The Thick Veins Gene of Drosophila Is Required for Dorsoventral Polarity of the Embryo

We have discovered a new member of the class of genes controlling embryonic dorsoventral patterning. Mutants of the thick veins (tkv) gene have been described previously (as slater alleles) as embryonic lethal, lacking dorsal epidermis, but not as showing a recognizable dorsoventral phenotype. We show here that maternal alteration of function coupled with zygotic reduction of function of tkv is strongly ventralizing. In addition, in double heterozygous combinations in the mother, tkv mutations increase the ventralizing effect of dominant, weakly ventralizing alleles of the maternal effect, dorsoventral genes easter and cactus. An interaction is also seen with zygotic dorsoventral genes: tkv interacts maternally and zygotically in double heterozygotes with decapentaplegic and zygotically with screw in double homozygotes. We conclude that both maternally and zygotically supplied wild-type tkv product can play a role in dorsoventral patterning of the early embryo. On the basis of the phenotype of trans-heterozygous adult escapers, we propose that tkv might act by potentiating the activity of the zygotically acting decapentaplegic gene.     

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.     

Release of the inhibition of messenger RNA translation in extracts of interferon-treated Ehrlich ascites tumor cells by added transfer RNA

In an extract of Ehrlich ascites tumor (EAT) cells which had been “preincubated” for 45 min to lower endogenous protein synthesis (S30_C) the translation of exogenous encephalomyocarditis (EMC) viral mRNA proceeds at a constant rate for over 90 min. In a similarly treated extract of interferon-treated EAT cells (S30_INT) the translation proceeds at a lower rate than in the S30_C for about 30 min and then stops. The impairment of the translation in the S30_INT is mediated by one or more inhibitors. After the cessation of translation the viral mRNA in the S30_INT is in large polysomes. The size of these changes little (if any) during a further 15 min incubation. The addition of mouse tRNA (but not ribosomal RNA or $\text{E. coli}$ tRNA) to the S30_INT after the cessation of viral mRNA translation results in the restart of translation at a rate close to that in the S30_C. This effect of tRNA is diminished by pactamycin, which inhibits peptide chain initiation but not elongation. These results indicate that addition of tRNA allows the elongation of incomplete peptide chains and the initiation of new chains. The need for added tRNA may be due to the fact that in S30_INT the amino acid acceptance of some of the endogenous tRNA species (but not of added tRNAs) is impaired. This impairment is pronounced for leucine and very slight, if any, for five other amino acids tested (i.e. isoleucine, methionine, phenylalanine, threonine, and valine).     

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.     

Haplotyping cryptic Adélie penguin taxa using low-cost,high-resolution melt curves

Distinguishing morphologically cryptic taxa, by definition, requires genetic data such as DNA sequences. However, DNA sequences may not be obtained easily for taxa from remote sites. Here we provide the details of a high-resolution melt-curve-based method using taxon-specific primers that can distinguish two taxa of Adélie penguins, and that will be usable in Antarctica when combined with some of the newly developed field-deployable thermal cyclers. We suggest that the wider adoption of field-deployable polymerase-chain-reaction-based techniques will enable faster assignation of haplotype to individuals in situ, and so allow the targeting of observations and sample collection to specimens relevant to the research question. Targeting individuals will also reduce the need to repeatedly handle animals and reduce the time and travel required to complete field work.