Social behaviour and social organization of marsupials

Detailed studies of social behaviour and social organization are available at present for relatively few marsupial species, but a considerable body of information is to be found in the literature, and this review attempts to draw it together. The most important avenues of communication appear to be olfactory and auditory, with visual communication relatively unimportant in animals which are predominantly nocturnal. For each family, the different patterns of social organization which occur are discussed in terms of group size, composition and dispersion, mating system, pattern of parental care and nature of social interactions. This information forms the basis of a discussion of how environmental and other factors may have influenced the evolution of social organization. The majority of marsupial species are not group living. Nevertheless, in some species of the families Petauridae, Macropodidae and Phalangeridae, a variety of more or less stable small groups are found, including monogamous pairs and harem groups. Such groups usually have some part of their home range which is exclusive and includes some localized resource. Many of the larger kangaroos of the family Macropodidae are generally seen in groups which may be part of a changing nomadic population or sub-units of a resident population which share a common home range. Minor differences in social organization between species appear to be due mainly to availability and dispersion of food resources. Overall, long-term bonds between males and females are uncommon in marsupials, and the mating system is generally some form of promiscuity. It is argued that the marsupial mode of reproduction and parental care offers no advantage to male or female in long-term bond formation. The female is able to rear young on her own and the male can increase his fitness more by encountering as many females as possible. Hence exclusive home ranges, whether defended or not, are uncommon.     

Hoechst 33258 induced uncondensed sites in marsupial chromosomes

The fluorochrome Hoechst 33258 induces pronounced uncondensed regions at mitosis at one or more specific sites on the X chromosomes of all eighteen species of marsupials belonging to the family Macropodidae which have been examined. The Y chromosomes of nearly all of these species also show sensitive sites. Autosomal regions which respond to this chemical were observed in only five species and there is evidence of polymorphism for two of these. The regions which respond usually show C-banding, but not all C-banding regions are affected. No specific effect was found in the chromosomes of eleven other species examined which are representative of 5 different Australian marsupial families. The implications of the apparent restriction of sex chromosome sensitive sites to macropods are discussed.     

Comparison of habitat selection by two sympatric macropods,Thylogale billardierii and Macropus rufogriseus rufogriseus,in a patchy eucalypt‐forestry environment

Abstract Population density estimates and patterns of habitat selection by sympatric red‐bellied pademelons (Thylogale billardierii (Marsupialia: Macropodidae)) and red‐necked wallabies (Macropus rufogriseus rufogriseus (Marsupialia: Macropodidae)) were examined within a patchy forestry environment in north‐west Tasmania. Population density of both species was relatively high. Selection indices from both population surveys and animal movement data showed that T. billardierii and M. rufogriseus had similar patterns of habitat selection at two spatio‐temporal scales; home range within the study area and habitats selected while foraging at night. Both species selected for young Eucalyptus nitens plantation with high weed‐cover within their home range. At night, T. billardierii and M. rufogriseus selected for open habitats (young plantation and grassland) and avoided closed habitats (native forest and 5–7 years old E. nitens plantation). There was no evidence for resource partitioning between species at these scales. In contrast, the two species differed in their selection for daytime sheltering habitat; T. billardierii selected native forest while M. rufogriseus selected older plantation. This may reflect differences in their predator avoidance strategies; that is, crypsis versus flight, rather than resource partitioning as a result of interspecific competition. The environment appears to be of high quality for both species, with patches of feeding and shelter habitats within close proximity of one another.     

Alpha 1 antitrypsin deficiency: a study of the relationship between the Pi system and genetic markers.

Twenty-four members (4 generations) of a family with alpha 1 antitrypsin deficiency were studied in an attempt to determine the chromosomal location of the Pi system locus. Three alpha 1 antitrypsin alleles (PiM, PiI, and PiZ) and five phenotypes (MM, MZ, MI, IZ, and ZZ) were detected in family members. The quinacrine fluorescent banding technique was successfully utilized to reveal eight polymorphic chromosomal markers in family members. Eight red cell antigens and HL-A antigens were identified for each family member. No linkage between the Pi system and chromosomal markers, four polymorphic red cell antigens, and HL-A antigens was detected. On the basis of this family study, the Pi locus as defined by alpha 1 antitrypsin deficiency does not appear to be on chromosomes 2, 3, 13, 14, 21, or 22 within measurable distance of the markers used.     

Studies on the genetic polymorphism of lactate dehydrogenase B (phenotype B−) in rodent erythrocytes

While the common red cell phenotype of lactate dehydrogenase in mammals includes A and B subunits, in some species, especially of the rodent suborder Myomorpha, LDH B subunits are absent in erythrocytes (phenotype B^–). A polymorphism involving LDH B⁺ and LDH B^– phenotypes was observed in Mus musculus, and it was found that LDH B^– is recessive in relation to LDH B⁺ (Shows and Ruddle, 1968). A similar polymorphism is described here in the field mouse, Apodemus sylvaticus. In family studies, the recessive mode of inheritance is confirmed. Induction of reticulocytosis reveals that the LDH B^– phenotype is not the consequence of degradation of the B subunits in aging red cells. The nature of the mutation giving rise to this polymorphism is discussed.Supported by the Deutsche Forschungsgemeinschaft.     

Comparative transcriptional profiling and evolutionary analysis of the GRAM domain family in eukaryotes

The GRAM domain was found in glucosyltransferases, myotubularins and other membrane-associated proteins. So far, functions for majority of these proteins are yet to be uncovered. In order to address the evolutionary and functional significance of this family members, we have performed a comprehensive investigation on their genome-wide identification, phylogenetic relationship and expression divergence in five different organisms representing monocot/dicot plants, vertebrate/invertebrate animals and yeast, namely, Oryza sativa, Arabidopsis thaliana, Mus musculus, Drosophila melanogaster and Saccharomyces cerevisiae, respectively. We have identified 65 members of GRAM domain family from these organisms. Our data revealed that this family was an ancient group and various organisms had evolved into different family sizes. Large-scale genome duplication and divergence in both expression patterns and functions were significantly contributed to the expansion and retention of this family. Mouse and Drosophila members showed higher divergences in their proteins as indicated by higher Ka/Ks ratios and possessed multiple domains in various combinations. However, in plants, their protein functions were possibly retained with a relatively low divergence as signified by lower Ka/Ks ratios and only one additional domain was combined during evolution. On the other hand, this family in all five organisms exhibited high divergence in their expression patterns both at tissue level and under various biotic and abiotic stresses. These highly divergent expression patterns unraveled the complexity of functions of GRAM domain family. Each member may play specialized roles in a specific tissue or stress condition and may function as regulators of environmental and hormonal signaling.     

云南高背鲫鱼不同组织同工酶分析

采用聚丙烯酰胺凝胶电泳技术,分析了滇池中云南高背鲫鱼(Carassius auratus)的脑、眼睛、肝脏、心脏、肌肉5种组织中的酯酶(EST)、超氧化物歧化酶(SOD)和乳酸脱氢酶(LDH)3种同工酶的表达模式,并对各种酶的同工酶酶谱表型进行了分析。结果表明,云南高背鲫鱼的同工酶系统具有明显的组织特异性,且同工酶的种类与活性变化与其功能相适应。     

Preliminary characterization of the repeated DNA sequence from Vicia sativa

We have identified a family of interspersed repeated sequences present in about 40,000 copies in the genomes of Vicia sativa and its near relative Vicia faba. The element vif is at least 6 kb in length, and members of the repeat family display a degree of heterogeneity in restriction pattern. Homologous elements in V. faba are much more heterogeneous than their V. sativa counterparts; however, analysis of five different V. faba lines revealed substantially the same patterns, suggesting that this family was reamplified prior to the divergence of the lines studied.     

Expression of the gene for mouse lactate dehydrogenase C (Ldhc) is required for male fertility

The lactate dehydrogenase (LDH) protein family members characteristically are distributed in tissue- and cell type-specific patterns and serve as the terminal enzyme of glycolysis, catalyzing reversible oxidation reduction between pyruvate and lactate. They are present as tetramers, and one family member, LDHC, is abundant in spermatocytes, spermatids, and sperm, but also is found in modest amounts in oocytes. We disrupted the Ldhc gene to determine whether LDHC is required for spermatogenesis, oogenesis, and/or sperm and egg function. The targeted disruption of Ldhc severely impaired fertility in male Ldhc(-/-) mice but not in female Ldhc(-/-) mice. Testis and sperm morphology and sperm production appeared to be normal. However, total LDH enzymatic activity was considerably lower in Ldhc(-/-) sperm than in wild type sperm, indicating that the LDHC homotetramer (LDH-C(4)) is responsible for most of the LDH activity in sperm. Although initially motile when isolated, there was a more rapid reduction in the level of ATP and in motility in Ldhc(-)(/-) sperm than in wild-type sperm. Moreover, Ldhc(-/-) sperm did not acquire hyperactivated motility, were unable to penetrate the zona pellucida in vitro, and failed to undergo the phosphorylation events characteristic of capacitation. These studies showed that LDHC plays an essential role in maintenance of the processes of glycolysis and ATP production in the flagellum that are required for male fertility and sperm function.     

Evolution of the rat kallikrein gene family: Gene conversion leads to functional diversity

Summary Kallikrein-like simple serine proteases are encoded by closely related members of a gene family in several mammalian species. Molecular cloning and genomic Southern blot analysis after conventional and pulsed-field gel electrophoresis indicate that the rat kallikrein gene family comprises 15–20 members, probably closely linked at a single locus. Determination of the nucleotide sequences of the rGK-3,-4, and-6 genes here completes sequence data for a total of nine rat kallikrein family members. Comparison of the rat gene sequences to each other and to those of human and mouse kallikrein family genes reveals patterns of relatedness indicative of concerted evolution. Analysis of nucleotide sequence variants in kallikrein family members shows that most sequence variants are shared by multiple family members; the patterns of shared variants are complex and indicate multiple short gene conversions between family members. Sequence exchanges between family members generate novel assortments of variants in amino acid coding regions that may affect substrate specificity and thereby contribute to the diversity of enzyme activity. Furthermore, small sequence exchanges also may play a role in generating the diverse patterns of tissue-specific expression of rat family members. These analyses indicate an important role for gene conversion in the evolution of the functional diversity of these duplicated genes.     

LDH and LDH Isoenzymes of Synovial Fluid in the Horse

LDH is an intracellular enzyme, which when cells degenerate is released to the extracellular spaces and body fluids. Cells and organs in the mammalian body differ from each other with respect to their LDH isoenzyme patterns. These circumstances have led to the use of LDH isoenzyme determinations in laboratory diagnostic work. In the present investigation total LDH activity and LDH isoenzyme distribution in equine synovial fluid from healthy joints, joints with serous arthritis, osteochondrosis dissecans and arthrosis, were determined. The fluids from the diseased joints differed from normal synovial fluid with respect to total LDH activity, and the different joint diseases each seemed to give rise to a characteristic isoenzyme pattern. In order to examine possible sources of the increased LDH activity and altered isoenzyme patterns, blood plasma, red and white blood cells, synovial membrane and articular cartilage were also studied. It was found that LDH4 and LDH5 were present in high amounts in articular cartilage, and an increase in these isoenzymes was the most characteristic feature in synovial fluid from joints with arthrosis. The results were discussed in view of possible diagnostic value of isoenzyme determinations on synovial fluid.     

A mouse cerberus/Dan-related gene family

The Xenopus cerberus gene is able to induce ectopic heads in Xenopus embryos. At the time of its identification, cerberus shared significant homology with only one other protein, the putative rat tumor suppressor protein Dan. Sequence analysis has revealed that cerberus and Dan are members of a family of predicted secreted proteins, here called the can family. The identification of a can-family member in the nematode Caenorhabditis elegans, CeCan1, suggests that this family is of ancient origin. In the mouse, there are at least five family members: Cer1, Drm, PRDC, Dan, and Dte. These genes are expressed in patterns that suggest that they may play important roles in patterning the developing embryo. Cer1 marks the anterior visceral endoderm at E6.5. Dte is expressed asymmetrically in the developing node. Dan is first seen in the head mesoderm of early head fold stage embryos and Drm is expressed in the lateral paraxial mesoderm at E8.5. The region of homology shared by these genes, here called the can domain, closely resembles the cysteine knot motif found in a number of signaling molecules, such as members of the TGFbeta superfamily. Epitope-tagged versions of Cer1 show that, unlike in TGFbeta superfamily members, the cysteine knot motif is not processed away from a proprotein. Recent experiments in Xenopus have suggested that cerberus may act as an inhibitor of BMP signaling. To examine this further, the ability of Dan, Cer1, and human DRM to attenuate Bmp4 signaling has been assessed in P19 cells using pTlx-Lux, a BMP-responsive reporter. All three genes are able to inhibit Bmp4 signaling. These data suggest that the different family members may act to modulate the action of TGFbeta family members during development.     

Analysis of steroid 21-hydroxylase gene in five unrelated Japanese patients with 21-hydroxylase deficiency

DNA samples from five unrelated Japanese patients with 21-hydroxylase (21-OHase) deficiency were studied by Southern analysis using human 21-OHase cDNA. Patterns seen after digestion with not only TaqI but also KpnI showed that two out of the five patients were homozygous for a deletion of the 21-OHase B gene. This result supports the report that the 21-OHase B gene is functional. In the other three, smaller mutations might be responsible for the disorder. The parents of one of the two patients with the deletion had a common ancestor. Hybridization patterns of DNA from members of the family of the patient were consistent with an autosomal recessive mode of inheritance of the deletion that correlates with the clinical phenotype. The deletion segregated with HLA-Aw 24; Bw 61; Cw 3. Heterozygous carriers of 21-OHase deficiency could be detected by comparing the patterns as well as the HLA haplotypes in this family. The application of the family study to the prenatal diagnosis is also discussed.     

Type-A Arabidopsis response regulators are partially redundant negative regulators of cytokinin signaling

Type-A Arabidopsis (Arabidopsis thaliana) response regulators (ARRs) are a family of 10 genes that are rapidly induced by cytokinin and are highly similar to bacterial two-component response regulators. We have isolated T-DNA insertions in six of the type-A ARRs and constructed multiple insertional mutants, including the arr3,4,5,6,8,9 hextuple mutant. Single arr mutants were indistinguishable from the wild type in various cytokinin assays; double and higher order arr mutants showed progressively increasing sensitivity to cytokinin, indicating functional overlap among type-A ARRs and that these genes act as negative regulators of cytokinin responses. The induction of cytokinin primary response genes was amplified in arr mutants, indicating that the primary response to cytokinin is affected. Spatial patterns of ARR gene expression were consistent with partially redundant function of these genes in cytokinin signaling. The arr mutants show altered red light sensitivity, suggesting a general involvement of type-A ARRs in light signal transduction. Further, morphological phenotypes of some arr mutants suggest complex regulatory interactions and gene-specific functions among family members.     

Gene expression patterns of the ALP family during zebrafish development

The actinin-associated LIM protein (ALP) genes belong to the PDZ/LIM protein family which is characterized by the presence of both a PDZ and a LIM domain. The ALP subfamily in mammals has four members: ALP, Elfin, Mystique and RIL. In this study, we have annotated and cloned the zebrafish ALP gene family and identified a zebrafish-specific fifth member of the family, the alp-like gene. We compared the zebrafish sequences to their human and mouse orthologues. A phylogenetic analysis based on the amino acid sequences showed the overall high degree of conservation within the family. We describe here the expression patterns for all five ALP family genes during zebrafish development. Whole mount in situ hybridization results revealed common and distinct expression patterns for the five genes. With the exception of elfin, all genes were expressed as maternal RNAs at early developmental stages. Gene expression for all of them appeared regulated and localized in specific regions at the eight different developmental stages studied. Expression for all five genes was observed in the central nervous system (CNS), which led us to further investigate brain-specific expression in sections of embryos at 2 days of development. In summary, we identified the zebrafish orthologues of the ALP family and determined their gene expression patterns during zebrafish embryogenesis. Finally, we compare our results to the limited expression data available for this gene family during mammalian development.     

Integration of heterologous DNA into the genome of Paracoccus denitrificans is mediated by a family of IS1248-related elements and a second type of integrative recombination event.

All members of the IS1248 family residing in the genome of Paracoccus denitrificans have been isolated by using a set of insertion sequence entrapment vectors. The family consists of five closely related members that integrate the entrapment vectors at distinct sites. One of these, IS1248b, was sequenced and, except for a single base change, shown to be identical to the previously isolated IS1248a. Southern analysis of genomic DNA with labeled IS1248 revealed different hybridization patterns for different isolates of P. denitrificans and Thiosphaera pantotropha. No hybridization was observed with DNA from Thiobacillus versutus and more distantly related species. From a comparison of the fingerprints it was shown that one of the members of the IS1248 family found in P. denitrificans DSM413 is absent in strain NCIB8944, although they are catalogued in international strain catalogues as identical strains. Furthermore, strains Pd1222 and Pd1235, both derivatives of P. denitrificans DSM413, were shown to have different patterns of IS1248 hybridizing restriction fragments. In 14 of 18 strains, the entrapment vectors used in this study were incorporated into the genome via IS1248-mediated cointegrate formation. In the other four strains, the entrapment vectors were shown to be integrated through a different mechanism not involving IS1248.     

The DAP kinase family of pro-apoptotic proteins: novel players in the apoptotic game

The DAP (Death Associated Protein) kinase family is a novel subfamily of pro-apoptotic serine/threonine kinases. All five DAP kinase family members identified to date are ubiquitously expressed in various tissues and are capable of inducing apoptosis. The sequence homology of the five kinases is largely restricted to the N-terminal kinase domain. In contrast, the adjacent C-terminal regions are very diverse and link individual family members to specific signal transduction pathways. There is increasing evidence that DAP kinase family members are involved in both extrinsic and intrinsic pathways of apoptosis and may play a role in tumor progression. This review will focus on structural composition and subcellular localization of DAP kinase family members and on signal transduction pathways leading to their activation. Potential mechanisms of DAP kinase family-mediated apoptosis will be discussed. BioEssays 23:352-358, 2001.     

Lactate dehydrogenase isoenzyme patterns as a method of pregnancy detection in cattle

The objective of this study was to evaluate serum lactate dehydrogenase isoenzyme patterns in open and pregnant Holstein and Hereford cows as a method of detecting pregnancy. Serum samples were collected from 26 Holstein and 13 Hereford cows and lactate dehydrogenase isoenzyme patterns were examined by electrophoresis and quantitated by scanning densitometry. Lactate dehydrogenase isoenzyme(4) and LDH(5) were found in higher concentration (P 相似文献   

Further studies of Dirofilaria roemeri (Nematoda: Filarioidea) in naturally and experimentally infected Macropodidae.

Larval development of D. roemeri occurs in the subcutaneous and intermuscular connective tissue and intramuscularly in the pelvic region and hind limbs of the wallaroo and eastern grey kangaroo. Host response to developing larvae is not evident at 1, 14 and 28 days. The development of D. roemeri in the red kangaroo exhibits features previously observed in both normal and abnormal hosts. Low-level blood microfilaraemia of brief duration occurs in the red kangaroo, which may act as a secondary reservoir of infection for other kangaroo and wallaby species. Among commercially harvested Macropodidae in Queensland there is a greater prevalence of D. roemeri in wallaroos and grey kangaroos than in red kangaroos. Infection is most prevalent in animals from south-central and south-western districts.