Natural selection and quantitative genetics of life-history traits in Western women: A twin study

Whether contemporary human populations are still evolving as a result of natural selection has been hotly debated. For natural selection to cause evolutionary change in a trait, variation in the trait must be correlated with fitness and be genetically heritable and there must be no genetic constraints to evolution. These conditions have rarely been tested in human populations. In this study, data from a large twin cohort were used to assess whether selection Will cause a change among women in contemporary Western population for three life-history traits: age at menarche, age at first reproduction, and age at menopause. We control for temporal variation in fecundity (the baby boom phenomenon) and differences between women in educational background and religious affiliation. University-educated women have 35% lower fitness than those with less than seven years education, and Roman Catholic women have about 20% higher fitness than those of other religions. Although these differences were significant, education and religion only accounted for 2% and 1% of variance in fitness, respectively. Using structural equation modeling, we reveal significant genetic influences for all three life-history traits, with heritability estimates of 0.50, 0.23, and 0.45, respectively. However, strong genetic covariation with reproductive fitness could only be demonstrated for age at first reproduction, with much weaker covariation for age at menopause and no significant covariation for age at menarche. Selection may, therefore, lead to the evolution of earlier age at first reproduction in this population. We also estimate substantial heritable variation in fitness itself, with approximately 39% of the variance attributable to additive genetic effects, the remainder consisting of unique environmental effects and small effects from education and religion. We discuss mechanisms that could be maintaining such a high heritability for fitness. Most likely is that selection is now acting on different traits from which it did in pre-industrial human populations.

Characterization of mouse Frizzled-3 expression in hair follicle development and identification of the human homolog in keratinocytes

Frizzled genes encode a family of Wnt ligand receptors, which have a conserved cysteine-rich Wnt binding domain and include both transmembrane and secreted forms. Work by others has shown that experimental perturbation of Wnt signaling results in aberrant hair formation, hair growth, and hair structure. To date, however, there is no information on the contribution of individual Frizzled proteins to hair development. We now report that Frizzled-3 expression in skin is restricted to the epidermis and to the developing hair follicle. Northern analysis on total mouse skin mRNA revealed a single Frizzled-3 transcript of 3.7 kb. Reverse transcription-polymerase chain reaction and in situ hybridization analysis revealed Frizzled-3 expression in epidermal and hair follicle keratinocytes. Frizzled-3 transcripts are first detected in discrete foci in the developing epidermis of 13 d embryos and later in the hair follicle placodes of 15 d embryos, suggesting a role for this Frizzled isoform in follicle development. In 17 d embryos and id old newborn mice Frizzled-3 expression is limited to suprabasal keratinocytes and is not seen in pelage follicles until 3 d postpartum. In 7 d old neonatal skin, Frizzled-3 is expressed throughout the epidermis and in the outer cell layers of hair follicles. We have also identified the mRNA encoding human Frizzled-3 in epidermal keratinocytes and in the HaCaT keratinocyte cell line. Human Frizzled-3 mRNA encodes a 666 amino acid protein with 97.8% identity to the mouse protein. The human Frizzled-3 gene was mapped using a radiation-hybrid cell line panel to the short arm of chromosome 8 between the markers WI-1172 and WI-8496 near the loci for the Hypotrichosis of Marie Unna and Hairless genes.

SOX9 enhances aggrecan gene promoter/enhancer activity and is up-regulated by retinoic acid in a cartilage-derived cell line, TC6

SOX9 is a transcription factor that plays a key role in chondrogenesis, Aggrecan is one of the major structural components in cartilage; however, the molecular mechanism of aggrecan gene regulation has not yet been fully elucidated, TC6 is a clonal chondrocytic cell line derived from articular cartilage, The purpose of this study was to examine whether SOX9 modulates aggrecan gene expression and to further identify molecules that regulate Sox9 expression in TC6 cells. SOX9 overexpression in TC6 cells enhanced by similar to 3-fold the transcriptional activity of the AgCAT-8 construct containing S-kilobase (kb) promoter/first exon/first intron fragments of the aggrecan gene. SOX9 enhancement of aggrecan promoter activity was lost when we deleted a 4.5-kb fragment from the 3'-end of the 8-kb fragment corresponding to the region including the first intron, In TC6 cells, SOX9 enhanced the transcriptional activity of a reporter construct containing the Sry/Sox consensus sequence >10-fold. SOX9 enhancement of aggrecan gene promoter activity and SOX9 transactivation through the Sry/Sox consensus sequence were not observed in osteoblastic osteosarcoma cells (ROS17/2.8), indicating the dependence on the cellular background. Northern blot analysis indicated that TC6 cells constitutively express Sox9 mRNA at relatively low levels. To examine regulation of Sox9 gene expression, we investigated the effects of calciotropic hormones and cytokines, Among these, retinoic acid (RA) specifically enhanced Sox9 mRNA expression in TC6 cells. The basal levels of Sox9 expression and its enhancement by RA were observed similarly at both permissive (33 degrees C) and nonpermissive (39 degrees C) temperatures. Furthermore, RA treatment enhanced the transcriptional activity of a reporter construct containing the Sry/Sox consensus sequence in TC6 cells. Moreover, RA treatment also enhanced the transcriptional activity of another reporter construct containing the enhancer region of the type II procollagen gene in TC6 cells. These observations indicate that SOX9 enhances aggrecan promoter activity and that its expression is up-regulated by RA in TC6 cells.

Yorta Yorta: The effect of changes in traditional laws and customs in native title determinations

Members of the Yorta Yorta Aboriginal Community v State of Victoria was the first case in which a claim for native title was lodged in a non-remote area of the Australian mainland which was the subject of European settlement at an early stage in Australian history - highlights the difficulties in establishing native title claims in long settled regions of Australia - a failure to recognise the strength of oral tradition in establishing Aboriginal connection with the land.

Developmental expression of a class IV POU gene in the gastropod Haliotis asinina supports a conserved role in sensory cell development in bilaterians

POU-IV genes regulate neuronal development in a number of deuterostomes (chordates) and ecdysozoans (arthropods and nematodes). Currently their function and expression in the third bilaterian clade, the Lophotrochozoa, comprising molluscs, annelids and. their affiliates, is unclear. Herein we characterise the developmental expression of HasPOU-IV in the gastropod mollusc, Haliotis asinina. The POU-IV gene is transiently expressed in I I distinct larval territories during the first 3 days of development. HasPOU-IV is first expressed in sets of ventral epidermal cells in the newly hatched trochophore larvae. As larval morphogenesis proceeds, we observe HasPOU-IV transcripts in cells that putatively form a range of sensory systems including chemo- and mechanosensory cells in the foot, cephalic tentacles, the ctenidia. the geosensory statocyst and the eyes. By comparing HasPOU-IV expression with POU-IV genes in other bilaterians we infer that this class of POU-domain genes had an ancestral role in regulating sensory cell development.

Quasimode theory of quantum optical processes in photonic band gap materials

This paper deals with atomic systems coupled to a structured reservoir of quantum EM field modes, with particular relevance to atoms interacting with the field in photonic band gap materials. The case of high Q cavities has been treated elsewhere using Fano diagonalization based on a quasimode approach, showing that the cavity quasimodes are responsible for pseudomodes introduced to treat non-Markovian behaviour. The paper considers a simple model of a photonic band gap case, where the spatially dependent permittivity consists of a constant term plus a small spatially periodic term that leads to a narrow band gap in the spectrum of mode frequencies. Most treatments of photonic band gap materials are based on the true modes, obtained numerically by solving the Helmholtz equation for the actual spatially periodic permittivity. Here the field modes are first treated in terms of a simpler quasimode approach, in which the quasimodes are plane waves associated with the constant permittivity term. Couplings between the quasimodes occur owing to the small periodic term in the permittivity, with selection rules for the coupled modes being related to the reciprocal lattice vectors. This produces a field Hamiltonian in quasimode form. A matrix diagonalization method may be applied to relate true mode annihilation operators to those for quasimodes. The atomic transitions are coupled to all the quasimodes, and the true mode atom-EM field coupling constants (one-photon Rabi frequencies) are related to those for the quasimodes and also expressions are obtained for the true mode density. The results for the one-photon Rabi frequencies differ from those assumed in other work. Expressions for atomic decay rates are obtained using the Fermi Golden rule, although these are valid only well away from the band gaps.

First record of the mite Hirstiella diolii Baker (Prostigmata : Pterygosomatidae) from Australia, with a review of mites found on Australian lizards

We report the First occurrence in Australia of an exotic mite parasite of lizards, Hirstiella diolii Baker (Prostigmata, Pterygosomatidae), and its association with iguanas at the Taronga Zoo in Sydney. We also report on the spread of the exotic snake mite Ophionyssus natricis (Gervais) to native populations of skinks, provide a key to the mites associated with Australian lizards and review how to distinguish chiggers from pterygosomatid mites.

Of mites and bees: A review of mite-bee associations in Australia and a revision of Raymentia Womersley (Acari : Mesostigmata : Laelapidae), with the description of two new species of mites from Lasioglossum (Parasphecodes) spp. (Hymenoptera : Halictidae)

Social bees have a diverse fauna of symbiotic mesostigmatic mites, including highly pathogenic parasites of the honeybee, but there are few reports of Mesostigmata phoretic on or inhabiting the nests of solitary or communal, ground-nesting bees. In south-eastern Australia, however, native bees in the family Halictidae carry what appears to be a substantial radiation of host-specific mesostigmatans in the family Laelapidae. Herein, we redescribe the obscure genus Raymentia , associated with Lasioglossum (Parasphecodes ) spp. bees (Halictidae) and describe two new species, R. eickwortiana from L. lacthium (Smith) and R. walkeriana from L. atronitens (Cockerell). The type species, R. anomala Womersley, is associated with L. altichum (Smith). In addition, we review the mites known to be associated with Australian bees, provide a key to differentiate them, and describe and illustrate acarinaria of the Halictinae. We also report on the first occurrences in Australia of the genera Trochometridium Cross (Heterostigmata: Trochometridiidae), from L. eremaean Walker (Halictidae), and Cheletophyes Oudemans (Prostigmata: Cheyletidae) from Xylocopa Latreille (Xylocopinae), and on the previously unknown association between a Neocypholaelaps Vitzthum (Mesostigmata: Ameroseiidae) and Lipotriches tomentifera (Friese) (Halictidae).

Identity and genetic diversity of the sorghum ergot pathogen in Australia

Sorghum ergot was first discovered in Australia in 1996. It affects seed production and grain usage in stock feed due to concerns of animal toxicity. Three species of Claviceps are known to cause ergot of sorghum with different epidemiological, animal toxicity, and management implications. Claviceps africana was identified as the causal agent but morphological differences between isolates raised the possibility of more than one species being involved. The major aim of this study was to identify the Claviceps species causing sorghum ergot and to determine the genetic diversity among isolates of the ergot pathogen from Australia and overseas. Symptom development, sequencing of the ITS1 region, and radiolabelled DNA amplification fingerprints (RAF) were used to confirm that ergot of sorghum in Australia is caused by C. africana. The morphology of sphacelia, microconidia, macroconidia, and secondary conidia of all 36 Australian isolates studied matched the description for C. africana and the DNA sequence of the ITS1 region of 2 selected Australian isolates was identical to that of C. africana. Based on RAF analysis of 110 Australian and overseas isolates of Claviceps spp., C. africana isolates could be clearly distinguished (

The Mallory body as an aggresome: In vitro studies

Prior in vivo studies supported the concept that Mallory bodies (MBs) are aggresomes of cytokeratins 8 and 18. However, to test this hypothesis an in vitro model is needed to study the dynamics of MB formation. Such a study is difficult because MBs have never been induced in tissue culture. Therefore, MBs were first induced in vivo in drug-primed mice and then primary cultures of hepatocytes from these mice were studied. Two approaches were utilized: 1. Primary cultures were transfected with plasmids containing the sequence for cytokeratin 18 (CK 18) tagged with green fluorescent protein (GFP). 2. Immunofluorescent staining was used to localize the ubiquitin-proteasome pathway components involved in MB-aggresome complex formation in primary hepatocyte cultures. The cells were double stained with a ubiquitin antibody and one of the following antibodies: CK 8, CK 18, tubulin, mutant ubiquitin (UBB+ 1), transglutaminase, phosphothreonine, and the 20S and 26S proteasome subunits P25 and Tbp7, respectively. In the first approach, fluorescence was observed in keratin filaments and MBs 48 h after the cells were transfected with the CK 18 GFP plasmid. Nascent cytokeratin 18 was preferentially concentrated in MBs. Less fluorescence was observed in the normal keratin filaments. This indicated that MBs continued to form in vitro. The immunofluorescent staining of the hepatocytes showed that CK 8 and 18, ubiquitin, mutant ubiquitin (UBB+ 1), P25, Tbp7, phosphothreonine, tubulin, and transglutaminase were all located at the border or the interior of the MB. These results support the concept that MBs are aggresomes of CK 8 and CK 18 and are a result of inhibition of the ubiquitin-proteasome pathway of protein degradation possibly caused by UBB+ 1. (C) 2002 Elsevier Science.

Equine respiratory viruses in foals in New Zealand

AIMS: To identify the respiratory viruses that are present among foals in New Zealand and to establish the age at which foals first become infected with these viruses. METHODS: Foals were recruited to the study in October/ November 1995 at the age of 1 month (Group A) or in March/ April 1996 at the age of 4-6 months (Groups B and C). Nasal swabs and blood samples were collected at monthly intervals. Nasal swabs and peripheral blood leucocytes (PBL) harvested from heparinised blood samples were used for virus isolation; serum harvested from whole-blood samples was used for serological testing for the presence of antibodies against equine herpesvirus (EHV)-1 or -4, equine rhinitis-A virus (ERAV), equine rhinitis-B virus (ERBV), equine adenovirus 1 (EAdV-1), equine arteritis virus (EAV), reovirus 3 and parainfluenza virus type 3 (PIV3). Twelve foals were sampled until December 1996; the remaining 19 foals were lost from the study at various times prior to this date. RESULTS: The only viruses isolated were EHV 2 and EHV 5. EHV 2 was isolated from 155/157 PBL samples collected during the period of study and from 40/172 nasal swabs collected from 18 foals. All isolations from nasal swabs, except one, were made over a period of 2-4 months from January to April (Group A), March to April (Group B) or May, to July (Group C). EHV 5 was isolated from either PBL, nasal swabs, or both, from 15 foals on 32 occasions. All foals were positive for antibodies to EHV 1 or EHV 4, as tested by serum neutralisation (SN), on at least one sampling occasion and all but one were positive for EHV 1 antibodies measured by enzyme-linked immunosorbent assay (ELISA) on at least one sampling occasion. Recent EHV 1 infection was evident at least once during the period of study in 18/23 (78%) foals for which at least two samples were collected. SN antibodies to ERBV were evident in 19/23 (83%) foals on at least one sampling occasion and 15/23 foals showed evidence of seroconversion to ERBV Antibodies to ERAV were only detected in serum samples collected from foals in Group A and probably represented maternally-derived antibodies. Haemagglutination inhibition (HI) antibody titres greater than or equal to 1:10 to EAdV-1 were evident in 21/23 (91%) foals on at least one sampling occasion and 16/23 foals showed serological evidence of recent EAdV-1 infection. None of the 67 serum samples tested were positive for antibodies to EAV, reovirus 3 or PIV3. There was no clear association between infection with any of the viruses isolated or tested for and the presence of overt clinical signs of respiratory disease. CONCLUSIONS: There was serological and/or virological evidence that EHV-1, EHV-2, EHV-5, EAdV-1 and ERBV infections were present among foals in New Zealand. EHV-2 infection was first detected in foals as young as 3 months of age. The isolation of EHV-2 from nasal swabs preceded serological evidence of infection with other respiratory viruses, suggesting that EHV-2 may predispose foals to other viral infections.

Roof gutters: A key container for Aedes aegypti and Ochlerotatus notoscriptus (Diptera : Culicidae) in Australia

The contribution of roof gutters to Aedes aegypti (L.) and Ochlerotatus notoscriptus (Skuse) pupal populations was quantified for the first time in Cairns, Australia. Concurrent yard and roof surveys yielded ill estimated 6,934 mosquito pupae, comprising four species. Roof gutters were all uncommon but productive source of Ae. aegypti in both wet season (n = 11) and dry season (n = 2) surveys, producing 52.6% and 39.5% of the respective populations. First story gutters accounted for 92.3% of the positive gutters. Therefore, treatment of roof gutters is a critical element in Ae. aegypti control campaigns during dengue outbreaks. In wet season yards, the largest standing, crops of Ae. aegypti occurred in garden accoutrements, discarded household items, and rubbish (36.4%, 28.0%, and 20.6%, respectively). In dry season yards, rubbish produced 79.6% of the Ae. aegypti pupae. The number of Ae. aegypti pupae/person was 2.36 and 0.59 for the wet and dry season surveys, respectively.

Plasma growth hormone and growth hormone-binding protein during development in the marsupial brushtail possum (Trichosurus vulpecula)

Plasma concentrations of growth hormone (GH) were measured in the brushtail possum (Trichosurus vulpecula) pouch young from 25 through to 198 days post-partum (n=71). GH concentrations were highest early in pouch life (around 100 ng/ml), and thereafter declined in an exponential fashion to reach adult concentrations (10.8 +/- 1.8 ng/ml; n=21) by approximately 121-145 days post-partum, one to two months before the young is weaned. Growth hormone-binding protein (GHBP), which has been shown to modify the cellular actions of GH in eutherian mammals, was identified for the first time in a marsupial. Based on size exclusion gel filtration, possum GHBP had an estimated molecular mass of approximate to 65 kDa, similar to that identified in other mammalian species, and binding of I-125-labelled human GH (hGH) was displaced by excess hGH (20 mug). An immunoprecipitation method, in which plasma GHBP was rendered polyethylene glycol precipitable with a monoclonal antibody to the rabbit GHBP/GH receptor (MAb 43) and labelled with I-125-hGH, was used to quantitate plasma GHBP by Scatchard analysis in the developing (pooled plasma samples) and adult (individual animals) possums. Binding affinity (K-a) values in pouch young aged between 45 and 54 and 144 and 153 days post-partum varied between 1.0 and 2.4 x 10(9)/M, which was slightly higher than that in adult plasma (0.96 +/- 0.2 x 10(9)/M, n = 6). Binding capacity (B-max) values increased from non-detectable levels in animals aged 25-38 days post-partum to reach concentrations around half that seen in the adult (1.4 +/- 0.2 x 10(-9) M) by about 117 days post-partum and remained at this level until 153 days post-partum. Therefore, in early pouch life when plasma GH concentrations are highest, the very low concentrations of GHBP are unlikely to be important in terms of competing with GH-receptor for ligand or altering the half-life of circulating GH.

Characterization of highly conserved microsatellite loci in Araucaria cunninghamii and related species

Ten microsatellite loci are described in Araucaria cunninghamii, the first reported in the Araucariaceae. Eight were tested in sections Eutacta and Bunya, which diverged more than 200 MYA, and to the sister genus Agathis. Specific amplification products within the expected size range were obtained for six to eight loci in section Eutacta (depending on species), five loci in section Bunya and three. loci in Agathis. Two of the loci (CRCAc1 and CRCAc2, both GA repeats) produced specific amplification products in all taxa, with orthology confirmed by sequence analysis. The repeats were perfect in all taxa. The flanking sequences were extremely conserved, with sequence divergence of 0% to 2.0% within Araucaria species and 2.9% to 7.5% between Araucaria and Agathis. These microsatellites represent some of the most conserved microsatellite loci reported in plants. This may be due to a low evolutionary rate in Araucariaceae genome or the loci may be closely associated with highly conserved, unreported genes.

The role of space as both a conflict trigger and a conflict control mechanism in culturally heterogeneous workgroups

The diversity literature is replete with examples of poor outcomes in Culturally Heterogeneous Workgroups (CHWs) caused by relational difficulties. Although it is widely recognised that culture shapes people's interpretation of behavior and their style of interaction with others in the workplace, what is ill understood is what the specific conflict triggers of these conflicts are. In this paper, we argue that differences in cultural norms and views of physical and psychological space are major triggers of conflict in CHWs. Findings from a field study support the proposition that different viewpoints regarding the use of space, the inability to retreat from exposure to others, decreased interpersonal space, and privacy invasion moderate the relationship between cultural diversity in the workgroup and the type, frequency, and duration of conflict events in CHWs. The paper represents a first step in elucidating the role of space in cross-cultural interactions in the workplace and how space may be a potentially important conflict control mechanism for managers of culturally diverse workgroups.