Sensitive fluorescence in situ hybridization signal detection in maize using directly labeled probes produced by high concentration DNA polymerase nick translation

The signal produced by fluorescence in situ hybridization (FISH) often is inconsistent among cells and sensitivity is low. Small DNA targets on the chromatin are difficult to detect. We report here an improved nick translation procedure for Texas red and Alexa Fluor 488 direct labeling of FISH probes. Brighter probes can be obtained by adding excess DNA polymerase I. Using such probes, a 30 kb yeast transgene, and the rp1, rp3 and zein multigene clusters were clearly detected.     

Immunolocalization of MMP-19 in the human intervertebral disc: implications for disc aging and degeneration

Matrix metalloproteinases (MMPs) degrade components of the extracellular matrix of the disc, but the presence of MMP-19 has not been explored. In other tissues, MMP-19 is known to act in proteolysis of the insulin-like growth factor (IGF) binding protein-3, thereby exposing this protein to make it available to influence cell behavior. MMP-19 also has been shown to inhibit capillary-like formation and thus play a role in the avascular nature of the disc. Using immunohistochemistry, normal discs from six subjects aged newborn through 10 years and 20 disc specimens from control donors or surgical patients aged 15-76 (mean age 40.2 years) were examined for immunolocalization of MMP-19; six Thompson grade I discs, five Thompson grade II, eight Thompson grade III, five Thompson grade IV, and one Thompson grade V discs were analyzed. The results indicate that in discs from young subjects, MMP-19 was uniformly localized in the outer annulus. In discs from adult donors and surgical patients, outer and inner annulus cells only occasionally showed MMP-19 localization. The greatest expression of MMP-19 was observed in young discs, and little expression was seen in older or degenerating discs. Because MMP-19 has been shown to regulate IGF-mediated proliferation in other tissues, its decline in the aging/degenerating disc may contribute to the age-related decrease in disc cell numbers.     

Searching for a new home: decision making by dispersing brush mice

Natal dispersal occurs when young animals leave the area where they were born and reared and search the surrounding landscape for a new place to settle. Despite the importance of dispersal for both individuals and populations, search behavior by dispersers, including the decision-making process of choosing a place to settle, has not been investigated in the field. Here we draw on the mate search literature, in which the theory of decision making during search has been well developed, and ask whether there are behavioral similarities between habitat search and mate search. We used radiotelemetry to track dispersing juvenile brush mice (Peromyscus boylii) and determined whether their search behavior was consistent with any of three decision rules: threshold, best of n, and comparative Bayes. We found that search behavior by juveniles was most often consistent with comparative decision rules (best of n and comparative Bayes), suggesting that the decision-making processes involved in searching for a place to settle and searching for a mate may be quite similar.     

Functions of fights in territory establishment

Fights are often observed when prospective territory owners settle in patches of vacant habitat, but the function of these fights in space acquisition is obscure. This study tests two hypotheses about the effect of fights on subsequent space use patterns: first, that settlers win space by winning fights and, second, that fights encourage the establishment of mutually exclusive home ranges between opponents (i.e., "fights make neighbors"). The behavior of juvenile Anolts aeneus lizards was recorded as they established territories in patches of habitat in the field. In support of the fights-make-neighbors hypothesis, opponents whose last aggressive interaction was a fight were six times more likely to have mutually exclusive home ranges at the end of the settlement period than were otherwise equivalent dyads whose last encounter was a chase. Contra the hypothesis that settlers win space by winning fights, most last fights ended in a draw, and there was no discernable relationship between the outcome of last fights and the subsequent space use of the contestants. These and previous analyses of settlement behavior in this species suggest that fights during the settlement period encourage the formation of symmetrical social and spatial relationships between neighboring settlers.     

Population dynamics of Monochamus carolinensis (Col., Cerambycidae) under laboratory conditions

The study of life history dynamics of the pine sawyer beetle Monochamus carolinensis (Olivier) is of interest because the beetles are vectors for the pinewood nematode, Bursaphelenchus xylophilus (Steiner and Buhrer) Nickle, the causal agent of pine wilt in susceptible pine trees. Previous observation of a laboratory colony of M. carolinensis suggested numbers of adult beetles reared from logs varied little in relation to oviposition densities among individual logs. Logs in laboratory colonies are routinely subjected to artificially high oviposition rates. The objectives of this study were to examine the relationship between initial oviposition rate, holding time (time between log cut and oviposition), log volume and area and adult survivorship in laboratory colony. This study examined the number of eggs, larvae, adults and generation survivorship in logs over a 2‐year period. The number of adults emerged per log was not related to the number of eggs laid. Late larval and adult numbers were significantly correlated with log size. Only 12% of the initial cohort completed development and emerged as adults. We attribute the high within‐log mortality of beetles to intraspecific competition and cannibalism.     

Parent-offspring conflict that is not limited by degree of kinship

Models are presented showing that, under certain conditions, when multiple offspring are reared simultaneously, the magnitude of offspring selfishness is independent of offspring-offspring genetic relatedness. When the cost (θ) of the selfish offspring's behavior approaches zero, alleles causing offspring selfishness spread as long as $\text{c}\text{b}$ is positive.In general, simultaneous offspring are predicted to behave more selfishly than sequential offspring.Stable equilibria between alleles for selfish and non-selfish behavior are predicted for certain selfish alleles.     

American and korean ginseng tissue cultures: Growth,chemical analysis,and plantlet production

Summary Roots, stems, or leaves of American (Panax quinquefolium) and Korean (Panax ginsing) ginseng were grown as callus or supension tissue cultures. Tissue cultures ofP. ginseng would occasionally form plantlets. The fundamental chemical composition, inorganic analysis, and saponin (panaquilin) content of American and Korean ginseng plants and tissue cultures were determined. The crude saponin content is very similar to, but approximately one-half (1.3%, fresh weight) of that present in ginseng roots. Two-dimensional thin layer chromatographic analysis revealed minor differences in the panaquilins present in American and Korean ginseng tissue cultures. The sapogenin, panaxadiol, was isolated from Korean ginseng callus.     

Ground wētā in vines of the Awatere Valley,Marlborough: biology,density and distribution

The endemic New Zealand ground wētā (Hemiandrus sp. ‘promontorius’) has a Naturally Uncommon conservation status. This is because of the paucity of information on its density and distribution. Here, the biology, density and distribution of a population of this wētā found in and around vineyards in the Awatere Valley, Marlborough was studied. Wētā density was assessed in vineyards, paddocks and shrublands in this valley. Soil moisture, penetration resistance, pH and organic matter were recorded at locations with and without wētā. Wētā density in vineyards was significantly higher than in either paddocks or shrub habitats. In vineyards, the density of this insect was significantly higher under-vines than in the inter-rows. Higher numbers of this wētā were found in moist soils that required lower force to burrow. Females laid an average of 55 eggs between March and April, which hatched in September. These findings highlight the intersection between agriculture and conservation.