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941.
Mozammel Hoque Daniel J. Shea Mitsuru Asada Md. Asad-ud-doullah Motoki Shimizu Ryo Fujimoto Eigo Fukai Keiichi Okazaki 《Molecular breeding : new strategies in plant improvement》2017,37(9):109
The tuberous stem of kohlrabi is an important quantitative trait, which affects its yield and quality. Genetic control of this trait has not yet been unveiled. To identify the QTLs controlling stem swelling of kohlrabi, a BC1 population of 92 plants was developed from a cross of broccoli DH line GCP04 and kohlrabi var. Seine. A wide range of variation in tuberous stem diameter was observed among the mapping populations. We constructed a genetic map of nine linkage groups (LGs) with different types of markers, spanning a total length of 913.5 cM with an average marker distance of 7.55 cM. Four significant QTLs for radial enlargement of kohlrabi stem, namely, REnBo1, REnBo2, REnBo3, and REnBo4 were detected on C02, C03, C05, and C09, respectively, and accounted for the phenotypic variation of 59% for the stem diameter and 55% for the qualitative grading of tuberous stem in classes. Then, we confirmed the stability of identified QTLs using BC1S1 populations derived from the BC1 plants having heterozygous alleles at the target QTL and homozygous kohlrabi alleles at the remaining QTLs. REnBo1and REnBo2 using 128 plants of BC168S1 and 94 plants of BC143S1, respectively, and REnBo3 and REnBo4 using 152 plants of BC157S1 were detected at the same positions as the respective QTLs of the BC1 population. Confirmation of QTLs in two successive generations indicates that the QTLs are persistent. The QTLs obtained in this study could be useful in marker-assisted selection of kohlrabi breeding, and to understand the genetic mechanisms of stem swelling and storage organ development in kohlrabi and other Brassica species. 相似文献
942.
943.
944.
Ernesto Shimizu Analía Macías Fernando Paolicchi Gabriel Magnano Laura Zapata Analía Fernández Ana Canal Sergio Garbaccio Angel Cataldi Karina Caimi Martín Zumárraga 《Memórias do Instituto Oswaldo Cruz》2014,109(2):236-245
Mycobacterium bovis is the causative agent of bovine tuberculosis
(TB), a disease that affects approximately 5% of Argentinean cattle. Among the
molecular methods for genotyping, the most convenient are spoligotyping and variable
number of tandem repeats (VNTR). A total of 378 samples from bovines with visible
lesions consistent with TB were collected at slaughterhouses in three provinces,
yielding 265 M. bovis spoligotyped isolates, which were distributed
into 35 spoligotypes. In addition, 197 isolates were also typed by the VNTR method
and 54 combined VNTR types were detected. There were 24 clusters and 27 orphan types.
When both typing methods were combined, 98 spoligotypes and VNTR types were observed
with 27 clusters and 71 orphan types. By performing a meta-analysis with previous
spoligotyping results, we identified regional and temporal trends in the population
structure of M. bovis. For SB0140, the most predominant spoligotype
in Argentina, the prevalence percentage remained high during different periods,
varying from 25.5-57.8% (1994-2011). By contrast, the second and third most prevalent
spoligotypes exhibited important fluctuations. This study shows that there has been
an expansion in ancestral lineages as demonstrated by spoligotyping. However, exact
tandem repeat typing suggests dynamic changes in the clonal population of this
microorganism. 相似文献
945.
946.
Ono E Inoue J Hashidume T Shimizu M Sato R 《Biochemical and biophysical research communications》2011,(3):677-681
TGR5 is a member of the G protein-coupled receptor family and is activated by bile acids (BAs). TGR5 is thought to be a promising drug target for metabolic diseases because the activation of TGR5 prevents obesity and hyperglycemia in mice fed a high-fat diet (HFD). In the present study, we identified a naturally occurring limonoid, nomilin, as an activator of TGR5. Unlike BAs, nomilin did not exhibit the farnesoid X receptor ligand activity. Although the nomilin derivative obacunone was capable of activating TGR5, limonin (the most abundant limonoid in citrus seeds) was not a TGR5 activator. When male C57BL/6J mice fed a HFD for 9 weeks were further fed a HFD either alone or supplemented with 0.2% w/w nomilin for 77 days, nomilin-treated mice had lower body weight, serum glucose, serum insulin, and enhanced glucose tolerance. Our results suggest a novel biological function of nomilin as an agent having anti-obesity and anti-hyperglycemic effects that are likely to be mediated through the activation of TGR5. 相似文献
947.
948.
Saito F Saito-Arai Y Nakamura-Okuma A Ikeda M Hagiwara H Masaki T Shimizu T Matsumura K 《Biochemical and biophysical research communications》2011,(2):494-369
α-Dystroglycan (α-DG) plays crucial roles in maintaining the stability of cells. We demonstrated previously that the N-terminal domain of α-DG (α-DG-N) is secreted by cultured cells into the culture medium. In the present study, to clarify its function in vivo, we generated a monoclonal antibody against α-DG-N and investigated the secretion of α-DG-N in human cerebrospinal fluid (CSF). Interestingly, we found that a considerable amount of α-DG-N was present in CSF. α-DG-N in CSF was a sialylated glycoprotein with both N- and O-linked glycan. These observations suggest that secreted α-DG-N may be transported via CSF and have yet unidentified effects on the nervous system. 相似文献
949.
950.
Murakami K Murata N Noda Y Tahara S Kaneko T Kinoshita N Hatsuta H Murayama S Barnham KJ Irie K Shirasawa T Shimizu T 《The Journal of biological chemistry》2011,286(52):44557-44568
Oxidative stress is closely linked to the pathogenesis of neurodegeneration. Soluble amyloid β (Aβ) oligomers cause cognitive impairment and synaptic dysfunction in Alzheimer disease (AD). However, the relationship between oligomers, oxidative stress, and their localization during disease progression is uncertain. Our previous study demonstrated that mice deficient in cytoplasmic copper/zinc superoxide dismutase (CuZn-SOD, SOD1) have features of drusen formation, a hallmark of age-related macular degeneration (Imamura, Y., Noda, S., Hashizume, K., Shinoda, K., Yamaguchi, M., Uchiyama, S., Shimizu, T., Mizushima, Y., Shirasawa, T., and Tsubota, K. (2006) Proc. Natl. Acad. Sci. U.S.A. 103, 11282-11287). Amyloid assembly has been implicated as a common mechanism of plaque and drusen formation. Here, we show that Sod1 deficiency in an amyloid precursor protein-overexpressing mouse model (AD mouse, Tg2576) accelerated Aβ oligomerization and memory impairment as compared with control AD mouse and that these phenomena were basically mediated by oxidative damage. The increased plaque and neuronal inflammation were accompanied by the generation of N(ε)-carboxymethyl lysine in advanced glycation end products, a rapid marker of oxidative damage, induced by Sod1 gene-dependent reduction. The Sod1 deletion also caused Tau phosphorylation and the lower levels of synaptophysin. Furthermore, the levels of SOD1 were significantly decreased in human AD patients rather than non-AD age-matched individuals, but mitochondrial SOD (Mn-SOD, SOD2) and extracellular SOD (CuZn-SOD, SOD3) were not. These findings suggest that cytoplasmic superoxide radical plays a critical role in the pathogenesis of AD. Activation of Sod1 may be a therapeutic strategy for the inhibition of AD progression. 相似文献