5 research outputs found
New allele of HvBRI1 gene encoding brassinosteroid receptor in barley
The aim of these studies was to characterize
nucleotide substitutions leading to the phenotype of
brassinosteroid-insensitive, semi-dwarf barley mutant
093AR. Two substitutions in the sequence of barley HvBRI1
gene, encoding leucine-rich repeats receptor kinase (LRRRK),
which participates in brassinosteroid (BR) signalling,
were identified in this chemically-induced barley mutant of
the cv. Aramir. The LRR-RK is a transmembrane protein
phosphorylating downstream components. The identified
substitutions CC>AA at positions 1760 and 1761 in the
HvBRI1 gene of this mutant led to a missense mutation,
causing the Thr-573 to Lys-573 replacement in the protein
sequence. The threonine residue is situated in the distal part
of a 70-amino acids island responsible for binding of BR
molecules. As this residue is conserved among BRI1
protein homologs in Arabidopsis thaliana, Lycopersicon
esculentum, Oryza sativa and Hordeum vulgare, it was
postulated that this residue is crucial for the protein
function. The genetic analyses indicated that the mutant
093AR was allelic to the spontaneous, semi-dwarf mutant
uzu which carries A>G substitution at position 2612 of the
HvBRI1 gene (GenBank acc. no. AB088206). A comparison
of the genomic sequence of HvBRI1 in the mutants uzu,
093AR and in the cv. âAramirâ confirmed the presence of
the single-nucleotide A>G substitution at position 2612 in
the sequence encoding kinase domain of HvBRI1 polypeptide
in uzu, but not in 093AR mutant, indicating that a new
allele of the HvBRI1 gene was identified
Identification of barley DWARF gene involved in brassinosteroid synthesis
Brassinosteroids (BR) are plant steroid hormones
regulating various aspects of morphogenesis, such
as seed development and germination, cell division and
elongation, differentiation of tracheary elements, development
during growth in darkness (skotomorphogenesis),
photosynthesis and response to environmental stress.
Brassinosteroid synthesis has been studied to a great extent
in the dicot species, Arabidopsis thaliana, resulting in the
identification of genes participating in this process. Much
less is known about BR synthesis in crops, including the
monocots. The purpose of this study was to identify and
characterize barley coding sequence HvDWARF involved
in brassinosteroid synthesis. This sequence, encoding
brassinosteroid-6-oxidase, was identified on the basis of
barley ESTs. This sequence was screened for nucleotide
substitutions in semi-dwarf, chemically-induced barley
mutants exhibiting changes in etiolation. The responsiveness
of these genotypes to exogenous brassinosteroids was
determined with the use of leaf-blade segment unrolling
tests. The semi-dwarf phenotype of the BR-deficient
mutants was rescued by the application of 10-5 M 24-epibrassinolide.
Two missense mutations were identified
within the HvDWARF sequence in BR-deficient mutants
522DK and 527DK from variety âDelisaâ. These substitutions
cause changes of amino acid residues located within
the conserved fragments of the encoded polypeptide. Thetranscription profile of HvDWARF and HvBAK1/SERK3,
involved in BR signaling, was determined during the early
stages of seedling development in BR-deficient and BRinsensitive
mutants using real-time quantitative PCR. This
analysis indicated that HvDWARF displays a uniformly
low level of this process, whereas the transcription level of
HvBAK1 proved to be spatially and temporally regulated
Evaluation of Orofacial and General Pain Location in Patients With Temporomandibular Joint DisorderâMyofascial Pain With Referral
Introduction: Pain is an emotional experience. As a subjective feeling, it is associated with pathophysiological processes occurring in the central nervous system, which in turn may negatively affect the psychophysical function, cognitive abilities, level of functioning and quality of life.The Aim: The aim of the study was to assess orofacial and general pain location in patients with temporomandibular joint disorderâmyofascial pain with referral.Materials and Methods: The study group consisted of 50 randomly selected, generally healthy people with complete natural dentition (37 women and 13 men) at the age of 23.36 ± 2.14 years, referred to the Department of Prosthodontics of the Medical University. All patients underwent clinical examination according to the Diagnostic Criteria for Temporomandibular Disorders (Axes I and II). The subjects were classified as people with myofascial pain with referral. The evaluation of severity of temporomandibular disorders was based on the Temporomandibular Disorder Pain Screener and the Graded Chronic Pain Scale. In order to assess orofacial and general pain location, a bodychart drawing of pain was used.Results: The study group indicated 40 different areas of the body affected by pain. 2â3 isolated pain locations were declared by a total of six subjects. One person identified 17 affected areas. Forty four people reported pain in at least four regions of the body. 70% of patients suffered from pain within the right masseter muscle. Pain of the left masseter muscle was noted in 68% of cases. Cervical ailments were reported by 56% of people. Pain of the left temporomandibular joint was observed in 68% of patients, and of the right one in 54%.Conclusion: The patients with myofascial pain with referral suffer from general ailments in different regions of the body. Only the frequency of pain in the right masseter muscle and right temporomandibular joint differed with respect to gender. The suggestion that the prevalence of pain in other areas of the body varies between men and women has not been confirmed. Due to a small sample size, such differences cannot be excluded. Further studies in this area are needed
Instrument-model refinement in normalized reciprocal-vector space for X-ray Laue diffraction
A simple yet efficient instrument-model refinement method for X-ray diffraction data is presented and discussed. The method is based on least-squares minimization of differences between respective normalized (i.e. unit length) reciprocal vectors computed for adjacent frames. The approach was primarily designed to work with synchrotron X-ray Laue diffraction data collected for small-molecule single-crystal samples. The method has been shown to work well on both simulated and experimental data. Tests performed on simulated data sets for small-molecule and protein crystals confirmed the validity of the proposed instrument-model refinement approach. Finally, examination of data sets collected at both BioCARS 14-ID-B (Advanced Photon Source) and ID09 (European Synchrotron Radiation Facility) beamlines indicated that the approach is capable of retrieving goniometer parameters (e.g. detector distance or primary X-ray beam centre) reliably, even when their initial estimates are rather inaccurate.
Keywords: data processing; Laue diffraction; instrument models; refinement; X-ray diffraction
On the Nature of Luminescence Thermochromism of Multinuclear Copper(I) Benzoate Complexes in the Crystalline State
A model luminescent [(PhCO2)4Cu4] (Cu4) complex in the crystalline state was investigated via combined crystallographic and spectroscopic techniques contributed substantially by theoretical modelling. The complex appeared to exhibit luminescence thermochromism, i.e., red phosphorescence at room temperature which changes to green when lowering the temperature to 90 K. The low-energy emissive state was assigned as a cluster-centred triplet, 3CC. The emission from this state predicted in TDDFT (~635 nm) matches the experimental red band observed at 660–715 nm. In contrast, the nature of the high-energy “green” band was less straightforward. The next reached cluster-centred triplet excited state occurred to be energetically close to the experimental value of ~545 nm. The two excited states also exhibit significant metal-to-ligand and ligand-to-metal charge transfer characteristics, especially for solid-state distorted geometries. In both cases the cluster core was expected to become notably contracted when compared to the ground state. Time-resolved photocrystallographic results supported the computationally predicted core contraction upon excitation. Additionally, the differences between the spectroscopic behaviour of the related tetra- and hexanuclear copper(I) complexes, Cu4 and Cu6 (i.e., [(PhCO2)6Cu6]) in the crystalline state were discussed and examined. It appeared that crystal packing may constitute an important factor as far as the lack of luminescence thermochromism in the latter case is concerned. Synopsis: Structure–property relationships characterising a model luminescent [(PhCO2)4Cu4] (Cu4) complex in the crystalline state were investigated via combined crystallographic and spectroscopic techniques contributed by theoretical modelling, and compared with the properties of the related [(PhCO2)6Cu6] (Cu6) complex