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991.
Although multiple environmental cues regulate the transition to flowering in Arabidopsis thaliana, previous studies have suggested that wild A. thaliana accessions fall primarily into two classes, distinguished by their requirement for vernalization (extended winter-like temperatures), which enables rapid flowering under long days. Much of the difference in vernalization response is apparently due to variation at two epistatically acting loci, FRI and FLC. We present the response of over 150 wild accessions to three different environmental variables. In long days, FLC is among those genes whose expression is most highly correlated with flowering. In short days, FRI and FLC are less important, although their contribution is still significant. In addition, there is considerable variation not only in vernalization response, but also in the response to differences in day length or ambient growth temperature. The identification of accessions that flower relatively early or late in specific environments suggests that many of the flowering-time pathways identified by mutagenesis, such as those that respond to day length, contribute to flowering-time variation in the wild. In contrast to differences in vernalization requirement, which are mainly mediated by FRI and FLC, it seems that variation in these other pathways is due to allelic effects at several different loci. 相似文献
992.
Ayyadevara S Engle MR Singh SP Dandapat A Lichti CF Benes H Shmookler Reis RJ Liebau E Zimniak P 《Aging cell》2005,4(5):257-271
Caenorhabditis elegans expresses a glutathione transferase (GST) belonging to the Pi class, for which we propose the name CeGSTP2-2. CeGSTP2-2 (the product of the gst-10 gene) has the ability to conjugate the lipid peroxidation product 4-hydroxynonenal (4-HNE). Transgenic C. elegans strains were generated in which the 5'-flanking region and promoter of gst-10 were placed upstream of gst-10 and mGsta4 cDNAs, respectively. mGsta4 encodes the murine mGSTA4-4, an enzyme with particularly high catalytic efficiency for 4-HNE. The localization of both transgenes was similar to that of native CeGSTP2-2. The 4-HNE-conjugating activity in worm lysates increased in the order: control相似文献
993.
Fenneropenaeus indicus could be protected from white spot disease (WSD) caused by white spot syndrome virus (WSSV) using a formalin-inactivated viral preparation (IVP) derived from WSSV-infected shrimp tissue. The lowest test quantity of lyophilized IVP coated onto feed at 0.025 g(-1) (dry weight) and administered at a rate of 0.035 g feed g(-1) body weight d(-1) for 7 consecutive days was sufficient to provide protection from WSD for a short period (10 d after cessation of IVP administration). Shrimp that survived challenges on the 5th and 10th days after cessation of IVP administration survived repeated challenges although they were sometimes positive for the presence of WSSV by a polymerase chain reaction (PCR) assay specific for WSSV. These results suggest that F. indicus can be protected from WSD by simple oral administration of IVP. 相似文献
994.
Rai R Singh AK Singh BD Joshi AK Chand R Srivastava CP 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,123(5):803-813
Pea rust caused by Uromyces fabae (Pers.) de-Bary is a major problem in warm humid regions causing huge economic losses. A mapping population of 136 F6:7 recombinant inbred lines (RILs) derived from the cross between pea genotypes, HUVP 1 (susceptible) and FC 1 (resistant) was
evaluated in polyhouse as well as under field conditions during two consecutive years. Infection frequency (IF) and area under
disease progress curve (AUDPC) were used for evaluation of rust reaction of the RILs. A linkage map was constructed with 57
polymorphic loci selected from 148 simple sequence repeats (SSRs), 3 sequence tagged sites (STS), and 2 random amplified polymorphic
(RAPD) markers covering 634 cM of genetic distance on the seven linkage groups of pea with an average interval length of 11.3 cM.
Composite interval mapping (CIM) revealed one major (Qruf) and one minor (Qruf1) QTL for rust resistance on LGVII. The LOD (5.2–15.8) peak for Qruf was flanked by SSR markers, AA505 and AA446 (10.8 cM), explaining 22.2–42.4% and 23.5–58.8% of the total phenotypic variation
for IF and AUDPC, respectively. The minor QTL was environment-specific, and it was detected only in the polyhouse (LOD values
4.2 and 4.8). It was flanked by SSR markers, AD146 and AA416 (7.3 cM), and explained 11.2–12.4% of the total phenotypic variation.
The major QTL Qruf was consistently identified across all the four environments. Therefore, the SSR markers flanking Qruf would be useful for marker-assisted selection for pea rust (U. fabae) resistance. 相似文献
995.
Cross-linked enzyme aggregates (CLEAs) are prepared by precipitation of an enzyme and then chemical cross-linking the precipitate. Three CLEAs of lipase with glutaraldehyde concentrations of 10 mM (CLEA A), 40 mM (CLEA B) and 60 mM (CLEA C) were prepared. Studies show that there is a trade-off between thermal stability vs transesterification/hydrolysis rate vs enantioselectivity. The initial rates for transesterification of β-citronellol for the uncross-linked enzyme and CLEAs A, B and C were 243, 167, 102 and 40 µmol mg?1 h?1, respectively. Their thermal stabilities in aqueous media, as reflected by their half-life values at 55°C, were 6, 9, 13 and 16 h, respectively. The enantioselectivity, E values (for kinetic resolution of β-citronellol by transesterification) were 19, 74, 11 and 6, respectively. These results show that CLEA C was the most thermostable; the uncross-linked enzyme was best at obtaining the highest transesterification rate; and CLEA A was best suited for the enantioselective synthesis. Scanning electron microscopy (SEM) showed that the morphology of CLEA was dependent upon the extent of cross-linking. 相似文献
996.
Rohini Bhat Anil Kumar Singh Muntazir Mushtaq Romesh Kumar Salgotra Manmohan Sharma Basharat Ahmad Bhat Umer Basu Ibrahim Al-Ashkar Mohammad Anwar Hossain Akihiro Ueda Ayman El Sabagh 《Phyton》2022,91(11):2439-2459
Identification of quantitative trait loci (QTLs) controlling yield and yield-related traits in rice was performed in
the F2 mapping population derived from parental rice genotypes DHMAS and K343. A total of 30 QTLs governing nine different traits were identified using the composite interval mapping (CIM) method. Four QTLs were
mapped for number of tillers per plant on chromosomes 1 (2 QTLs), 2 and 3; three QTLs for panicle number
per plant on chromosomes 1 (2 QTLs) and 3; four QTLs for plant height on chromosomes 2, 4, 5 and 6; one
QTL for spikelet density on chromosome 5; four QTLs for spikelet fertility percentage (SFP) on chromosomes
2, 3 and 5 (2 QTLs); two QTLs for grain length on chromosomes 1 and 8; three QTLs for grain width on chromosomes1, 3 and 8; three QTLs for 1000-grain weight (TGW) on chromosomes 1, 4 and 8 and six QTLs for yield
per plant (YPP) on chromosomes 2 (3 QTLs), 4, 6 and 8. Most of the QTLs were detected on chromosome 2, so
further studies on chromosome 2 could help unlock some new chapters of QTL for this cross of rice variety. Identified QTLs elucidating high phenotypic variance can be used for marker-assisted selection (MAS) breeding.
Further, the exploitation of information regarding molecular markers tightly linked to QTLs governing these traits
will facilitate future crop improvement strategies in rice. 相似文献
997.
998.
999.
Yogesh B. Wagh Kundan C. Tayade Anil Kuwar Suban K. Sahoo Mayank Narinder Singh Dipak S. Dalal 《Luminescence》2020,35(3):379-384
Abstract In this study, the recognition contour of Chemosensor 1 was investigated using semiaqueous methanol (XH, mole fraction = 0.31) for a range of anions and bioactive species. Host–receptor signalling based on the internal charge transfer mechanism for Chemosensor 1 was explored and reported. Structure of Chemosensor 1 and its plausible anion coordination based on hydrogen bonding is complemented with density functional theory. Consequently, we investigated the applicability of the synthesized probe in blood plasma, urine, tap water samples, and for monitoring of ATP in lysosomes by apyrase enzyme. 相似文献
1000.