In vitro propagation of Clerodendrum colebrookianum Walp., a potential natural anti-hypertension medicinal plant

A rapid clonal propagation system for Clerodendrum colebrookianum Walp. (Verbenaceae), a anti-hypertension folk medicinal shrub has been developed. A range of cytokinins has been investigated for multiple shoot induction with shoot apex, axillary shoot, leaf, petiole and root explants. Optimum shoot induction occurred with axillary buds using 6-benzyladenine where an average of 21 shoots were produced per explant in 6 weeks. Subculturing the newly produced shoots, by separating into groups of five shoots, produced an average of 43 new shoots per culture within 4 weeks. In vitro rooting and weaning of over 200 plantlets was completely successful. Cytological studies revealed no visible abnormalities in chromosome number.Abbreviations 2iP 2-isopentenyladenine - BA 6-benzyladenine - LSD Least Significant Difference - NAA 1-naphthaleneacetic acid - TDZ thidiazuron - WPM Woody Plant Medium (Lloyd & McCown 1980) basal medium     

Relationship between behavior, adrenal activity, and environment in zoo-housed western lowland gorillas (Gorilla gorilla gorilla)

Monitoring adrenal activity through noninvasive fecal hormone sampling is rapidly gaining popularity as a tool to assess zoo animal welfare. However, few studies have sought to investigate the interrelationships between behavior, adrenal activity, and environment, and ask whether both behavioral and adrenal monitoring strategies are required to assess welfare sufficiently. We present the findings of a 9-month study of a small group (one male, two females) of Western lowland gorillas, Gorilla gorilla gorilla. First, we examined the effect of environmental variables on gorilla behavior. Second, we examined the effect of environmental variables on the concentration of fecal glucocorticoid metabolites (FGC) and the relationship between behavior and FGC. Environmental variables had similar effects on all three gorillas. Negative vigilance of visitors (NVV; staring, posturing, and charging at visitors) significantly increased in all subjects as environmental noise levels increased, and food-related behavior significantly decreased in all subjects as crowd size increased. Exhibit modifications had a number of positive effects on behavior. Notably, when privacy screens were used, NVV significantly decreased in two subjects. We found no significant effects of environmental variables on FGC. However, we did find significant relationships between behavior and FGC in one female. Specifically, her NVV was significantly higher one day before, and on the same day as, raised FGC. Also, hair plucking significantly increased in the two days following raised FGC. Overall, this study demonstrates how concurrent noninvasive fecal and behavioral monitoring can be used for gorilla welfare assessment.     

Maturation Defects in Temperature-sensitive Mutants of Sindbis Virus

Temperature-sensitive mutants of Sindbis virus, which synthesize viral ribonucleic acid (RNA) but not mature virus at the nonpermissible temperature, were selected for the study of viral maturation. Of these, three mutants which complement each other genetically were used. Two major proteins, the nucleocapsid and membrane proteins, located, respectively, in the viral nucleoid and membrane, were found in intact virions. In cells infected with wild-type Sindbis virus, four distinct types of viral RNA with sedimentation coefficients of 40S, 26S, 20S, and 15S were detected in constant distribution. The 20S RNA was ribonuclease-resistant, whereas the other types were ribonuclease-sensitive. The 40S RNA, identical to that obtained from the virion, was found associated with nucleocapsid protein as a subviral particle, which was assumed to be the nucleoid. Viral materials from cells infected with the mutants under nonpermissive conditions were compared with those from cells infected with wild-type virus, in terms of (i) the distribution of the different types of RNA, (ii) the association of infectious viral RNA into subviral particles, and (iii) the ability of infected cells to hemadsorb goose erythrocytes. According to these criteria, each of the three mutants demonstrated different maturation defects. Defective nucleocapsid proteins and membrane proteins may each account for one of the above mutants. The thrid mutant may have defects in a minor structural protein or possibly a maturation protein which is involved in the assembly of Sindbis virus.     

The effects of nuclear DNA content (C-value) on the quality and utility of AFLP fingerprints

BACKGROUND AND AIMS: Nuclear DNA content (C-value) varies approximately 1000-fold across the angiosperms, and this variation has been reported to have an effect on the quality of AFLP fingerprints. Various methods have been proposed for circumventing the problems associated with small and large genomes. Here we investigate the range of nuclear DNA contents across which the standard AFLP protocol can be used. METHODS: AFLP fingerprinting was conducted on an automated platform using the standard protocol (with 3 + 3 selective bases) in which DNA fragments are visualized as bands. Species with nuclear DNA contents ranging from 1C = 0.2 to 32.35 pg were included, and the total number of bands and the number of polymorphic bands were counted. For the species with the smallest C-value (Bixa orellana) and for one of the species with a large C-value (Damasonium alisma), alternative protocols using 2 + 3 and 3 + 4 selective bases, respectively, were also used. KEY RESULTS: Acceptable AFLP traces were obtained using the standard protocol with 1C-values of 0.30-8.43 pg. Below this range, the quality was improved by using 2 + 3 selective bases. Above this range, the traces were generally characterized by a few strongly amplifying bands and noisy baselines. Damasonium alisma, however, gave more even traces, probably due to it being a tetraploid. CONCLUSIONS: We propose that for known polyploids, genome size is a more useful indicator than the 1C-value in deciding which AFLP protocol to use. Thus, knowledge of ploidy (allowing estimation of genome size) and C-value are both important. For small genomes, the number of interpretable bands can be increased by decreasing the number of selective bases. For larger genomes, increasing the number of bases does not necessarily decrease the number of bands as predicted. The presence of a small number of strongly amplifying bands is likely to be linked to the presence of repetitive DNA sequences in high copy number in taxa with large genomes.     

Sharpening of directional responses along the auditory pathway of the oyster toadfish, <Emphasis Type="Italic">Opsanus tau</Emphasis>

Our previous studies have shown that the peripheral auditory system of the toadfish encodes the direction of a sound source. Here, we compare directional responses of peripheral saccular afferents, cells in the descending octaval nucleus (DON) of the medulla, and the torus semicircularis (TS) of the midbrain. Recording locations in the brain were labeled with neurobiotin to confirm the site. To compare directional responses among cells, we calculated an index [sharpening ratio (SR)] that weights the relative strength of responses to the best direction for that cell and to the adjacent stimulus angles tested. Unsharpened saccular afferents tend to have a cosinusoidal directional response pattern (DRP) with an expected SR of 0.87. In DON, more than 60% of the cells exhibited directional sharpening (defined as SR <0.8). In TS, more than 80% of the cells exhibited directional sharpening. We conclude that directional auditory sharpening first occurs in DON and some additional sharpening occurs in the ascending pathway to the midbrain, particularly in azimuth. The sharpening of directional selectivity is likely to be an important component of the neural computations underlying directional hearing.     

Evidence for domesticated and wild populations of Saccharomyces cerevisiae

Saccharomyces cerevisiae is predominantly found in association with human activities, particularly the production of alcoholic beverages. S. paradoxus, the closest known relative of S. cerevisiae, is commonly found on exudates and bark of deciduous trees and in associated soils. This has lead to the idea that S. cerevisiae is a domesticated species, specialized for the fermentation of alcoholic beverages, and isolates of S. cerevisiae from other sources simply represent migrants from these fermentations. We have surveyed DNA sequence diversity at five loci in 81 strains of S. cerevisiae that were isolated from a variety of human and natural fermentations as well as sources unrelated to alcoholic beverage production, such as tree exudates and immunocompromised patients. Diversity within vineyard strains and within saké strains is low, consistent with their status as domesticated stocks. The oldest lineages and the majority of variation are found in strains from sources unrelated to wine production. We propose a model whereby two specialized breeds of S. cerevisiae have been created, one for the production of grape wine and one for the production of saké wine. We estimate that these two breeds have remained isolated from one another for thousands of years, consistent with the earliest archeological evidence for wine-making. We conclude that although there are clearly strains of S. cerevisiae specialized for the production of alcoholic beverages, these have been derived from natural populations unassociated with alcoholic beverage production, rather than the opposite.