Annual cycle of liveweight and reproductive changes of farmed male fallow deer (Dama dama) and the effect of daily oral administration of melatonin in summer on the attainment of seasonal fertility

Entire bucks (N = 7) exhibited pronounced liveweight gains over spring and summer months (October-February), to reach a peak mean weight of 59.8 kg, and rapid liveweight losses over the rutting period (April-May) with a minimum mean liveweight of 54.2 kg. Mean neck girth and serum testosterone levels increased during late summer (January-March) and peaked at 387 mm and 12 ng/ml respectively immediately before the onset of the rut (April). Thereafter both measures declined during winter and spring months (June-December). Bucks castrated prepubertally (N = 11) exhibited similar but less pronounced changes in mean liveweight and neck girth, in the absence of any change in testosterone secretion. Peak mean testicular diameter of entire bucks (39 mm) occurred immediately before the rut and was followed by testicular regression over winter and spring months (June-November), such that the testes attained their minimum mean size of 18 mm diameter in early summer (November). Motile spermatozoa were absent from ejaculates collected in summer (November 1983, 1984; January 1984). However, ejaculates collected pre-rut (late March), immediately post-rut (June) and in early spring (September) contained successively increasing numbers of motile spermatozoa. A further 14 polled, entire bucks were given orally 5 mg (N = 7; Group A) or 20 mg (N = 7; Group B) melatonin at 15:30 h daily from 1 December 1983 to 14 January 1984 (45 days). Seven control bucks (Group C) received vehicle ration only. The measurements taken for bucks in Groups A and B were not significantly different (P greater than 0.1) on any sampling date and the data for these 2 groups were pooled. Mean serum testosterone concentrations and mean ejaculate volume were not significantly different between melatonin-treated and control bucks on any sampling date, although other measures exhibited significant differences (P less than 0.05) at various treatment or post-treatment dates: melatonin-treated bucks showed a transiently greater increase in neck muscle development during and immediately after treatment, a slight retardation of liveweight gain between 45 and 75 days after treatment, an earlier peak in maximum mean testicular diameter and an earlier onset of sperm presence in ejaculates.     

Sequence of the short unique region, short repeats, and part of the long repeats of human cytomegalovirus

We have determined the DNA sequence (46 kilobases) of the short unique region, the short repeat, and part of the long repeat of human cytomegalovirus strain AD169. Analysis of the sequence has revealed at least 38 possible regions that may code for protein. Many of these open reading frames show homology to each other, and five groups of homologous reading frames are identified. Half of the predicted translation products appear to be membrane proteins, and fall into two distinct classes; those that have potential signal and anchor sequences, and those that have seven potential membrane-spanning regions and appear to be integral membrane proteins. A number of the former class contain sites for N-linked glycosylation and may therefore be glycoproteins. None of the 38 open reading frames shows homology to other known herpesvirus proteins.     

DNA sequencing: present limitations and prospects for the future

As the human genome program gets under way, we examine the progress made since the first human genome meeting in Santa Cruz in 1985. The lessons of the last 5 years demonstrate that progress has been much slower than anticipated. The new technology being developed in 1985 was fluorescent sequencing and multiplexing. These techniques are now established, but they still have to produce a substantial sequence to rival those determined by conventional technology. Inspection of the EMBL and GenBank databases shows few large sequences have been determined and that there is a large discrepancy between what is theoretically possible and what has been achieved so far.     

SCP1, a 356,023 bp linear plasmid adapted to the ecology and developmental biology of its host, Streptomyces coelicolor A3(2)

The sequencing of the entire genetic complement of Streptomyces coelicolor A3(2) has been completed with the determination of the 365,023 bp sequence of the linear plasmid SCP1. Remarkably, the functional distribution of SCP1 genes somewhat resembles that of the chromosome: predicted gene products/functions include ECF sigma factors, antibiotic biosynthesis, a gamma-butyrolactone signalling system, members of the actinomycete-specific Wbl class of regulatory proteins and 14 secreted proteins. Some of these genes are among the 18 that contain a TTA codon, making them targets for the developmentally important tRNA encoded by the bldA gene. RNA analysis and gene fusions showed that one of the TTA-containing genes is part of a large bldA-dependent operon, the gene products of which include three proteins isolated from the spore surface by detergent washing (SapC, D and E), and several probable metabolic enzymes. SCP1 shows much evidence of recombinational interactions with other replicons and transposable elements during its history. For example, it has two sets of partitioning genes (which may explain why an integrated copy of SCP1 partially suppressed the defective partitioning of a parAB-deleted chromosome during sporulation). SCP1 carries a cluster of probable transfer determinants and genes encoding likely DNA polymerase III subunits, but it lacks an obvious candidate gene for the terminal protein associated with its ends. This may be related to atypical features of its end sequences.     

Cardiovascular GO Annotation Initiative Year 1 Report: Why Cardiovascular GO?

Gene Ontology (GO) vocabularies are an established standard for linking functional information to genes and gene products (www.geneontology.org/). A recent collaboration between University College London and the European Bioinformatics Institute is providing GO annotation to human cardiovascular-associated genes (http://www.ucl.ac.uk/medicine/cardiovascular-genetics/geneontology.html). This report outlines the aims of this collaboration and summarizes how the cardiovascular community can help improve the quality and quantity of GO annotations. This new initiative is funded by the British Heart Foundation and fully supported by the GO Consortium.     

Alternative selectable markers for potato transformation using minimal T-DNA vectors

Alternative selection systems for plant transformation are especially valuable in clonal crops, such as potato (Solanum tuberosum L.), to pyramid transgenes into the same cultivar by successive transformation events. We have modified the pGPTV series of binary vectors to construct pMOA1 to pMOA5, resulting in a series of essentially identical binary vectors except for the presence of different selectable marker genes. These selectable marker genes are tightly inserted between the left and right T-DNA borders and confer resistance to kanamycin (nptII), hygromycin (hpt), methotrexate (dhfr), phosphinothricin (bar), or phleomycin (ble). The T-DNA of all the vectors is based on the minimal features necessary for plant transformation, with no extraneous DNA segments that may be unacceptable to regulatory authorities for general release of transgenic plants. A series of unique restriction sites exists between the right border and each selectable marker gene for subsequent insertion of useful genes. We have also developed improved culture procedures for potato transformation and used the pMOA1 to pMOA5 binary vectors to define stringent selection conditions for each marker gene. Combining these advances improved the frequency of recovering transformed potato plants while maintaining a low frequency of escapes. The relative efficiency of recovering transgenic potato lines with each selectable marker gene can be summarised as: kanamycin resistance>hygromycin resistance>phosphinothricin resistance>phleomycin resistance>methotrexate resistance.