Post‐glacial history and introgression in Abies (Pinaceae) species of the Russian Far East inferred from both nuclear and cytoplasmic markers

Aim The main aim of the present study is to infer the post‐glacial history of Abies species from north‐east Asia and to test the hypotheses that coastal Abies populations suffered less from climatic fluctuations during Pleistocene glacial periods than their more continental counterparts, and that Sakhalin was a major area of introgression. Location Natural ranges of the fir species Abies nephrolepis, Abies sachalinensis and Abies holophylla in the Russian Far East, and of Abies gracilis, which is endemic to the Kamchatka Peninsula. Methods Nineteen populations were sampled for allozyme analysis. Seventeen of these populations were also screened for variation at two paternally inherited chloroplast DNA microsatellite loci (cpSSR) and variation at one maternally inherited mitochondrial marker (nad4‐3/4). Finally a subset of 11 populations was analysed with amplified fragment length polymorphism (AFLP). Comparisons were made with already available Abies sibirica data. For all sets of markers, we estimated genetic diversity and differentiation using an analysis of molecular variance (AMOVA). Population clustering was assessed with a Bayesian approach implemented in structure v.2.3. Results Among the three major species, A. sibirica, A. nephrolepis and A. sachalinensis, A. sachalinensis demonstrated the highest cytoplasmic and nuclear diversity and the most continental species, A. sibirica, the lowest. Both nuclear and mitochondrial DNA markers revealed the presence of a transitional zone on Sakhalin Island between A. nephrolepis and A. sachalinensis of south Sakhalin. The structure analysis delivered very clear results confirming the admixed origin of A. sachalinensis, with a genetic contribution from A. nephrolepis. No variation in cytoplasmic markers was found in A. gracilis, suggesting the occurrence of a recent bottleneck. Main conclusions There is a clear reduction of genetic diversity in Abies species from the Pacific coast into the continent. The higher diversity in A. sachalinensis could have two causes: a larger effective population size in the islands due to relatively stable climatic conditions and consequently less pronounced demographic fluctuations in population size and/or hybridization with continental and Japanese populations. Sakhalin Island is a major transitional zone for conifer species. Finally, the fir from Kamchatka, A. gracilis, should be regarded as a separate species closely related to the A. nephrolepis–A. sachalinensis complex.     

1988 Gordon Conference on Theoretical Biology and Biomathematics Tilton Academy, Tilton, New Hampshire, U.S.A., 13–17 June 1988

Announcement

1988 Gordon Conference on Theoretical Biology and Biomathematics Tilton Academy, Tilton, New Hampshire, U.S.A., 13–17 June 1988     

Composition and structure of the antibiotic polypeptide 308-I from Actinomadura recticatena

Antibiotic 308-I isolated from Actinomadura recticatena and the products of its degradation were studied with the methods of electron impact mass spectrometry, chemical ionization with ammonia, field desorption and ion extraction from solution under atmospheric pressure. It was shown that by its composition and structure antibiotic 308-I was identical to antibiotic BBM-928 A.     

Effects of male sex hormones on specific uptake and release of 3H-serotonin in the rat hypothalamus in vitro]

With the use of "isotopic method" a study was made of the main parameters of functional activity of serotoninergic elements of hypothalamus--the specific uptake and release of 5-OT. The animals used were sexually mature rats castrated on the first postnatal day. In sexually mature intact males the specific uptake of 3H-5-OT by serotoninergic structures of the anterior hypothalamus was significantly lower than in females. Castration of animals on the first day of life resulted in the increase of specific 5-OT uptake in sexually mature males up to that observed in females. There were no differences between the sexes in the rate of spontaneous release of 5-OT. However, response to K(+)-depolarization in the anterior hypothalamus of intact males was significantly lower than that in females. In the hypothalamus of males castrated neonatally the amplitude of the response to the effect of the depolarizing agent was increase up to the level observed in females. By the results obtained it is indicated that elimination of the effect of male hormones on the first postnatal day results in the increase of 5-OT uptake and release in the hypothalamus of sexually mature rat males.     

Characterization of a new hybrid mink-mouse clone panel: chromosomal and regional assignments of the GLO,ACY, NP,CKBB, ADH2, and ME1 loci in mink (Mustela vison)

To expand the mink map, we established a new panel consisting of 23 mink-mouse clones. On the basis of statistical criteria (Wijnen et al. 1977; Burgerhout 1978), we developed a computer program for choice of clones of the panel. Assignments of the following mink genes were achieved with the use of the hybrid panel: glyoxalase (GLO), Chromosome (Chr) 1; acetyl acylase (ACY), Chr 5; creatine phosphokinase B (CKBB), Chr 10; alcohol dehydrogenase-2 (subunit B) (ADH2), Chr 8. Using a series of clones carrying rearrangements involving mink Chr 1 and 8, we assigned the gene for ME1 to the short arm of Chr 1 and that for ADH2 to Chr 8, in the region 8p12-p24. Mapping results confirm the ones we previously obtained with a mink-Chinese hamster panel. However, by means of an improved electrophoretic technique, we revised the localization of the gene for purine nucleoside phosphorylase (NP), which has been thought to be on mink Chr 2. It is reassigned to mink Chr 10.     

Assimilation of animal fats by yeasts and synthesis of protein by continuous cultivation in a complex nutrient medium

Under the conditions of continuous cultivation studies were carried out on a mixed culture (association) with two strains of yeasts: Candida sp., assimilating animal fats, and Candida scottii, assimilating reducing sugars. A complex nutrient medium of wood hydrolysate was used. It was established that in this medium, at a rate of dilution of D = 0.25 h^?1, the mixed culture assimilates the fats and the sugars simultaneously. As a result of this the yield of absolutely dry yeasts with regard to the total sum of fats and sugars amounts to 71% in the case of incineration fat and to 82% in the case of technical pork fat. The contents of protein, amino acids, lipids and ashy substances in the yeasts obtained from a medium with fats do not differ substantially from those obtained from the same medium without fats.