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41.
Masaya Suzuki Kaien Fujino Yumi Nakamoto Masao Ishimoto Hideyuki Funatsuki 《Molecular breeding : new strategies in plant improvement》2010,25(3):407-418
Pod dehiscence (shattering) is a major cause of yield loss in mechanical harvesting of soybeans. To develop useful selection
markers, we conducted a high-resolution mapping of a major quantitative trait locus (QTL) controlling pod dehiscence, designated
as qPDH1. The progeny of a residual heterozygous line, which was a recombinant inbred line segregating only for the genomic region
around qPDH1, was screened for flanking markers to obtain various recombinants in the vicinity of the QTL. Analysis of the relationship
between degree of pod dehiscence and graphical genotype of these lines confined the location of qPDH1 to a 134-kb region on chromosome 16 (formerly linkage group J), where ten putative genes were predicted to be present. None
of these genes showed significant sequence homology with the Arabidopsis genes that have previously been reported to be associated with pod dehiscence, suggesting the presence of a novel gene and
mechanism underlying pod dehiscence in soybean. Sequencing analysis of the parental shattering-resistant and -susceptible
cultivars for the candidate genes revealed a high-frequency nucleotide polymorphism in this genomic region between the cultivars.
Three markers were developed using insertion/deletion variations in the region. Polymorphism at these marker loci was basically
conserved between diverse shattering-resistant and -susceptible cultivars/lines, suggesting the versatility and usefulness
of these markers for marker-assisted selection. 相似文献
42.
Masato Uehara Fumi Kashiwagi Hideyuki Imai Katsunori Tachihara 《Ichthyological Research》2011,58(4):344-349
The age, growth, reproductive condition, and occurrence of natural hybrids of two Nematalosa species around Okinawa Island were examined using 128 specimens obtained from April 2003 to June 2004. Standard length (SL)
reached approximately 150–210 mm within the first 2 years, and then remained stagnant. The maximum age for both sexes was
ca. 5 years old. Maturity sizes and ages were estimated to be at least 173.2 mm SL and 2 years old for females and 192.6 mm
SL and 3 years old for males. Spawnable individuals were mainly observed from January to March based on histological observations
of gonads. Natural hybrids appeared at all sampling sites except for the Haneji Inlet and were dominant at Makiminato (in
south-central Okinawa Island). Their incidence was also quite high (66.9%) in the Makiminato population, when compared with
records for other marine fishes around Japan. In Okinawa Island, these shallow areas are rapidly decreasing in size because
of recent reclamation and land exploitation. Hybrid production may be caused by not only the reproductive biology and sympatric
distributions of the parent species but also recent environmental changes. 相似文献
43.
Fumi Katoh Kazuo Kitamura Hiromi Niina Ryuichi Yamamoto Hisanori Washimine †Kenji Kangawa Yoshitaka Yamamoto Hideyuki Kobayashi Tanenao Eto Akihiko Wada 《Journal of neurochemistry》1995,64(1):459-461
Abstract: In cultured bovine adrenal medullary cells, stimulation of nicotinic receptors by carbachol evoked the Ca2+ -dependent exocytotic cosecretion of proadrenomedullin N-terminal 20 peptide (PAMP) (EC50 = 50.1 µ M ) and catecholamines (EC50 = 63.0 µ M ), with the molar ratio of PAMP/catecholamines secreted being equal to the ratio in the cells. Addition of PAMP[1–20]NH2 inhibited carbachol-induced 22 Na+ influx via nicotinic receptors (IC50 = 2.5 µ M ) in a noncompetitive manner and thereby reduced carbachol-induced 45 Ca2+ influx via voltage-dependent Ca2+ channels (IC50 = 1.0 µ M ) and catecholamine secretion (IC50 = 1.6 µ M ). It did not alter high K+ -induced 45 Ca2+ influx via voltage-dependent Ca2+ channels or veratridine-induced 22 Na+ influx via voltage-dependent Na+ channels. PAMP seems to be a novel antinicotinic peptide cosecreted with catecholamines by a Ca2+ -dependent exocytosis in response to nicotinic receptor stimulation. 相似文献
44.
In this study, we describe intraspecies variation in the alphaC connector region of the bovine fibrinogen Aalpha gene. Sequencing and genotyping of six bovine breeds revealed 7 to 10 tandem repeats in the alphaC connector region. In addition, we observed length differences between B. indicus and B. taurus, with the B. indicus having longer fibrinogen alphaC connectors (10-repeat alleles) than B. taurus (7- and 9-repeats). The difference in tandem repeats may be related to the function of blood coagulation system. 相似文献
45.
Foxp3 inhibits RORgammat-mediated IL-17A mRNA transcription through direct interaction with RORgammat 总被引:3,自引:0,他引:3
Ichiyama K Yoshida H Wakabayashi Y Chinen T Saeki K Nakaya M Takaesu G Hori S Yoshimura A Kobayashi T 《The Journal of biological chemistry》2008,283(25):17003-17008
The cytokine, transforming growth factor-beta1 (TGF-beta1), converts naive T cells into regulatory T cells that prevent autoimmunity. However, in the presence of interleukin (IL)-6, TGF-beta1 has also been found to promote differentiation into IL-17-producing helper T (Th17) cells that are deeply involved in autoimmunity and inflammation. However, it has not been clarified how TGF-beta1 and IL-6 determine such a distinct fate. Here we found that a master regulator for Th17, retinoic acid-related orphan receptor gammat (RORgammat), was rapidly induced by TGF-beta1 regardless of the presence of IL-6. IL-6 reduced Foxp3 expression, and overexpression of Foxp3 in a T cell line resulted in a strong reduction of IL-17A expression. We have characterized the IL-17A promoter and found that RORgammat binding is sufficient for activation of the minimum promoter in the HEK 293T cells. RORgammat-mediated IL-17A promoter activation was suppressed by forced expression of Foxp3. Foxp3 directly interacted with RORgammat through exon 2 region of Foxp3. The exon 2 region and forkhead (FKH) domain of Foxp3 were necessary for the suppression of RORgammat-mediated IL-17A promoter activation. We propose that induction of Foxp3 is the mechanism for the suppression of Th17 and polarization into inducible Treg. 相似文献
46.
47.
Effects of microsite light availability on the growth and survival of transplantedQuercus serrata Thunb. seedlings in aMiscanthus sinensis Anderss. grass canopy were investigated by a “plant's eye view” approach. Diffuse site factors, i.e., the fractional transmissions
of diffuse photosynthetic photon flux density, were estimated at 15 cm aboveground in 108 microsites where the seedlings grew.
Microsite diffuse site factors were significantly different between surviving and dead seedlings during the experiment period
from April to October (F[1,14]=10.9, P<0.01). Relative growth rate of dry weight for individual seedlings positively depended on the diffuse site factors
(r2=0.482, P<0.001 in May; r2=0.312, P<0.001 in October). Only 16 seedlings produced their second stem flush within the grass canopy. The ratio of height
to dry weight of the second stem flush was significantly higher for the seedlings grew in shady microsites than for those
in less shady microsites (r2=0,471, P<0.01 in May). This study suggests that the microsite heterogeneity of light availability is one of the important
factors affecting the establishment of tree seedlings in patchy grasslands. 相似文献
48.
Hideyuki Yoshida Caleb A. Lareau Ricardo N. Ramirez Samuel A. Rose Barbara Maier Aleksandra Wroblewska Fiona Desland Aleksey Chudnovskiy Arthur Mortha Claudia Dominguez Julie Tellier Edy Kim Dan Dwyer Susan Shinton Tsukasa Nabekura YiLin Qi Bingfei Yu Michelle Robinette Christophe Benoist 《Cell》2019,176(4):897-912.e20
49.
50.
Gene amplification contributes to a variety of biological phenomena, including malignant progression and drug resistance. However, details of the molecular mechanisms remain to be determined. Here, we have developed a gene amplification system in yeast and mammalian cells that is based on double rolling-circle replication (DRCR). Cre-lox system is used to efficiently induce DRCR utilizing a recombinational process coupled with replication. This system shows distinctive features seen in amplification of oncogenes and drug-resistance genes: (i) intra- and extrachromosomal amplification, (ii) intensive chromosome rearrangement and (iii) scattered-type amplification resembling those seen in cancer cells. This system can serve as a model for amplification of oncogenes and drug-resistance genes, and improve amplification systems used for making pharmaceutical proteins in mammalian cells. 相似文献