic loci often provide a more comprehensive picture of evolutionary history than any single gene can, but analyzing multigene data presents particular challenges. Differing rates and patterns of nucleotide substitution, combined with the limited information available in any data set, can make it difficult to specify a model of evolution. In addition, conflict among loci can be the result of real differences in evolutionary process or of stochastic variance and errors in reconstruction. We used 6 presumably unlinked nuclear loci to investigate relationships within the mammalian family Tupaiidae (Scandentia), containing all but one of the extant tupaiid genera. We used a phylogenetic mixture model to analyze the concatenated data and compared this with results using partitioned models. We found that more complex models were not necessarily preferred under tests using Bayes factors and that model complexity affected both tree length and parameter variance. We also compared the results of single-gene and multigene analyses and used splits networks to analyze the source and degree of conflict among genes. Networks can show specific relationships that are inconsistent with each other; these conflicting and minority relationships, which are implicitly ignored or collapsed by traditional consensus methods, can be useful in identifying the underlying causes of topological uncertainty. In our data, conflict is concentrated around particular relationships, not widespread throughout the tree. This pattern is further clarified by considering conflict surrounding the root separately from conflict within the ingroup. Uncertainty in rooting may be because of the apparent evolutionary distance separating these genera and our outgroup, the tupaiid genus Dendrogale. Unlike a previous mitochondrial study, these nuclear data strongly suggest that the genus Tupaia is not monophyletic with respect to the monotypic Urogale, even when uncertainty about rooting is taken into account. These data concur with mitochondrial DNA on other relationships, including the close affinity of Tupaia tana with the enigmatic Tupaia splendidula and of Tupaia belangeri with Tupaia glis. We also discuss the taxonomic and biogeographic implications of these results.

Species-Specificity in Communication Calls of Tree Shrews (Tupaia: Scandentia)

Tree shrews are small mammals living in the tropical forest of Southeast Asia. The habitus of species within the genus Tupaia is often quite similar, so that it is difficult to differentiate the species based on their morphology. We applied comparative bioacoustics, a tool successfully used to discriminate cryptic species of nocturnal mammals, to investigate whether species in the diurnal genus Tupaia can be recognized noninvasively on the basis of a conspicuous loud call, the chatter. We studied to what extent the chatter call of 2 tree shrew species, Tupaia glis and T. belangeri, differed in acoustic structure. We also acoustically analyzed the chatter call of T. chinensis, a subspecies or closely related parapatric species of T. belangeri. Analyzed acoustic features allowed assigning chatter calls with a probability of more than 73% to the species that produced them. Bioacoustical differences are in line with subtle morphological differences, supporting species status for all 3 studied tree shrew species and corroborating immunodiffusion and genetic data that differentiate T. glis and T. belangeri. Loud calls may offer a reliable noninvasive tool for species diagnosis and discrimination in cryptic species of this diurnal mammalian group.

Molecular cloning and expression characterization of ApoC-I in the orange-spotted grouper

Endogenous yolk nutrients are crucial for embryo and larval development in fish, but developmental behavior of the genes that control yolk utilization remains unknown. Apolipoproteins have been shown to play important roles in lipid transport and uptake through the circulation system. In this study, EcApoC-I, the first cloned ApoC-I in teleosts, has been screened from pituitary cDNA library of female orange-spotted grouper (Epinephelus coioides), and the deduced amino acid sequence shows 43.5% identity to one zebrafish (Danio rerio) hypothetical protein similar to ApoC-I, and 21.2%, 21.7%, 22.5%, 20%, and 22.5% identities to Apo C-I of human (Homo sapiens), house mouse (Mus musculus), common tree shrew (Tupaia glis), dog (Canis lupus familiaris) and hamadryas baboon (Papio hamadryas), respectively. Although the sequence identity is low, amphipathic alpha-helices with the potential to bind to lipid were predicted to exist in the EcApoC-I. RT-PCR analysis revealed that it was first transcribed in gastrula embryos and maintained a relatively stable expression level during the following embryogenesis. During embryonic and early larval development, a very high level of EcApoC-I expression was in the yolk syncytial layer, indicating that it plays a significant role in yolk degradation and transfers nutrition to the embryo and early larva. By the day 7 after hatching, EcApoC-I transcripts were observed in brain. In adult, EcApoC-I mRNA was detected abundantly in brain and gonad. In transitional gonads, the EcApoC-I expression is restricted to the germ cells. The data suggested that EcApoC-I might play an important role in brain and gonad morphogenesis and growth.