scholarly journals Metabolism of aged seeds. Changes in rye embryo polyribosomes during seed aging

2014 ◽  
Vol 61 (3-4) ◽  
pp. 369-379
Author(s):  
Kazimierz Zalewski
Keyword(s):  
Dehydrogenase Activity ◽  
Ribosomal Proteins ◽  
Control Sample ◽  
Electrophoretic Analysis ◽  
Winter Rye ◽  
Control Embryo ◽  
Ribonucleic Acids ◽  
Seed Aging ◽  
Almost All ◽  
Aged Seeds

Germination, total dehydrogenase activity, ribosomal proteins and ribonucleic acids of embryos obtained from winter rye harvested in different years and of distinctly differing viability were studied. Diminishing viability was accompanied by declines in the amount of ribosome-bound mRNA and a drop in the intensity of its synthesis during germination. Electrophoretic analysis of control embryo (fully viable) ribosome proteins revealed 55 different bands: 10 acidic and 45 basic. The embryos of aged seeds had 43 different bands of which 8 were acidic, 35 basic and almost all of which had an altered electrophoretic mobility as compared with the control sample. As aging progressed, the percentages of lysine, histidine and arginine increased while those of tyrosine, methionine, proline and serine decreased.

scholarly journals The effect of the plant growth retardants AMO-1618 and CCC on the synthesis of ribonucleic acids and proteins in triticale embryos during the initial phase of germination

2014 ◽  
Vol 56 (2) ◽  
pp. 303-314 ◽  
Author(s):  
Stanisław Weidner
Keyword(s):  
Ribosomal Proteins ◽  
Protein Biosynthesis ◽  
Control Sample ◽  
Methyl Chloride ◽  
Gibberellin Biosynthesis ◽  
Trimethylammonium Chloride ◽  
Germination Capacity ◽  
Growth Retardants ◽  
Ribonucleic Acids ◽  
Amo 1618

Triticale var. Grado caryopses were subjected to imbibition and germination in the presence of the growth retardants, AMO-1618 (2-isopropyl-4-dimethylamino-5-methylphenyl-1-piperidinecarboxylate methyl chloride) and CCC (2-chloroethyl)-trimethylammonium chloride) at the following concentrations, 3 x 10<sup>-4</sup> M and 10<sup>-3</sup> M. These compounds exerted a very strong inhibitory effect on the initiation of germination processes, growth of embryos and the germination capacity of the caryopses. At the concentration of 10<sup>-3</sup> M, AMO-1618 showed an especially strong effect, lowering the germination capacity of the caryopses to about 50%. It was also shown that both retardants are decidedly more effective on the germination of whole, intact caryopses than on that of isolated embryos. During the very earliest hours of germination, these retardants already inhibited RNA synthesis. The participation of the polyribosome fraction in the total ribosome fraction of embryos in the control sample after 24 hrs of germination of caryopses equalled about 70%, while in the samples treated with CCC (10<sup>-3</sup> M)- about 57%, in the samples treated with AMO-1618 (10<sup>-3</sup> M) about 35%,. The inhibition of incorporation of <sup>14</sup>C-amino acids into ribosomal proteins in the polyribosome fraction was in the case of CCC about 13%, while in the samples treated with AMO-1618, about 55%. In the monosome fraction (80S), the inhibition by CCC was about 23%, whereas in the samples treated with AMO-1618 it reached around 73%. From this data it is evident that the studied retardants have a significant influence on the synthesis of ribonucleic acids as well as on ribosome proteins. These results also suggest the existance of another mechanism, aside from that of inhibition of gibberellin biosynthesis, inhibiting the growth and development of cells. The high percentage of ribosome subunits in the samples treated with CCC, in comparison with controls and samples treated with AMO-1618, points to different mechanisms by which these two compounds affect protein biosynthesis.

scholarly journals The metabolism of aged seeds. The involvement of the pentose phosphate pathway in respiration in germinating rye grains of various ages

2014 ◽  
Vol 61 (2) ◽  
pp. 167-175 ◽  
Author(s):  
Kazimierz Zalewski
Keyword(s):  
Dehydrogenase Activity ◽  
Pentose Phosphate Pathway ◽  
Growth Analysis ◽  
Krebs Cycle ◽  
Pentose Phosphate ◽  
Seed Vigor ◽  
Winter Rye ◽  
Oxidation Of Glucose ◽  
Aged Seeds

Winter rye grains from different harvest years (having distinctly different viabilities) were studied in terms of germination, total dehydrogenase activity and growth analysis. Reduction of seed vigor and viability was accompanied by a decrease in the intensity of embryo respiration during germination. The use of (1-<sup>14</sup>C) glucose and (6-<sup>14</sup>C) glucose showed that germinating rye embryos catabolize glucose through glycolysis, Krebs cycle and the pentose phosphate pathway. It was also shown that the C<sub>6</sub>/C<sub>1</sub> ratio in respiring embryos initially increased during the first 48 hours of germination, then dropped, which suggests a mounting contribution of the PP pathway to the overall cotabolism. The oxidation of glucose in, embryos from the most deteriorated grains proceeded through glycolysis and Krebs cycle only.

scholarly journals The metabolism of aged seeds. The free and membrane-bound polyribosomes of germinating rye grains of different ages

2014 ◽  
Vol 57 (2) ◽  
pp. 261-270
Author(s):  
Kazimierz Zalewski
Keyword(s):  
Ribosomal Proteins ◽  
Specific Radioactivity ◽  
Winter Rye ◽  
Different Ages ◽  
Membrane Bound ◽  
Radioactivity Levels ◽  
Aged Seeds

Grains of winter rye harvested in 1976, 1978, 1982 and 1984 were studied. Free and membrane-bound polyribosomes were isolated from embryos of imbibing and germinating grains. There was no correlation between grain viability and the amout of ribosomes. The highest incorporation of radioactive precursors (both total and specific radioactivity) was found in the RNA and ribosomal proteins from the grains with the highest viability - harvested in 1984. Lower radioactivity levels were observed in the 2 to 6 year old grains. There was no incorporation of radioactive precursors into ribosomal proteins in dead seeds.

scholarly journals Barley Seeds miRNome Stability during Long-Term Storage and Aging

2021 ◽  
Vol 22 (9) ◽  
pp. 4315
Author(s):  
Marta Puchta ◽  
Jolanta Groszyk ◽  
Magdalena Małecka ◽  
Marek D. Koter ◽  
Maciej Niedzielski ◽  
...  
Keyword(s):  
Seed Viability ◽  
Small Rna Sequencing ◽  
The Novel ◽  
Seed Aging ◽  
Long Term Storage ◽  
Novel Mirna ◽  
Complex Biological Process ◽  
Almost All ◽  
Term Storage

Seed aging is a complex biological process that has been attracting scientists’ attention for many years. High-throughput small RNA sequencing was applied to examine microRNAs contribution in barley seeds senescence. Unique samples of seeds that, despite having the same genetic makeup, differed in viability after over 45 years of storage in a dry state were investigated. In total, 61 known and 81 novel miRNA were identified in dry seeds. The highest level of expression was found in four conserved miRNA families, i.e., miR159, miR156, miR166, and miR168. However, the most astonishing result was the lack of significant differences in the level of almost all miRNAs in seed samples with significantly different viability. This result reveals that miRNAs in dry seeds are extremely stable. This is also the first identified RNA fraction that is not deteriorating along with the loss of seed viability. Moreover, the novel miRNA hvu-new41, with higher expression in seeds with the lowest viability as detected by RT-qPCR, has the potential to become an indicator of the decreasing viability of seeds during storage in a dry state.

scholarly journals The effect of hypermethylation on the functional properties of transfer ribonucleic acid. Formation of aminoacyl-transfer-ribonucleic acid

1969 ◽  
Vol 114 (2) ◽  
pp. 429-435 ◽  
Author(s):  
David J. Pillinger ◽  
John Hay ◽  
Ernest Borek
Keyword(s):  
Amino Acids ◽  
Ribonucleic Acid ◽  
Control Sample ◽  
Transfer Rna ◽  
E Coli ◽  
Functional Sites ◽  
The Individual ◽  
Almost All ◽  
Aminoacyl Transfer ◽  
Kinetics Of

1. The ability of chemically hypermethylated Escherichia coli B transfer RNA to accept 19 amino acids was studied and the results were compared with those obtained with a control sample of E. coli B transfer RNA incubated under similar conditions in the absence of methylating agent. 2. There is a marked decrease in the ability of the modified transfer RNA to accept amino acids in almost all instances. 3. The acceptance of cysteine appears to be unique in that it is enhanced in the hypermethylated transfer RNA. 4. More detailed studies on the kinetics of acceptance for six amino acids is presented, emphasizing the variation in response of the individual amino acids. 5. Increasing hypermethylation causes a progressive decrease in the amino acid acceptance. 6. The results are discussed in terms of methylation at functional sites within the transfer RNA and possible conformational alterations to the structure of the macromolecule.

scholarly journals Genome-Wide Identification, Evolution and Expression of the Complete Set of Cytoplasmic Ribosomal Protein Genes in Nile Tilapia

2020 ◽  
Vol 21 (4) ◽  
pp. 1230
Author(s):  
Gangqiao Kuang ◽  
Wenjing Tao ◽  
Shuqing Zheng ◽  
Xiaoshuang Wang ◽  
Deshou Wang
Keyword(s):  
Ribosomal Proteins ◽  
Nile Tilapia ◽  
Ribosome Biogenesis ◽  
Developmental Stages ◽  
Expression Profiles ◽  
Ribosomal Protein Genes ◽  
Expression Levels ◽  
Sexually Dimorphic Expression ◽  
Complete Set ◽  
Almost All

Ribosomal proteins (RPs) are indispensable in ribosome biogenesis and protein synthesis, and play a crucial role in diverse developmental processes. In the present study, we carried out a comprehensive analysis of RPs in chordates and examined the expression profiles of the complete set of 92 cytoplasmic RP genes in Nile tilapia. The RP genes were randomly distributed throughout the tilapia genome. Phylogenetic and syntenic analyses revealed the existence of duplicated RP genes from 2R (RPL3, RPL7, RPL22 and RPS27) and 3R (RPL5, RPL19, RPL22, RPL41, RPLP2, RPS17, RPS19 and RPS27) in tilapia and even more from 4R in common carp and Atlantic salmon. The RP genes were found to be expressed in all tissues examined, but their expression levels differed among different tissues. Gonadal transcriptome analysis revealed that almost all RP genes were highly expressed, and their expression levels were highly variable between ovaries and testes at different developmental stages in tilapia. No sex- and stage-specific RP genes were found. Eleven RP genes displayed sexually dimorphic expression with nine higher in XY gonad and two higher in XX gonad at all stages examined, which were proved to be phenotypic sex dependent. Quantitative real-time PCR and immunohistochemistry ofRPL5b and RPL24 were performed to validate the transcriptome data. The genomic resources and expression data obtained in this study will contribute to a better understanding of RPs evolution and functions in chordates.

scholarly journals Isolation of Poly-3-Hydroxybutyrate Metabolism Genes from Complex Microbial Communities by Phenotypic Complementation of Bacterial Mutants

2006 ◽  
Vol 72 (1) ◽  
pp. 384-391 ◽  
Author(s):  
Chunxia Wang ◽  
David J. Meek ◽  
Priya Panchal ◽  
Natalie Boruvka ◽  
Frederick S. Archibald ◽  
...  
Keyword(s):  
Microbial Communities ◽  
Dehydrogenase Activity ◽  
Sinorhizobium Meliloti ◽  
Soil Microbial Communities ◽  
Nucleic Acid Hybridization ◽  
Broad Host Range ◽  
Soil Microbial ◽  
Bacterial Mutants ◽  
Mutant Host ◽  
Almost All

ABSTRACT The goal of this study was to initiate investigation of the genetics of bacterial poly-3-hydroxybutyrate (PHB) metabolism at the community level. We constructed metagenome libraries from activated sludge and soil microbial communities in the broad-host-range IncP cosmid pRK7813. Several unique clones were isolated from these libraries by functional heterologous complementation of a Sinorhizobium meliloti bdhA mutant, which is unable to grow on the PHB cycle intermediate d-3-hydroxybutyrate due to absence of the enzyme d-3-hydroxybutyrate dehydrogenase activity. Clones that conferred d-3-hydroxybutyrate utilization on Escherichia coli were also isolated. Although many of the S. meliloti bdhA mutant complementing clones restored d-3-hydroxybutyrate dehydrogenase activity to the mutant host, for some of the clones this activity was not detectable. This was also the case for almost all of the clones isolated in the E. coli selection. Further analysis was carried out on clones isolated in the S. meliloti complementation. Transposon mutagenesis to locate the complementing genes, followed by DNA sequence analysis of three of the genes, revealed coding sequences that were broadly divergent but lay within the diversity of known short-chain dehydrogenase/reductase encoding genes. In some cases, the amino acid sequence identity between pairs of deduced BdhA proteins was <35%, a level at which detection by nucleic acid hybridization based methods would probably not be successful.

scholarly journals Resistance to Linezolid Caused by Modifications at Its Binding Site on the Ribosome

2011 ◽  
Vol 56 (2) ◽  
pp. 603-612 ◽  
Author(s):  
Katherine S. Long ◽  
Birte Vester
Keyword(s):  
Binding Site ◽  
Ribosomal Proteins ◽  
Resistance Mechanism ◽  
Ribosomal Subunit ◽  
Resistance Mechanisms ◽  
Drug Binding ◽  
23S Rrna ◽  
Detailed Knowledge ◽  
Linezolid Resistance ◽  
Almost All

ABSTRACTLinezolid is an oxazolidinone antibiotic in clinical use for the treatment of serious infections of resistant Gram-positive bacteria. It inhibits protein synthesis by binding to the peptidyl transferase center on the ribosome. Almost all known resistance mechanisms involve small alterations to the linezolid binding site, so this review will therefore focus on the various changes that can adversely affect drug binding and confer resistance. High-resolution structures of linezolid bound to the 50S ribosomal subunit show that it binds in a deep cleft that is surrounded by 23S rRNA nucleotides. Mutation of 23S rRNA has for some time been established as a linezolid resistance mechanism. Although ribosomal proteins L3 and L4 are located further away from the bound drug, mutations in specific regions of these proteins are increasingly being associated with linezolid resistance. However, very little evidence has been presented to confirm this. Furthermore, recent findings on the Cfr methyltransferase underscore the modification of 23S rRNA as a highly effective and transferable form of linezolid resistance. On a positive note, detailed knowledge of the linezolid binding site has facilitated the design of a new generation of oxazolidinones that show improved properties against the known resistance mechanisms.

scholarly journals Effects of the white allele of the mi locus on coat pigmentation in chimeric mice

1994 ◽  
Vol 63 (3) ◽  
pp. 175-181
Author(s):  
Boris V. Konyukhov ◽  
Boris N. Kindyakov ◽  
Natalia A. Malinina
Keyword(s):  
Proliferative Activity ◽  
Coat Color ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Electrophoretic Analysis ◽  
Hair Follicles ◽  
Pigment Cells ◽  
Color Patterns ◽  
Proliferation And Differentiation ◽  
Almost All

SummaryTo investigate the cellular action of the Miωh allele in the mouse with regard to its effects upon coat color patterns, we generated a series of aggregation chimeras, using embryos that differ in their mi locus genotype. We have obtained 11 chimeras Miωh/ + C/C↔ + / + c/c and 8 chimeras + / + C/C↔ + / + c/c. Chimerism was determined by coat and retinal pigment epithelium mosaicism and by the electrophoretic analysis of GPI-1 isoenzymes. In Miωh/+ C/C↔, +/+ c/c mice white coat color prevailed due to the higher percentage of unpigmented areas and the higher percentage of unpigmented hairs in pigmented areas. Our data indicate that a single Miωh gene dose decreases the melanoblast proliferative activity, causing the lightening of coat pigmentation. In Miωh/ + C/C↔+/+ c/c mice a few pigmented hairs were often detected on the belly where Miωh / + mice always had a white spot. This suggests that in the chimeras the presence of some non-Miωh cells in the skin of the belly allows pigment cells to develop. Using embryos of two substrains of Miωh/Miωh mice that differ in their Gpi-1 locus genotype we have produced 8 Miωh/ + ↔ Miωh/Miωh chimeras. In all these chimeras coat color patterns resembled those of Miωh/ + heterozygotes despite the higher percentage of the Miwh/Miωh component in three chimeras. Mosaic hairs were absent in the chimeras. This shows that the chimeras have only one Miωh/ + melanoblast population which actively proliferates and colonizes almost all hair follicles. Thus the Miωh/Miωh dermis and epidermis do not suppress proliferation and differentiation of the Miωh/ + melanoblasts except the certain area on the belly.

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