2,143 research outputs found
Sow Thistle Chloroplast Genomes: Insights into the Plastome Evolution and Relationship of Two Weedy Species, Sonchus asper and Sonchus oleraceus (Asteraceae)
Prickly sow thistle, Sonchus asper (L.) Hill, and common sow thistle, Sonchus oleraceus L., are
noxious weeds. Probably originating from the Mediterranean region, they have become widespread
species. They share similar morphology and are closely related. However, they differ in their
chromosome numbers and the precise relationship between them remains uncertain. Understanding
their chloroplast genome structure and evolution is an important initial step toward determining
their phylogenetic relationships and analyzing accelerating plant invasion processes on a global scale.
We assembled four accessions of chloroplast genomes (two S. asper and two S. oleraceus) by the next
generation sequencing approach and conducted comparative genomic analyses. All the chloroplast
genomes were highly conserved. Their sizes ranged from 151,808 to 151,849 bp, containing 130 genes
including 87 coding genes, 6 rRNA genes, and 37 tRNA genes. Phylogenetic analysis based on the
whole chloroplast genome sequences showed that S. asper shares a recent common ancestor with
S. oleraceus and suggested its likely involvement in a possible amphidiploid origin of S. oleraceus.
In total, 79 simple sequence repeats and highly variable regions were identified as the potential
chloroplast markers to determine genetic variation and colonization patterns of Sonchus species
Phylogenomic insight into dysploidy, speciation, and plastome evolution of a small Mediterranean genus Reichardia (Cichorieae; Asteraceae)
Reichardia Roth is a small Mediterranean genus comprising ten homogeneous species with basic
chromosome numbers of 7, 8, and 9. To assess the plastid genome evolution and diferentiation of
Reichardia species, we assembled the complete plastome sequences of seven Reichardia and two
Launaea species and conducted various phylogenomic analyses comparatively with nuclear ribosomal
DNA ITS sequences. Reichardia and Launaea plastomes were highly conserved in gene content and
order, containing 130 genes. Plastid phylogenomic reconstruction strongly suggested that Reichardia
was a sister to Launaea, and its common ancestor initially diverged into two major lineages: the
frst containing species with n= 8 chromosomes exclusively, and the other with n= 9, 8, and 7
chromosomes. Although the ancestral Reichardia karyotype was suggested to most likely be n= 9 from
ancestral chromosome number reconstruction, the pattern of descending dysploidy indicated by the
phylogenetic trees based on nuclear ribosomal DNA ITS was less evident in the trees based on the
plastome. Possible reasons for these fndings are discussed
Evidence for the Existence of Secretory Granule (Dense-Core Vesicle)-Based Inositol 1,4,5-Trisphosphate-Dependent Ca2+ Signaling System in Astrocytes
BACKGROUND: The gliotransmitters released from astrocytes are deemed to play key roles in the glial cell-neuron communication for normal function of the brain. The gliotransmitters, such as glutamate, ATP, D-serine, neuropeptide Y, are stored in vesicles of astrocytes and secreted following the inositol 1,4,5-trisphosphate (IP3)-induced intracellular Ca2+ releases. Yet studies on the identity of the IP3-dependent intracellular Ca2+ stores remain virtually unexplored. PRINCIPAL FINDINGS: We have therefore studied the potential existence of the IP3-sensitive intracellular Ca2+ stores in the cytoplasm of astrocytes using human brain tissue samples in contrast to cultured astrocytes that had primarily been used in the past. It was thus found that secretory granule marker proteins chromogranins and secretogranin II localize in the large dense core vesicles of astrocytes, thereby confirming the large dense core vesicles as bona fide secretory granules. Moreover, consistent with the major IP3-dependent intracellular Ca2+ store role of secretory granules in secretory cells, secretory granules of astrocytes also contained all three (types 1, 2, and 3) IP3R isoforms. SIGNIFICANCE: Given that the secretory granule marker proteins chromogranins and secretogranin II are high-capacity, low-affinity Ca2+ storage proteins and chromogranins interact with the IP3Rs to activate the IP3R/Ca2+ channels, i.e., increase both the mean open time and the open probability of the channels, these results imply that secretory granules of astrocytes function as the IP3-sensitive intracellular Ca2+ store
Free Hand Pedicle Screw Placement in the Thoracic Spine without Any Radiographic Guidance : Technical Note, a Cadaveric Study
Thoracic pedicle screw fixation techniques are still controversial for thoracic deformities because of possible complications including neurologic deficit. Methods to aid the surgeon in appropriate screw placement have included the use of intraoperative fluoroscopy and/or radiography as well as image-guided techniques. We describe our technique for free hand pedicle screw placement in the thoracic spine without any radiographic guidance and present the results of pedicle screw placement analyzed by computed tomographic scan in two human cadavers. This free hand technique of thoracic pedicle screw placement performed in a step-wise, consistent, and compulsive manner is an accurate, reliable, and safe method of insertion to treat a variety of spinal disorders, including spinal deformity
Synergistic effect of Indium and Gallium co-doping on growth behavior and physical properties of hydrothermally grown ZnO nanorods
We synthesized ZnO nanorods (NRs) using simple hydrothermal method, with the simultaneous incorporation of gallium (Ga) and indium (In), in addition, investigated the co-doping effect on the morphology, microstructure, electronic structure, and electrical/optical properties. The growth behavior of the doped NRs was affected by the nuclei density and polarity of the (001) plane. The c-axis parameter of the co-doped NRs was similar to that of undoped NRs due to the compensated lattice distortion caused by the presence of dopants that are both larger (In3+) and smaller (Ga3+) than the host Zn2+ cations. Red shifts in the ultraviolet emission peaks were observed in all doped NRs, owing to the combined effects of NR size, band gap renormalization, and the presence of stacking faults created by the dopant-induced lattice distortions. In addition, the NR/p-GaN diodes using co-doped NRs exhibited superior electrical conductivity compared to the other specimens due to the increase in the charge carrier density of NRs and the relatively large effective contact area of (001) planes. The simultaneous doping of In and Ga is therefore anticipated to provide a broader range of optical, physical, and electrical properties of ZnO NRs for a variety of opto-electronic applications
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