scholarly journals Characterization of the gene and mRNA of the large subunit of ribulose-1,5-bisphosphate carboxylase in pea plants.

1983 ◽  
Vol 3 (4) ◽  
pp. 587-595 ◽  
Author(s):  
K K Oishi ◽  
K K Tewari

mRNA coding for the large subunit (LS) of ribulose-1,5-bisphosphate carboxylase was obtained by fractionating chloroplast polysomes on an affinity column, using anti-ribulose-1,5-bisphosphate carboxylase immunoglobulin G. Approximately 20% of the polysomal RNA specifically bound to the affinity column. LS mRNA was also isolated by fractionating chloroplast polysomal RNA on sucrose gradients. The LS mRNA fraction was identified by translation in vitro followed by immunoprecipitation with anti-ribulose-1,5-bisphosphate carboxylase immunoglobulin G. Labeled LS mRNA was hybridized to a genomic digests of pea chloroplast DNA. The LS gene was localized on a 3.55-kilobase pair BamHI fragment in SalI-SmaI DNA fragment 4. The BamHI fragment containing the LS gene was cloned, and a restriction endonuclease map was constructed. The LS gene was localized on a 1.9-kbp KpnI-EcoRI fragment. The LS gene was analyzed by electron microscopy, using the R loop mapping technique. LS mRNA was colinear with the gene, and its size was 1.35 +/- 0.2 kilobase pairs. When the LS mRNA was analyzed on methylmercury agarose gels, it comigrated with the 16S rRNA. The direction of transcription of the LS gene was in the same direction as that of the rRNA genes.

1983 ◽  
Vol 3 (4) ◽  
pp. 587-595
Author(s):  
K K Oishi ◽  
K K Tewari

mRNA coding for the large subunit (LS) of ribulose-1,5-bisphosphate carboxylase was obtained by fractionating chloroplast polysomes on an affinity column, using anti-ribulose-1,5-bisphosphate carboxylase immunoglobulin G. Approximately 20% of the polysomal RNA specifically bound to the affinity column. LS mRNA was also isolated by fractionating chloroplast polysomal RNA on sucrose gradients. The LS mRNA fraction was identified by translation in vitro followed by immunoprecipitation with anti-ribulose-1,5-bisphosphate carboxylase immunoglobulin G. Labeled LS mRNA was hybridized to a genomic digests of pea chloroplast DNA. The LS gene was localized on a 3.55-kilobase pair BamHI fragment in SalI-SmaI DNA fragment 4. The BamHI fragment containing the LS gene was cloned, and a restriction endonuclease map was constructed. The LS gene was localized on a 1.9-kbp KpnI-EcoRI fragment. The LS gene was analyzed by electron microscopy, using the R loop mapping technique. LS mRNA was colinear with the gene, and its size was 1.35 +/- 0.2 kilobase pairs. When the LS mRNA was analyzed on methylmercury agarose gels, it comigrated with the 16S rRNA. The direction of transcription of the LS gene was in the same direction as that of the rRNA genes.


Parasitology ◽  
1999 ◽  
Vol 118 (6) ◽  
pp. 541-551 ◽  
Author(s):  
N. E. COLLINS ◽  
B. A. ALLSOPP

We sequenced the rRNA genes and internal transcribed spacers (ITS) of several Theileria parva isolates in an attempt to distinguish between the causative agents of East coast fever and Corridor disease. The small subunit (SSU) and large subunit (LSU) rRNA genes from a cloned T. p. lawrencei parasite were sequenced; the former was identical to that of T. p. parva Muguga, and there were minor heterogeneities in the latter. The 5·8S gene sequences of 11 T. parva isolates were identical, but major differences were found in the ITS. Six characterization oligonucleotides were designed to hybridize within the variable ITS1 region; 93·5% of T. p. parva isolates examined were detected by probe TPP1 and 81·8% of T. p. lawrencei isolates were detected by TPL2 and/or TPL3a. There was no absolute distinction between T. p. parva and T. p. lawrencei and the former hybridized with fewer of the probes than did the latter. It therefore seems that a relatively homogenous subpopulation of T. parva has been selected in cattle from a more diverse gene pool in buffalo. The ITSs of both T. p. parva and T. p. lawrencei contained different combinations of identifiable sequence segments, resulting in a mosaic of segments in any one isolate, suggesting that the two populations undergo genetic recombination and that their gene pools are not completely separate.


2021 ◽  
Author(s):  
Zenita Adhireksan ◽  
Deepti Sharma ◽  
Phoi Leng Lee ◽  
Qiuye Bao ◽  
Sivaraman Padavattan ◽  
...  

Abstract Structural characterization of chromatin is challenging due to conformational and compositional heterogeneity in vivo and dynamic properties that limit achievable resolution in vitro. Although the maximum resolution for solving structures of large macromolecular assemblies by electron microscopy has recently undergone profound increases, X-ray crystallographic approaches may still offer advantages for certain systems. One such system is compact chromatin, wherein the crystalline state recapitulates the crowded molecular environment within the nucleus. Here we show that nucleosomal constructs with cohesive-ended DNA can be designed that assemble into different types of circular configurations or continuous fibers extending throughout crystals. We demonstrate the utility of the method for characterizing nucleosome compaction and linker histone binding at near-atomic resolution but also advance its application for tackling further problems in chromatin structural biology and for generating novel types of DNA nanostructures. We provide a library of cohesive-ended DNA fragment expression constructs and a strategy for engineering DNA-based nanomaterials with a seemingly vast potential variety of architectures and histone chemistries.


Parasitology ◽  
2004 ◽  
Vol 130 (2) ◽  
pp. 157-167 ◽  
Author(s):  
H. SATO ◽  
A. OSANAI ◽  
H. KAMIYA ◽  
Y. OBARA ◽  
W. JIANG ◽  
...  

Trypanosoma (Herpetosoma) grosi, which naturally parasitizesApodemusspp., can experimentally infect Mongolian jirds (Meriones unguiculatus). Three isolates fromA. agrarius,A. peninsulae, andA. speciosus(named SESUJI, HANTO, and AKHA isolates, respectively) of different geographical origin (AKHA from Japan, and the others from Vladivostok), exhibited different durations of parasitaemia in laboratory jirds (2 weeks for HANTO, and 3 weeks for the others). To assess the genetic background of theseT. grosiisolates, their small (SSU) and large subunit (LSU) ribosomal RNA genes (rDNA) were sequenced along with those of 2 otherHerpetosomaspecies from squirrels. The SSU rDNA sequences of these 3 species along with available sequences of 3 otherHerpetosomatrypanosomes (T. lewisi,T. musculiandT. microti)seemed to reflect well the phylogenetic relationship of their hosts. Three isolates ofT. grosiexhibited base changes at 2–6 positions of 2019-base 18S rDNA, at 5–29 positions of 1817/1818-base 28Sα rDNA, or 1–5 positions of 1557–1559-base 28Sβ rDNA, and none was separated from the other 2 isolates by rDNA nucleotide sequences. Since base changes ofHerpetosomatrypanosomes at the level of inter- and intra-species might occur frequently in specified rDNA regions, the molecular analysis on these regions of rodent trypanosomes could help species/strain differentiation and systematic revision ofHerpetosomatrypanosome species, which must be more abundant than presently known.


1985 ◽  
Vol 5 (10) ◽  
pp. 2733-2745 ◽  
Author(s):  
L Hanley-Bowdoin ◽  
E M Orozco ◽  
N H Chua

The large subunit gene (rbcL) of ribulose 1,5-bisphosphate carboxylase was transcribed in vitro by using maize and pea chloroplast extracts and a cloned plastid DNA template containing 172 base pairs (bp) of the maize rbcL protein-coding region and 791 bp of upstream sequences. Three major in vitro RNA species were synthesized which correspond to in vivo maize rbcL RNAs with 5' termini positioned 300, 100 to 105, and 63 nucleotides upstream of the protein-coding region. A deletion of 109 bp, including the "-300" 5' end (the 5' end at position -300), depressed all rbcL transcription in vitro. A plasmid DNA containing this 109-bp fragment was sufficient to direct correct transcription initiation in vitro. A cloned template, containing 191 bp of plastid DNA which includes the -105 and -63 rbcL termini, did not support transcription in vitro. Exogenously added -300 RNA could be converted to the -63 transcript by maize chloroplast extract. These results established that the -300 RNA is the primary maize rbcL transcript, the -63 RNA is a processed form of the -300 transcript, and synthesis of the -105 RNA is dependent on the -300 region. The promoter for the maize rbcL gene is located within the 109 bp flanking the -300 site. Mutagenesis of the 109-bp chloroplast sequence 11 bp upstream of the -300 transcription initiation site reduced rbcL promoter activity in vitro.


2001 ◽  
Vol 47 (7) ◽  
pp. 626-633 ◽  
Author(s):  
A L Molan ◽  
G T Attwood ◽  
B R Min ◽  
W C McNabb

Five strains of proteolytic rumen bacteria were treated with condensed tannins (CT) purified from Lotus pedunculatus and Lotus corniculatus to investigate their effect on the growth of these bacteria in vitro. Streptococcus bovis NCFB 2476, Eubacterium sp. C124b, Prevotella bryantii B14, Butyrivibrio fibrisolvens H17c, and Clostridium proteoclasticum B316Twere tested against 200, 400, and 600 µg CT·mL–1extracted from L. pedunculatus and L. corniculatus. In the absence of CT, all bacterial strains showed typical growth and reached maximum optical density (OD) after 6–8 h of incubation in a plant protein medium. Growth of Eubacterium sp., P. bryantii, and B. fibrisolvens was inhibited (P < 0.01–0.001) more by the CT from L. pedunculatus than by the CT from L. corniculatus. All strains continued to grow in the presence of 200 µg·mL–1of the CT from L. pedunculatus, but attained significantly (P < 0.05–0.01) lower maximum OD600values than (minus CT) controls, except for S. bovis. At 400 and 600 µg·mL–1, the addition of CT from L. pedunculatus inhibited (P < 0.05–0.001) the growth of all bacterial strains tested compared with controls. The growth of Eubacterium sp. and P. bryantii was stimulated for the first 4–6 h of incubation (P < 0.001) by 200 µg·mL–1of CT from L. corniculatus, but then declined leading to a significant difference in OD values compared with the controls. At 400 µg·mL–1, the CT from L. corniculatus reduced (P < 0.05–0.01) the growth of all strains except S. bovis, while 600 µg·mL–1inhibited (P < 0.01–0.001) the growth of all strains. To study the mechanism of CT action, the degradation of the large subunit (LSU) of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco; Fraction 1 Leaf protein) was followed after bacterial cells or Rubisco were preincubated with CT extracted from L. corniculatus and L. pedunculatus. Both preincubations decreased LSU degradation, but they differed in their response to polyethylene glycol (PEG) addition. Addition of PEG to CT–Rubisco preincubations negated the effects of CT, while PEG addition to CT–bacteria preincubations did not. This implies that the CT–bacterial interaction is stronger than the CT–Rubisco interaction or the interaction is of a different type. Also, L. pedunculatus CT reduced the degradation of the LSU to a greater extent than the CT from L. corniculatus when preincubated with bacteria.Key words: condensed tannins, growth, in vitro, proteolytic rumen bacteria, mode of action, Rubisco.


2009 ◽  
Vol 47 (6) ◽  
pp. 609-617 ◽  
Author(s):  
Colin J. Jackson ◽  
Richard C. Barton ◽  
C. Graham Clark ◽  
Steven L. Kelly

1986 ◽  
Vol 103 (4) ◽  
pp. 1327-1335 ◽  
Author(s):  
S Cannon ◽  
P Wang ◽  
H Roy

We have developed an assay to monitor in vitro the posttranslational assembly of the chloroplast protein, ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO). Most of the newly synthesized 55-kD catalytic ("large") subunits of this enzyme occur in a 29S complex together with 60- and 61-kD "binding" proteins. When the 29S complex is incubated with ATP and MgCl2 it dissociates into subunits, and the formerly bound large subunits now sediment at 7S (still faster than expected for a monomer). Upon incubation at 24 degrees C, these large subunits assemble into RuBisCO. The minority of newly made large subunits which are not bound to the 29S complex also sediment at 7S. When endogenous ATP was removed by addition of hexokinase and glucose, the dissociation of the 29S complex was inhibited. Nevertheless, the 7S large subunits assembled into RuBisCO, and did so to a greater extent than in controls retaining endogenous ATP. Thus the 7S large subunits are also assembly competent, at least when ATP is removed. Apparently, in chloroplast extracts, ATP can have a dual effect on the assembly of RuBisCO: on the one hand, even at low concentrations it can inhibit incorporation of 7S large subunits RuBisCO; on the other hand, at higher concentrations it can lead to substantial buildup of the 7S large subunit pool by causing dissociation of the 29S complex, and stimulate overall assembly. At both high and zero concentrations of ATP, however, antibody to the binding protein inhibited the assembly of endogenous large subunits into RuBisCO. Thus it appears that all assembly-competent large subunits are associated with the binding protein, either in the 7S complex or in the 29S complex. The involvement of the binding protein in RuBisCO assembly may represent the first example of non-autonomous protein assembly in higher plants and may pose problems for the genetic engineering of RuBisCO from these organisms.


2021 ◽  
Vol 9 (8) ◽  
pp. 809
Author(s):  
Meng-Chou Lee ◽  
Han-Yang Yeh

The genus Colaconema, containing endophytic algae associated with economically important macroalgae, is common around the world, but has rarely been reported in Taiwan. A new species, C. formosanum, was found attached to an economically important local macroalga, Sarcodia suae, in southern Taiwan. The new species was confirmed based on morphological observations and molecular analysis. Both the large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (rbcL) and cytochrome c oxidase subunit I (COI-5P) genes showed high genetic variation between our sample and related species. Anatomical observations indicated that the new species presents asexual reproduction by monospores, cylindrical cells, irregularly branched filaments, a single pyrenoid, and single parietal plastids. Our research supports the taxonomic placement of C. formosanum within the genus Colaconema. This study presents the third record of the Colaconema genus in Taiwan.


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