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101.
SuiKang Wang YouHuang Bai ChenJia Shen YunRong Wu SaiNa Zhang DeAn Jiang Tom J. Guilfoyle Ming Chen YanHua Qi 《Functional & integrative genomics》2010,10(4):533-546
Sorghum, a C4 model plant, has been studied to develop an understanding of the molecular mechanism of resistance to stress.
The auxin-response genes, auxin/indole-3-acetic acid (Aux/IAA), auxin-response factor (ARF), Gretchen Hagen3 (GH3), small
auxin-up RNAs, and lateral organ boundaries (LBD), are involved in growth/development and stress/defense responses in Arabidopsis and rice, but they have not been studied in sorghum. In the present paper, the chromosome distribution, gene duplication,
promoters, intron/exon, and phylogenic relationships of Aux/IAA, ARF, GH3, and LBD genes in sorghum are presented. Furthermore,
real-time PCR analysis demonstrated these genes are differently expressed in leaf/root of sorghum and indicated the expression
profile of these gene families under IAA, brassinosteroid (BR), salt, and drought treatments. The SbGH3 and SbLBD genes, expressed
in low level under natural condition, were highly induced by salt and drought stress consistent with their products being
involved in both abiotic stresses. Three genes, SbIAA1, SbGH3-13, and SbLBD32, were highly induced under all the four treatments,
IAA, BR, salt, and drought. The analysis provided new evidence for role of auxin in stress response, implied there are cross
talk between auxin, BR and abiotic stress signaling pathways. 相似文献
102.
Andrew Ferguson Thomas E. Reed Tom F. Cross Philip McGinnity Paulo A. Prodöhl 《Journal of fish biology》2019,95(3):692-718
Brown trout Salmo trutta is endemic to Europe, western Asia and north-western Africa; it is a prominent member of freshwater and coastal marine fish faunas. The species shows two resident (river-resident, lake-resident) and three main facultative migratory life histories (downstream–upstream within a river system, fluvial–adfluvial potamodromous; to and from a lake, lacustrine–adfluvial (inlet) or allacustrine (outlet) potamodromous; to and from the sea, anadromous). River-residency v. migration is a balance between enhanced feeding and thus growth advantages of migration to a particular habitat v. the costs of potentially greater mortality and energy expenditure. Fluvial–adfluvial migration usually has less feeding improvement, but less mortality risk, than lacustrine–adfluvial or allacustrine and anadromous, but the latter vary among catchments as to which is favoured. Indirect evidence suggests that around 50% of the variability in S. trutta migration v. residency, among individuals within a population, is due to genetic variance. This dichotomous decision can best be explained by the threshold-trait model of quantitative genetics. Thus, an individual's physiological condition (e.g., energy status) as regulated by environmental factors, genes and non-genetic parental effects, acts as the cue. The magnitude of this cue relative to a genetically predetermined individual threshold, governs whether it will migrate or sexually mature as a river-resident. This decision threshold occurs early in life and, if the choice is to migrate, a second threshold probably follows determining the age and timing of migration. Migration destination (mainstem river, lake, or sea) also appears to be genetically programmed. Decisions to migrate and ultimate destination result in a number of subsequent consequential changes such as parr–smolt transformation, sexual maturity and return migration. Strong associations with one or a few genes have been found for most aspects of the migratory syndrome and indirect evidence supports genetic involvement in all parts. Thus, migratory and resident life histories potentially evolve as a result of natural and anthropogenic environmental changes, which alter relative survival and reproduction. Knowledge of genetic determinants of the various components of migration in S. trutta lags substantially behind that of Oncorhynchus mykiss and other salmonines. Identification of genetic markers linked to migration components and especially to the migration–residency decision, is a prerequisite for facilitating detailed empirical studies. In order to predict effectively, through modelling, the effects of environmental changes, quantification of the relative fitness of different migratory traits and of their heritabilities, across a range of environmental conditions, is also urgently required in the face of the increasing pace of such changes. 相似文献
103.
104.
Kretová M Szemes T Laco J Gronesová P Grones J 《Biochemical and biophysical research communications》2005,328(1):27-31
The DNA sequence of small cryptic plasmid pAG20 in Acetobacter aceti was determined at 3064 bp with 51.6% GC pairs. The plasmid encoded a 186 amino acid protein which is important for plasmid replication in Gram-negative bacteria except Escherichia coli. Two 21 bp large direct repeat sequence 1 and two 13 bp direct repeat sequence 2 were determined in the regulation region upstream from gene encoded Rep protein. Vector pAG24 with kanamycin gene and two deletion derivatives pAG25 and pAG26 without rep gene from plasmid pAG20 were constructed. Plasmid pAG24 was replicated in a broad host range like E. coli, Acetobacter pasteurianus, A. aceti, Comanomonas spp., Serratia marcescens, and Shigella spp. 相似文献
105.
106.
Deposits of amyloid β-peptide (Aβ) in senile plaques and cerebral blood vessels is the prominent feature of Alzheimer's disease (AD), regardless of genetic predisposition. The cellular origin of cerebral deposits of Aβ or its precise role in the neurodegenerative process has not been established. Recently we demonstrated a novel action of β-amyloid on blood vessels—vasoactivity and endothelial damage through superoxide radicals. Since endothelial dysfunction is associated with vascular degenerative diseases, we examined the direct action of Aβ on endothelial cells in culture. Cells treated with Aβ displayed characteristics of necrotic cell death which was prevented by the free radical scavenging enzyme superoxide dismutase. Stimulation of endothelial nitric oxide (NO) production by the calcium ionophore, A23187, or bradykinin was inhibited by β-amyloid. We conclude that an imbalance of NO and oxygen radicals may mediate the Aβ-induced endothelial damage on endothelial cells in culture and may also contribute to a variety of pathophysiological conditions associated with aging: hypertension, cerebral ischemia, vasospasm, or stroke. 相似文献
107.
108.
W.Dennis Clark Lowell E. Urbatsch Ronald L. Hartman Richard A. Mayes Tom J. Mabry 《Biochemical Systematics and Ecology》1980,8(3):257-259
Complex flavonoid patterns are correlated with primitive woody taxa and high base chromosome numbers among Haplopappus segregates. Variability among flavonoid complements supports the polyphyletic interpretation of the genus. 相似文献
109.
110.