Saccharomyces eubayanus and Saccharomyces arboricola reside in North Island native New Zealand forests

Saccharomyces is one of the best‐studied microbial genera, but our understanding of the global distributions and evolutionary histories of its members is relatively poor. Recent studies have altered our view of Saccharomyces’ origin, but a lack of sampling from the vast majority of the world precludes a holistic perspective. We evaluate alternate Gondwanan and Far East Asian hypotheses concerning the origin of these yeasts. Being part of Gondwana, and only colonized by humans in the last ～1000 years, New Zealand represents a unique environment for testing these ideas. Genotyping and ribosomal sequencing of samples from North Island native forest parks identified a widespread population of Saccharomyces. Whole genome sequencing identified the presence of S. arboricola and S. eubayanus in New Zealand, which is the first report of S. arboricola outside Far East Asia, and also expands S. eubayanus’ known distribution to include the Oceanic region. Phylogenomic approaches place the S. arboricola population as significantly diverged from the only other sequenced Chinese isolate but indicate that S. eubayanus might be a recent migrant from South America. These data tend to support the Far East Asian origin of the Saccharomyces, but the history of this group is still far from clear.     

Heterosis in crosses between lines of Drosophila melanogaster selected for adaptation to different environments

Summary Experiments were designed to examine whether heterosis would occur in crosses of Drosophila melanogaster populations adapted to 18 °C or 28 °C environments. Crosses were examined in parental environments, an intermediate environment (23 °C) and a mixed environment (alternating 18°/28°C). Parental populations did not show divergence for larval viability, cold shock or high temperature mortalities when tested in a common environment. However, the 28 °C population was less fecund than the 18 °C population, but had higher larval competitive ability and higher adult longevity. Heterosis for viability, cold shock mortality and high temperature mortality occurred in crosses between a population adapted to 18 °C and another adapted to 28 °C, but not in crosses between two populations adapted to the same temperature. The results suggest that, in the absence of drift, heterosis is expected in crosses between lines or populations with different histories of selection but not between lines with the same selection histories.     

The effect of weight on intravaginal pressure and vulval conformation of mares

Pressures were recorded monthly at two sites in the vaginas of nine horse mares with normal vulval conformation. The pressures were lowest when the mares' weights were minimal, and there was evidence of a descending pressure gradient from the vestibule to the cervix. Loss of body weight was also associated with shortening and angulation of the vulva, although it was not displaced above the pelvic brim.     

Repair and mutagenesis of herpes simplex virus in UV-irradiated monkey cells

Mutagenic repair in mammalian cells was investigated by determining the mutagenesis of UV-irradiated or unirradiated herpes simplex virus in UV-irradiated CV-1 monkey kidney cells. These results were compared with the results for UV-enhanced virus reactivation (UVER) in the same experimental situation. High and low multiplicities of infection were used to determine the effects of multiplicity reactivation (MR). UVER and MR were readily demonstrable and were approximately equal in amount in an infectious center assay. For this study, a forward-mutation assay was developed to detect virus mutants resistant to iododeoxycytidine (ICdR), probably an indication of the mutant virus being defective at its thymidine kinase locus. ICdR-resistant mutants did not have a growth advantage over wild-type virus in irradiated or unirradiated cells. Thus, higher fractions of mutant virus indicated greater mutagenesis during virus repair and/or replication. The data showed that: (1) unirradiated virus was mutated in unirradiated cells, providing a background level of mutagenesis; (2) unirradiated virus was mutated about 40% more in irradiated cells, indicating that virus replication (DNA synthesis?) became more mutagenic as a result of cell irradiation; (3) irradiated virus was mutated much more (about 6-fold) than unirradiated virus, even in unirradiated cells; (4) cell irradiation did not change the mutagenesis of irradiated virus except at high multiplicity of infection. High multiplicity of infection did not lead to higher mutagenesis in unirradiated cells. Thus the data did not demonstrate UVER or MR alone to be either error-free or error-prone. When the two processes were present simultaneously, they were mutagenic.     

Construction and regional localization of clones from a NotI linking library from human chromosome 17q

A NotI linking library was constructed from a somatic cell hybrid containing chromosome 17q as its only human material. A total of 112 human clones were assigned to nine regions of 17q using a somatic cell hybrid mapping panel. The library includes clones that detect the acute promyelocytic leukemia and von Recklinghausen neurofibromatosis translocation breakpoints at 17q11.2-12 and 17q11.2, respectively, on pulsed-field gel electrophoresis. The mapped clones represent over 50% of the estimated number of NotI sites on 17q, and therefore constitute an important resource for long-distance mapping.     

Identification of N-myristoylated proteins by reverse-phase high performance liquid chromatography of an azlactone derivative of N-myristoylglycine.

A method is presented for the identification of N-myristoylated proteins. N-Myristoyl transferases have an absolute requirement for a free N-terminal glycine. N-Myristoylglycine is released upon mild acid hydrolysis of myristoylated peptides and proteins and its derivitization to a p-nitrobenzylazlactone with subsequent analysis by reverse phase h.p.l.c. enabled its detection to pmol levels. This facilitated the identification of N-terminal myristate in nmol quantities of purified proteins. Using this method we demonstrate that the alpha-subunit of the GTP-binding protein G0 is N-terminally myristoylated.     

Anterior vaginal and intrauterine pressures in mares

Resting pressure in the anterior vagina and uterus was measured monthly in eight mares for 5 mo. During this time, four of the mares maintained their body weight and four lost weight. Mean anterior vaginal pressure was -11.9 mmHg, and intrauterine pressure was -5.3 mmHg; the latter was positively correlated to body weight and weight/height ratio. Anterior vaginal pressure and uterine pressure were also positively correlated. Allowing air into the anterior vagina raised this pressure to -4.0 mmHg, i.e. higher than uterine pressure. There was a tendency for genital tract pressures to be lower in anoestrous mares than those which remained cyclic. Some physiological events caused marked increases in genital pressures.