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A B Legocki

Publications and source records attributed to A B Legocki.

At least 37 records · Page 2Linked to original sources
PubMed1989

Nodule-specific repression of yellow lupin protein R18.

It was found, using immunochemical techniques, that protein R18 presumably specifically repressed during development of lupin root nodules (Sikorski et al., 1989, Acta Biochim. Polon., 36, 63-72) is present in various tissues of this plant. Protein R18 was also detected in roots of four other legumes but was absent from the bacteroid-containing cells of root nodules. The data support our earlier view (Sikorski et al., op. cit.) that expression of protein R18 is regulated by the coupled mechanism of induction and repression of specific plant genes during development of lupin root nodule.

Fabaceae↗
PubMed1989

Glutamine synthetase in Lupinus luteus. Identification and preliminary characterization of nodule-specific cDNA clone.

Two glutamine synthetase (GS) cDNA clones from L. luteus were identified and characterized. The nucleotide sequence analysis proved that they represent highly homologous but distinct mRNA species. Northern blot hybridization revealed that pc LINGS encodes the nodule-specific subunit of the GS while pcLIGS1 represents the nonspecific one present in nodule tissue as well as in uninfected roots.

Amino Acid Sequence↗
PubMed1989

Coordinated synthesis of leghemoglobin and root protein R18 in yellow lupin.

Uninfected roots of yellow lupin contain an abundant 18 kDa protein (referred to as R18), absent in the mature nodules. Some properties of this polypeptide are apparently similar to those of lupin leghemoglobins. However, the lack of any immuno crossreaction between R18 and leghemoglobin and differences in N-terminal amino acid sequences indicate that these proteins are coded by different genes. The decrease in the content of R18 protein in developing nodule is associated with the increased synthesis of leghemoglobin. This implies coordination of both events.

Amino Acid Sequence↗
PubMed1988

Isolation and characterization of root nodule proteins from lupin.

A group of root nodule-specific plant proteins (nodulins) has been isolated from yellow lupin (Lupinus luteus) by immunoaffinity chromatography. The cytoplasmic nodule protein extract was initially enriched in nodulins on a column with immobilized IgG fraction. It was then purified by chromatography on Sepharose 4B - bound IgG against uninfected root proteins and finally on Sepharose 4B - bound IgG against Rhizobium lupini proteins. Rocket immunoelectrophoresis showed that the nodulin preparation did not react with antibodies against root or bacterial proteins. SDS gel electrophoresis of lupin nodulins revealed at least 23 polypeptides ranging in Mr, from 7,000 to 70,000, probably representing protein subunits.

Animals↗
PubMed1987

Molecular cloning of lupin leghemoglobin cDNA.

Poly(A)+ RNA isolated from root nodules of yellow lupin (Lupinus luteus, var. Ventus) has been used as a template for the construction of a cDNA library. The ds cDNA was synthesized and inserted into the Hind III site of plasmid pBR 322 using synthetic Hind III linkers. Clones containing sequences specific for nodules were selected by differential colony hybridization using 32P-labeled cDNA synthesized either from nodule poly(A)+ RNA or from poly(A)+ RNA of uninfected root as probes. Among the recombinant plasmids, the cDNA gene for leghemoglobin was identified. The protein structure derived from its nucleotide sequence was consistent with known amino acid sequence of lupin Lb II. The cloned lupin Lb cDNA hybridized to poly(A)+ RNA from nodules only, which is in accordance with the general concept, that leghemoglobin is expressed exclusively in nodules.

Amino Acid Sequence↗
PubMed1987

Lupin leghemoglobins during root nodule development.

Two yellow lupin leghemoglobins, Lb I and Lb II, were purified to homogeneity using the HPLC technique for final separation. Lb I and Lb II were identified by the N-terminal sequences and their reaction with antibodies against electrophoretically pure leghemoglobin. The third Lb species was detected by the combined method of isoelectrofocusing and PAGE of Lb I. It seems that Lb III represents a posttranslational modification of Lb I. Developmental changes in Lb multiple forms were examined using the Western blotting method. The content of leghemoglobin, first detectable approximately 3 weeks after infection, increased up to 6-7 weeks, and then it remained at the same level until 8-9 weeks after the infection. At the early stages of nodule formation Lb I prevailed over Lb II, while later Lb II became the predominant form. This suggests physiological role of particular forms and precise regulation of the expression of Lb genes.

Amino Acid Sequence↗
PubMed1987

Cloning and identification of lupin nodule specific cDNA sequences.

Yellow lupin nodule specific sequences were selected by screening of cDNA library prepared from lupin nodule poly(A)+RNA. From about 3,000 clones containing fragments of lupin DNA 150-1,500 base pair long, 7% of clones carrying nodule specific sequences were identified. Among them the most abundant sequence species, represented by 32% clones, encodes leghemoglobin. Another abundant species designated pLN13 is represented by 13% clones. The Northern blot analysis of lupin mRNA confirmed nodule specificity of the cloned sequences. The nucleotide sequence of one clone, pLN281 of 225 bp, is presented.

Base Sequence↗
PubMed1985

Identification and synthesis in vitro of plant-specific proteins in yellow lupin root nodules.

Fifteen to twenty specific polypeptides of Mr ranging from 15 000 to 90 000 were detected using immunochemical techniques in the lupin root nodules and cell-free translation products of the nodule polysomal RNA. These polypeptides were characteristic for symbiotic state of the host plant and represented 9-18% of total nodule proteins. They were absent in uninfected roots and in protein extracts of Rhizobium lupini.

Isoelectric Point↗
PubMed1984

Reverse transcription and kinetic complexity analysis of mRNA from lupin root nodules.

Complementary DNA (cDNA) synthesis was performed using mRNA from lupin root nodules and from lupin uninfected roots as templates. Optimal conditions for the synthesis of 700 nucleotides long cDNA were established. Hybridization kinetics of mRNA-cDNA were performed in a homologous system from root nodules as well as in a heterologous system. Hybridization analysis revealed the presence of four frequency abundance classes within the root nodule mRNA population. In order to enrich the cDNA population in leghaemoglobin sequences, two synthetic pentadecanucleotide fragments complementary to the putative 3' ends of leghaemoglobin mRNAs were used as primers for the reverse transcription of nodule poly(A)-RNA. The resultant cDNA was enriched in rapidly hybridizing components which may contain leghaemoglobin sequences.

Base Sequence↗
PubMed1983

Control of protein synthesis in a wheat germ cell-free system.

Thermostable low molecular weight translational inhibitor was found in wheat germ cell-free extract. The inhibitor was formed during preincubation of wheat S-23 fraction with components of the energy-supplying system (ATP, GTP, phosphoenolpyruvate) in the absence of exogenous mRNA. The inhibitor effectively and irreversibly blocks protein synthesis in both wheat germ and rabbit reticulocyte systems. Our results seem to suggest that the inhibitor can activate wheat endogenous mRNA, which under the standard conditions does not reveal template activity but, once activated, can effectively compete with exogenous mRNA.

Cell-Free System↗
PubMed1981

Cotton messenger RNA sequences exist in both polyadenylated and nonpolyadenylated forms.

The physical characteristics and sequence content of polyadenylated and nonpolyadenylated messenger RNAs were determined in total and polysomal RNAs isolated from cotton cotyledons after 24 h of germination. RNAs were fractionated on the basis of their poly(A) content by passage through poly(U)-agarose. The mass average size of poly(A) is 112 +/- 4 nucleotides in total RNA and 81 +/- 3 nucleotides in polysomal RNA. Less than 2% of the poly(A) tracts are between 5-15 nucleotides in length. The mass average length of recovered polyadenylated mRNAs from either RNA is 1600 nucleotides. In vitro translation of the RNAs in the wheat germ system and hybridization of the RNAs with complementary DNAs confirmed the physical estimates of their absolute amounts. About 3.3% of the high molecular weight RNA in the tissue is mRNA, of which 40% is on polysomes. Abut 45% of the polysomal mRNA and 75% of the nonpolysomal mRNA is polyadenylated. These mRNAs are transcribed from nonrepetitive DNA. Both techniques unambiguously demonstrate that all mRNA populations contain the same sequences in about the same relative concentration. At this point of development in this tissue, differential polyadenylation or entry into polysomes cannot be specific for particular mRNA sequences.

Gossypium↗
PubMed1981

Identification by affinity chromatography of wheat germ ribosomal proteins which interact with RNA.

Wheat germ ribosomal proteins that bind to poly(U), tRNA and poly(A)-containing mRNA for leghaemoglobin were identified by affinity chromatography. The ribosomal proteins that associate with polynucleotides immobilized on Sepharose or on cellulose were identified by polyacrylamide gel electrophoresis. Nine 40S and nine 60S ribosomal proteins were bound to poly(U)-Sepharose. tRNA-Sepharose 4B interacted with five proteins of 40S subunit and with seven proteins of 60S subunit. Six proteins of 60S subunit were bound to poly(A)-containing mRNA for leghaemoglobin. The ribosomal proteins from the small subparticle were not determined because of irreversible binding to the column.

Chromatography, Affinity↗
PubMed1981

Translation and characterization of poly(A)-lacking RNA from lupin root nodules.

Total polysomal RNA from yellow lupin root nodules was fractionated by double oligo(dT)-cellulose chromatography. Poly(A)-containing and poly(A)-lacking RNA fractions showed considerable messenger activity in wheat germ and rabbit reticulocyte cell-free systems. The sizing of poly(A)-lacking RNA on sucrose-density gradient gives rise to separation of 14S mRNA from 22-24S mRNA species. A single polypeptide with molecular weight of 22,000 was coded for by 14S mRNA, while two polypeptides with an apparent mol. wt. of 90,000 and 87,000 were the main products of 22-24S mRNA fraction. High concentrations of unfractionated poly(A)-lacking RNA as well as the addition of poly(A) led to preferential synthesis of the 22,000 product. Preliminary results suggest the presence of m7GpppX cap structure at 5' terminus of the separated 14S and 22-24S mRNA species. This comes from the competition experiments with m7GMP and m7GTP as well as from the fact that the poly(A)-lacking RNA preparation was susceptible to methylation by methyl-transferase from vaccinia virus (methylated is the 2'-O-nucleotide adjacent to 7-methylguanosine). Digestion by T1 RNAase of methylated poly(A)-lacking RNA produced two short 5'-terminal oligonucleotides 10 and 17 nucleotides in length.

Cell-Free System↗
PubMed1981

Translation in vitro of ribonucleic acids from potato virus X, potato virus M and white clover mosaic virus.

Ribonucleic acids from three plant viruses: potato virus X (PVX), potato virus M (PVM) and white clover mosaic virus (WClMV) have been purified and used as messengers in a wheat germ cell-free system. It was demonstrated that each of these viruses contained heavy genomic RNA species of mol. wt. about 2 x 10(6), which appeared to be very efficient templates for protein synthesis in vitro. The synthesis of high-molecular-weight polypeptides: 180 x 10(3), 190 x 10(3) and 170 x 10(3) was directed by PVX, PVM and WClMV RNAs, respectively. None of the polypeptides directed by any of the RNAs studied corresponded to the coat proteins.

Molecular Weight↗