Effect of indole-3-acetic acid and kinetin on tuberisation parameters of different cultivars and transgenic lines of potato in vitro

The effect of indole-3-acetic acid or kinetin on the weight and numberof microtubers formed was studied on single node cuttings of sevendifferent potato (Solanum tuberosum L.) cultivars as well astransgenic lines harbouring rolB or rolC genes undercontrol of the patatin class I (B33) promoter. Plants were cultivatedin vitro in the dark on solidified MS medium containing 1 to8% sucrose with or without phytohormones. Most of thenontransformed potato cultivars and transgenic lines responded tohormone application by an increase in tuber yield. Auxin and cytokininacted differently: IAA increased predominantly the tuber size whilekinetin increased the number of tubers. RolC transformantsdisplayed an altered response to sucrose and especially to auxin. Thedegree of phytohormone effect on tuberisation parameters depended onsucrose content of the medium and potato genotype.     

Species Composition,Distribution and Ecological Features of Ichthyofauna in the Pymvashor Geothermal Valley (Bolshezemelskaya Tundra,Nenets Autonomous Okrug)

Journal of Ichthyology - Ichthyofauna in the studied streams in the Pymvashor Geothermal Valley contains six species from six families; the basis of the fish assemblage is formed by three species...     

Damage to the creatine phosphokinase of rat brain synaptosomes during molecular oxygen activation

It was shown that activation of molecular oxygen by Fe2+ ascorbate causes damage to creatine phosphokinase of rat brain synaptosomes. The creatine phosphokinase inactivation did not correlate with activation of lipid peroxidation in synaptosomes. The enzyme damage was the result of direct interaction with active oxygen species.     

One Beringian genus less: A re‐assesment of Pacifimyxas Kruglov & Starobogatov, 1985 (Mollusca: Gastropoda: Lymnaeidae) questions the current estimates of Beringian biodiversity

The taxonomic position of three nominal species of lymnaeid snails placed by Kruglov & Starobogatov (1993) into the subgenus Lymnaea (Pacifimyxas) Kruglov & Starobogatov, 1985, has been re‐assessed based on a molecular genetic study of topotypic specimens and an examination of the type series and other materials available. It has been shown that the two species, Lymnaea (Pacifimyxas) magadanensis Kruglov & Starobogatov, 1985 and Lymnaea (Pacifimyxas) streletzkajae Kruglov & Starobogatov, 1985, are identical with the species Kamtschaticana kamtschatica (Middendorff, 1850) and must be treated as its junior synonyms. Hence, Pacifimyxas becomes a junior synonym of Kamtschaticana Kruglov & Starobogatov, 1984. The taxonomic identity of the third species of Pacifimyxas, Lymnaea (Pacifimyxas) perpolita, remains obscure, and this species is considered here as taxon inquirendum. Two other nominal species, Lymnaea aberrans (Westerlund, 1897) and Lymnaea middendorffi (W. Dybowski, 1904), have been synonymized with K. kamtschatica based on morphological and geographical evidence. The lectotype of Limnaea peregra var. middendorffi is designated. The actual level of species richness in the Beringian freshwater malacofauna may be 20–25% lower than it was determined on the basis of the traditional system. Some implications of this outcome for the biogeography of the Beringian freshwater fauna are discussed.     

无症状吸烟者的肺功能改变情况分析

目的：探讨烟龄215年,日吸烟量≥15支的无症状男性吸烟者的肺功能改变情况。方法：选择男性无症状吸烟者190人及非吸烟者180人,进行肺功能测定,并比较两组人群的肺功能改变情况。结果：吸烟组与非吸烟组比较,肺活量（VC）、用力肺活量（FVC）、第1秒用力呼气容积（FEV1）、Tiffeneau1秒率（FEV1／VC）结果改变不明显,而Gaensler1秒率（FEV1/FVC）、最大分钟通气量（MVV）、用力呼气50％肺活量的呼气流量（FEF50％）、用力呼气75％肺活量的呼气流量（FEF75％）、呼出25％-75％肺活量时的平均流量（FEF25％～75％）、肺一氧化碳弥散量（DLCO）结果均有显著降低,有统计学意义。结论：通过对无症状吸烟人群肺功能测定结果进行分析。发现有些吸烟者虽无临床症状,但已经出现了小气道及肺弥散功能的损伤,提醒吸烟者应早期戒烟,关爱自身健康,净化生存环境,提高生活质量。     

Phenotypic expression of epigenetic determinant [ISP +] in Saccharomyces cerevisiae depends on the combination of sup35 and sup45 mutations

Translation fidelity in Saccharomyces yeasts is determined by genetic and epigenetic (prion) factors. A study was made of S. cerevisiae strains containing the nonchromosomal determinant [ISP ⁺], described earlier. Some of its properties suggest that [ISP ⁺] is a prion. [ISP ⁺] is expressed phenotypically as an antisuppressor of two sup35 mutations and can be cured with guanidine chloride (GuHCl). It was shown that sup35 mutants containing [ISP ⁺] carried additional sup45 mutations. These mutations caused amino acid substitutions in different regions of translation termination factor eRF1, encoded by SUP45. Strains bearing the sup35-25 mutation contained the sup45 mutation that caused amino acid substitution at position 400 of eRF1; strains bearing sup35-10 contained the mutation that altered eRF1 at position 75. Thus, the antisuppressor phenotype of the [ISP ⁺] strains proved to depend on the interaction of sup35 and sup45 mutations, as well as on the GuHCl-curable epigenetic determinant. Published in Russian in Molekulyarnaya Biologiya, 2006, Vol. 40, No. 5, pp. 844–849. The article was translated by the authors.     

Novel non-Mendelian determinant involved in the control of translation accuracy in Saccharomyces cerevisiae.

Two cytoplasmically inherited determinants related by their manifestation to the control of translation accuracy were previously described in yeast. Cells carrying one of them, [PSI(+)], display a nonsense suppressor phenotype and contain a prion form of the Sup35 protein. Another element, [PIN(+)], determines the probability of de novo generation of [PSI(+)] and results from a prion form of several proteins, which can be functionally unrelated to Sup35p. Here we describe a novel nonchromosomal determinant related to the SUP35 gene. This determinant, designated [ISP(+)], was identified as an antisuppressor of certain sup35 mutations. We observed its loss upon growth on guanidine hydrochloride and subsequent spontaneous reappearance with high frequency. The reversible curability of [ISP(+)] resembles the behavior of yeast prions. However, in contrast to known prions, [ISP(+)] does not depend on the chaperone protein Hsp104. Though manifestation of both [ISP(+)] and [PSI(+)] is related to the SUP35 gene, the maintenance of [ISP(+)] does not depend on the prionogenic N-terminal domain of Sup35p and Sup35p is not aggregated in [ISP(+)] cells, thus ruling out the possibility that [ISP(+)] is a specific form of [PSI(+)]. We hypothesize that [ISP(+)] is a novel prion involved in the control of translation accuracy in yeast.