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排序方式: 共有373条查询结果,搜索用时 15 毫秒
1.
有研究表明,干旱、低温和盐等环境胁迫能够诱导LEA基因的表达。为了探索LEA基因家族在高粱响应外界刺激过程中起到的作用,本研究通过生物信息学的方法对LEA基因家族在高粱全基因组水平进行鉴定和分析,于高粱全基因组中共鉴定出35个基因家族成员,不均匀地分布于高粱8条染色体上,结合系统进化树和保守结构域分析结果,将高粱LEA基因家族成员分为7组。亲水性分析和结构无序性预测表明高粱LEA蛋白绝大多数为亲水性且结构无序。基因结构分析显示了各分组基因结构上的保守性。高粱LEA基因的启动子分析发现了一些与激素和非生物胁迫响应相关的顺式作用元件。对激素和干旱胁迫下高粱LEA基因的表达分析发现外界胁迫能够诱导部分高粱LEA基因的表达。 相似文献
2.
Spatial distribution of root activity and nitrogen fixation in sorghum/pigeonpea intercropping on an Indian Alfisol 总被引:2,自引:0,他引:2
Ito Osamu Matsunaga Ryoichi Tobita Satoshi Rao Theertham P. Devi Y. Gayatri 《Plant and Soil》1993,155(1):341-344
A medium-duration pigeonpea cultivar (ICP 1–6) and a hybrid sorghum (CSH 5) were grown on a shallow Alfisol in monocropping and intercropping systems. Using a monolith method, spatial distribution of nodulation, acetylene reduction activity (ARA) and root respiration were measured.The number, mass and ARA of nodules decreased exponentially with distance from the plant base except at the late reproductive stage. Nodulation and ARA tended to be higher in the intercrop than in the monocrop.Respiration rate of roots increased with distance from the plant base and reached a maximum value at about 20–30 cm. The rate was higher in pigeonpea than in sorghum and also higher in intercrop than in monocrop.This study suggests that pigeonpea roots are physiologically more active than sorghum roots, implying that pigeonpea may become a strong competitor for nutrients in the soil when intercropped. The nitrogen-fixing ability of pigeonpea may be enhanced by intercropping because the sorghum rapidly absorbed inorganic N which would otherwise inhibit N2 fixation. 相似文献
3.
微生物中控制脯氨酸合成的渗透调节基因(osm基因)的转移成功及其抗渗透胁迫能力的提高(Csonka 1980,1981,Le Rudulier和Valentine 1981),启发科学家们把注意力投向高等植物,特别是有经济价值的作物(Bodnar等1989,Nelson等1988,1989,Sanada等1989,Higgins等1987)。采用蛋白质合成抑制剂亚胺环 相似文献
4.
Saballos A Sattler SE Sanchez E Foster TP Xin Z Kang C Pedersen JF Vermerris W 《The Plant journal : for cell and molecular biology》2012,70(5):818-830
Successful modification of plant cell-wall composition without compromising plant integrity is dependent on being able to modify the expression of specific genes, but this can be very challenging when the target genes are members of multigene families. 4-coumarate:CoA ligase (4CL) catalyzes the formation of 4-coumaroyl CoA, a precursor of both flavonoids and monolignols, and is an attractive target for transgenic down-regulation aimed at improving agro-industrial properties. Inconsistent phenotypes of transgenic plants have been attributed to variable levels of down-regulation of multiple 4CL genes. Phylogenetic analysis of the sorghum genome revealed 24 4CL(-like) proteins, five of which cluster with bona fide 4CLs from other species. Using a map-based cloning approach and analysis of two independent mutant alleles, the sorghum brown midrib2 (bmr2) locus was shown to encode 4CL. In vitro enzyme assays indicated that its preferred substrate is 4-coumarate. Missense mutations in the two bmr2 alleles result in loss of 4CL activity, probably as a result of improper folding as indicated by molecular modeling. Bmr2 is the most highly expressed 4CL in sorghum stems, leaves and roots, both at the seedling stage and in pre-flowering plants, but the products of several paralogs also display 4CL activity and compensate for some of the lost activity. The contribution of the paralogs varies between developmental stages and tissues. Gene expression assays indicated that Bmr2 is under auto-regulatory control, as reduced 4CL activity results in over-expression of the defective gene. Several 4CL paralogs are also up-regulated in response to the mutation. 相似文献
5.
Jae-Myun Ryu Gwi Yeong Jang Dongsun Park Koan Sik Woo Tae Myoung Kim Heon Sang Jeong 《Bioscience, biotechnology, and biochemistry》2013,77(12):2101-2108
ABSTRACTBenign prostatic hyperplasia (BPH) is commonly observed in men > 50 years worldwide. Phytotherapy is one of the many treatment options. Sorghum (Sorghum bicolor L.) contains various health-improving phytochemicals with antioxidant and inhibitory activities on cell proliferation, both in vitro and in vivo. To confirm the effects of Donganme sorghum ethyl-acetate extract (DSEE) on BPH, we induced BPH in Spragye–Dawley rats using exogenous testosterone. We measured prostate weight, examined prostrates histopathologically, and analyzed mRNAs associated with male hormones and proteins associated with cell proliferation in the prostate. DSEE inhibited weight gain of the prostate; decreased mRNA expressions of androgen receptor and 5α-reductase II; and improved histopathological symptoms, the protein-expressed ratio of Bax/Bcl-2, and the oxidative status of BPH induced by testosterone in SD rats. Therefore, DSEE may have potential as a preventive or therapeutic agent against BPH. 相似文献
6.
Developmental changes and effects of various abiotic stresses on peptidyl prolyl cis-trans isomerase (PPIase) activity were studied in the seedlings of sorghum [Sorghum bicolor (L.) Moench cv. CSH-6]. The PPIase activity of sorghum seedlings markedly decreased after two days of germination. Up to
90 % of the PPIase activity was inhibited by cyclosporin-A. Maximal increase in specific PPIase activity in the 3-d-old seedlings
was observed in response to osmotic stress and it was transient in nature. The stress-induced enhancement in PPIase activity,
depending upon tissue and stress treatment, was due to induction of cyclophilins as well as other PPIases. Osmotic stress-induced
enhancement in PPIase activity in the drought susceptible cv. SPRU-94008B was maximal in roots, as compared to shoots in the
drought tolerant cv. ICSV-272.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
Kimberley B. Ritter David R. Jordan Scott C. Chapman Ian D. Godwin Emma S. Mace C. Lynne McIntyre 《Molecular breeding : new strategies in plant improvement》2008,22(3):367-384
QTL for stem sugar-related and other agronomic traits were identified in a converted sweet (R9188) × grain (R9403463-2-1)
sorghum population. QTL analyses were conducted using phenotypic data for 11 traits measured in two field experiments and
a genetic map comprising 228 SSR and AFLP markers grouped into 16 linkage groups, of which 11 could be assigned to the 10
sorghum chromosomes (SBI-01 to SBI-10). QTL were identified for all traits and were generally co-located to five locations
(SBI-01, SBI-03, SBI-05, SBI-06 and SBI-10). QTL alleles from R9188 were detected for increased sucrose content and sugar
content on SBI-01, SBI-05 and SBI-06. R9188 also contributed QTL alleles for increased Brix on SBI-05 and SBI-06, and increased
sugar content on SBI-03. QTL alleles from R9403463-2-1 were found for increased sucrose content and sucrose yield on SBI-10,
and increased glucose content on SBI-07. QTL alleles for increased height, later flowering and greater total dry matter yield
were located on SBI-01 of R9403463-2-1, and SBI-06 of R9188. QTL alleles for increased grain yield from both R9403463-2-1
and R9188 were found on SBI-03. As an increase in stem sugars is an important objective in sweet sorghum breeding, the QTL
identified in this study could be further investigated for use in marker-assisted selection of sweet sorghum. 相似文献
8.
Assessment of genetic diversity and relationship among a collection of US sweet sorghum germplasm by SSR markers 总被引:1,自引:0,他引:1
M. L. Ali J. F. Rajewski P. S. Baenziger K. S. Gill K. M. Eskridge I. Dweikat 《Molecular breeding : new strategies in plant improvement》2008,21(4):497-509
Sweet sorghum (Sorghum bicolor L.) is a type of cultivated sorghums and has been recognized widely as potential alternative source of bio-fuel because of
its high fermentable sugar content in the stalk. A substantial variation of sugar content and related traits is known to exist
in US sweet sorghum. The objectives of the study were to assess the genetic diversity and relationship among the US sweet
sorghum cultivars and lines using SSR markers and to examine the genetic variability within sweet sorghum accessions for sugar
content. Sixty-eight sweet sorghum and four grain sorghum cultivars and lines were genotyped with 41 SSR markers that generated
132 alleles with an average of 3.22 alleles per locus. Polymorphism information content (PIC) value, a measure of gene diversity,
was 0.40 with a range of 0.03–0.87. The genetic similarity co-efficient was estimated based on the segregation of the 132
SSR alleles. Clustering analysis based on the genetic similarity (GS) grouped the 72 sorghum accessions into 10 distinct clusters.
Grouping based on clustering analysis was in good agreement with available pedigree and genetic background information. The
study has revealed the genetic relationship of cultivars with unknown parentage to those with known parentage. A number of
diverse pairs of sweet sorghum accessions were identified which were polymorphic at many SSR loci and significantly different
for sugar content as well. Information generated from this study can be used to select parents for hybrid development to maximize
the sugar content and total biomass, and development of segregating populations to map genes controlling sugar content in
sweet sorghum. 相似文献
9.
The mechanism of calcium uptake, translocation and accumulation in Poaceae has not yet been fully understood. To address this issue, we conducted genome-wide comparative in silico analysis of the calcium (Ca2+) transporter gene family of two crop species, rice and sorghum. Gene annotation, identification of upstream cis-acting ele- ments, phylogenetic tree construction and syntenic mapping of the gene family were performed using several bio- informatics tools. A total of 31 Ca2+ transporters, distributed on 9 out of 12 chromosomes, were predicted from rice genome, while 28 Ca2+ transporters predicted from sorghum are distributed on all the chromosomes except chromosome 10 (Chr 10). Interestingly, most of the genes on Chr 1 and Chr 3 show an inverse syntenic relation- ship between rice and sorghum. Multiple sequence alignment and motif analysis of these transporter proteins re- vealed high conservation between the two species. Phylogenetic tree could very well identify the subclasses of channels, ATPases and exchangers among the gene family. The in silico cis-regulatory element analysis suggested diverse functions associated with light, stress and hormone responsiveness as well as endosperm- and meris- tem-specific gene expression. Further experiments are warranted to validate the in silico analysis of the predicted transporter gene family and elucidate the functions of Ca2+ transporters in various biological processes. 相似文献
10.
《Animal : an international journal of animal bioscience》2015,9(7):1120-1130
A meta-analysis was conducted (i) to evaluate broiler response to partial or total substitution of corn by sorghum and millet and (ii) to determine the effect of soybean meal replacement by cottonseed meal in broiler diet. The database included 190 treatments from 29 experiments published from 1990 to 2013. Bird responses to an experimental diet were calculated relative to the control (Experimental−Control), and were submitted to mixed-effect models. Results showed that diets containing millet led to similar performance as the corn-based ones for all parameters, whereas sorghum-based diets decreased growth performance. No major effect of the level of substitution was observed with millet or cottonseed meal. No effect of the level of substitution of sorghum on feed intake was found; however, growth performance decreased when the level of substitution of corn by sorghum increased. Cottonseed meal was substituted to soybean meal up to 40% and found to increase feed intake while reducing growth performance. Young birds were not more sensitive to these ingredients than older birds since there was no negative effect of these ingredients on performance in the starter phase. Results obtained for sorghum pointed out the necessity to find technological improvements that will increase the utilization of these feedstuffs in broiler diet. An additional work is scheduled to validate these statistical results in vivo and to evaluate the interactions induced with the simultaneous inclusions of sorghum, millet and cottonseed meal in broiler feeding. 相似文献