Direct selection ofPichia pastoris expression strains using new G418 resistance vectors

Confectionery sunflower - a special area of use of sunflower, which requires the creation of marketable seeds quality features. One of the possible ways to create large-fruited sunflower is to create production hybrids and lines. Objective: to evaluate the created new large-fruited sunflower lines by a complex of morphological characters and determine the best lines for use as large-seeds hybrids as parent components or source material. In 2016-2019 years on the basis of the Institute of Oilseed Crops NAAS a study was conducted to assess the economic characteristics of large-fruited sunflower lines. We studied a collection of 27 lines of large-seeds sources. The lines were created by direct selection or crossing and sampling: Reyny of Argentinean origin, Zaporizhzhya confectionery variety, confectionery hybrid with striped pericarp color of Israeli origin, white seed of Turkish origin, synthetic population - donor of complex resistance. To study from the collection, lines were drawn that went through at least 7 generations with selection for seed size. Experience has shown that the shortest growing season for lines 174d and KP11 was 99 days, and the longest for lines I2K670 was 109 days. In the studied collection, the greatest mass of 1000 seeds has the KP11-146.47g line, which is the mother component and does not have branching. The second by weight of 1000 seeds (109 g) stood out line 168v, which also had branches and pollen fertility restoration genes and will be used as the paternal form. The third largest is also one basket line ZKN51-100. The collection included lines originating from the same combination, but with a different morphotype for the presence and absence of branching. So, based on the combination of KP11 x Zaporizhzhya Confectionery, three lines were obtained. A mass of 1000 seeds was observed in 98-86 g, with the branching line having the largest mass of 1000 seeds. The lines created with one combination VK678 x ZKN32: with a branch 168a had a mass of 1000 seeds 95g, and a line 168b - without a branch 109 g. Of the two lines obtained from the descendants of the combination KP11 x the striped hybrid both had branches, but the seeds were much smaller (weight of 1000 seeds 59 and 79 g). The collection also studied samples created on the basis of varieties and populations 160c, 174, 175b, the mass of 1000 seeds of which turned out to be more acceptable for large-fruited use from 83 to 99 g. Summing up the results of studying the collection of newly created lines, we can highlight the lines 162d, 168v, 175b, KP11 that are potentially promising for use in hybrids. The selections showed that large-fruited lines can be obtained from large-fruited varieties, self-pollination of large-fruited hybrids and crossing lines with hybrids and varieties. Self-pollination and selection of large-fruited lines in several generations does not provide the necessary variability for positive changes in selections. The result of the selection by weight of 1000 seeds in the offspring from crosses and from populations creates opportunities for new large-seeds sunflower.

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Protogyny in Autumn Migration: Do Male Birds ”Play Chicken”?

The Auk ◽

10.1093/auk/122.1.71 ◽

2005 ◽

Vol 122 (1) ◽

pp. 71-81 ◽

Cited By ~ 4

Author(s):

Alexander M. Mills

Keyword(s):

Migratory Birds ◽

Indirect Selection ◽

Male Competition ◽

Autumn Migration ◽

Direct Selection ◽

Differential Migration ◽

The North ◽

Parsimonious Explanation ◽

Ground Conditions ◽

Wintering Ground

AbstractProtandry, the earlier arrival of males than of females on breeding areas, occurs in many taxa, including many migratory birds. Numerous hypotheses have been generated to explain protandry. Using bird-banding records, I show that protogyny, the earlier migration of females, frequently occurs in the autumn, though it is less universal and less dramatic than spring protandry. In one species, it occurs in both hatch-year and adult birds. When (1) spring and autumn, (2) departures and arrivals, and (3) breeding and wintering ground conditions are considered, hypotheses generated only to explain spring protandry can be more thoroughly evaluated. Using that approach, the most parsimonious explanation of differential migration between the sexes explains earlier male arrival in spring and later male departure in autumn through either (1) indirect selection operating on intrasexual male competition for territories or (2) direct selection operating on intersexual relations requiring males to be present on breeding territories when females are present. In autumn-protogynous species, males may ”play chicken,” balancing the benefits of remaining longer than females and protecting territories for subsequent years against the costs of remaining in the north under deteriorating conditions and delaying the acquisition of a good winter territory.Protogynie et migration automnale: Est-ce que les mâles ”jouent les dégonflés”?

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Positive Selection of Novel Peroxisome Biogenesis-Defective Mutants of the Yeast Pichia pastoris

Genetics ◽

10.1093/genetics/151.4.1379 ◽

1999 ◽

Vol 151 (4) ◽

pp. 1379-1391

Author(s):

Monique A Johnson ◽

Hans R Waterham ◽

Galyna P Ksheminska ◽

Liubov R Fayura ◽

Joan Lin Cereghino ◽

...

Keyword(s):

Pichia Pastoris ◽

Allyl Alcohol ◽

Alcohol Oxidase ◽

Methylotrophic Yeast ◽

Direct Selection ◽

Toxic Exposure ◽

Peroxisome Biogenesis ◽

Yeast Pichia Pastoris ◽

Methylotrophic Yeast Pichia Pastoris ◽

Selection Of

Abstract We have developed two novel schemes for the direct selection of peroxisome-biogenesis-defective (pex) mutants of the methylotrophic yeast Pichia pastoris. Both schemes take advantage of our observation that methanol-induced pex mutants contain little or no alcohol oxidase (AOX) activity. AOX is a peroxisomal matrix enzyme that catalyzes the first step in the methanol-utilization pathway. One scheme utilizes allyl alcohol, a compound that is not toxic to cells but is oxidized by AOX to acrolein, a compound that is toxic. Exposure of mutagenized populations of AOX-induced cells to allyl alcohol selectively kills AOX-containing cells. However, pex mutants without AOX are able to grow. The second scheme utilizes a P. pastoris strain that is defective in formaldehyde dehydrogenase (FLD), a methanol pathway enzyme required to metabolize formaldehyde, the product of AOX. AOX-induced cells of fld1 strains are sensitive to methanol because of the accumulation of formaldehyde. However, fld1 pex mutants, with little active AOX, do not efficiently oxidize methanol to formaldehyde and therefore are not sensitive to methanol. Using these selections, new pex mutant alleles in previously identified PEX genes have been isolated along with mutants in three previously unidentified PEX groups.

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Adaptive evolvability through direct selection instead of indirect, second‐order selection

Journal of Experimental Zoology Part B Molecular and Developmental Evolution ◽

10.1002/jez.b.23071 ◽

2021 ◽

Author(s):

Andreas Wagner

Keyword(s):

Second Order ◽

Direct Selection ◽

Order Selection

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GENETIC CONTROL OF VARIATION IN A SELECTED POPULATION OF RUSSIAN WILD RYEGRASS (ELYMUS JUNCEUS)

Canadian Journal of Plant Science ◽

10.4141/cjps76-043 ◽

1976 ◽

Vol 56 (2) ◽

pp. 275-280

Author(s):

T. LAWRENCE

Keyword(s):

Genetic Control ◽

Seed Yield ◽

Seed Weight ◽

Dry Matter ◽

Recurrent Selection ◽

Direct Selection ◽

Adult Plant ◽

Dry Matter Yield ◽

Seedling Characters ◽

Additive Control

Progenies from a five-genotype diallel cross in Russian wild ryegrass, Elymus junceus Fisch., were studied to assess the pattern of genetic control for F1 seed weight and a number of seedling and adult plant characters. Variation in F1 seed weight was largely determined by the maternal parent, but some control by the pollen parent was apparent. Of the seedling characters, days to emerge, rate of leaf appearance, rate of tiller appearance, and seedling dry matter yield, only days to emerge showed additive variance which is amenable to direct selection. The other three characters could be most easily exploited by a recurrent selection program. The adult plant characters, date of inflorescence appearance, P content of the forage, and organic matter digestibility indicated strong additive control which is amenable to direct selection. Dry matter yield and seed yield also showed strong additive control which was accompanied by specific combining ability and weak maternal effects suggesting good progress should be possible by direct selection methods but crossing the selections in a diallel fashion prior to formation of synthetics might be desirable. The seedling characters, rate of leaf and tiller appearance and seedling dry matter yield were interrelated and associated with adult plant yield, thus offering the possibility of screening seedlings for these characters in a recurrent selection program for improved forage or seed yield.

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A sensitive immunoassay for rat fatty acid translocase (CD36) using phage antibodies selected on cell transfectants: abundant presence of fatty acid translocase/CD36 in cardiac and red skeletal muscle and up-regulation in diabetes

Biochemical Journal ◽

10.1042/bj3370407 ◽

1999 ◽

Vol 337 (3) ◽

pp. 407-414 ◽

Cited By ~ 22

Author(s):

Maurice M. A. L. PELSERS ◽

Jan T. LUTGERINK ◽

Frans A. van NIEUWENHOVEN ◽

Narendra N. TANDON ◽

Ger J. van der VUSSE ◽

...

Keyword(s):

Fatty Acid ◽

Membrane Protein ◽

Diabetic Rats ◽

Direct Selection ◽

Antibody Library ◽

Fatty Acid Binding ◽

Fatty Acid Translocase ◽

Phage Antibody ◽

Phage Antibodies ◽

Set Up

The rat membrane protein fatty acid translocase (FAT), which shows sequence similarity to human CD36 (a membrane protein supposedly involved in a variety of membrane processes), is implicated in the transport of long-chain fatty acids across cellular membranes. To set up an immunoassay for quantification of FAT in different tissues, we isolated a series of anti-FAT antibodies by panning a large naive phage antibody library on FAT-transfected H9c2 cells. All seven different phage antibody fragments isolated reacted specifically with FAT, and most likely recognize the same or closely located immunodominant sites on FAT, as a competitive monoclonal antibody (mAb) (CLB-IV7) completely blocked the binding of all these phage antibodies to cells. A sandwich ELISA was set up using mAb 131.4 (directed against purified CD36 from human platelets) as capture antibody and phage antibodies and anti-phage sera as detector. With this ELISA (sensitivity 0.05 µg/ml), the FAT content in isolated cardiomyocytes was found to be comparable with that of total heart (≈ 3 mg/g of protein), while liver tissue and endothelial cells were below the detection limit (< 0.1 mg of FAT/g of protein). During rat heart development, protein levels of FAT rose from 1.7±0.7 mg/g of protein on the day before birth to 3.6±0.4 mg/g of protein on day 70. Comparing control with streptozotocin-induced diabetic rats, a statistically significant (P< 0.05) 2–4-fold increase of FAT was seen in heart (from 4.2±2.3 to 11.0±5.7 mg/g of protein), soleus (from 0.6±0.1 to 1.4±0.5 mg/g of protein) and extensor digitorum longus (EDL) muscle (from 0.3±0.1 to 1.2±0.8 mg/g of protein). In addition, the FAT contents of each of these muscles were found to be of similar magnitude to the contents of cytoplasmic heart-type fatty-acid-binding protein in both diabetic rats and controls, supporting the suggested roles of these two proteins in cellular fatty acid metabolism. This is the first time phage display technology has been succesfully applied for direct selection, from a large naive antibody library, of antibodies that recognize selected membrane proteins in their natural context.

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