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1.
A survey of cultivated heirloom tomato varieties identifies four new mutant alleles at the green-flesh locus 总被引:1,自引:0,他引:1
Cornelius S. Barry Priyanka Pandey 《Molecular breeding : new strategies in plant improvement》2009,24(3):269-276
The process of crop domestication occurs through the selection and subsequent propagation of novel alleles that improve traits
of interest. Cultivated tomato (Solanum lycopersicum), particularly heirloom varieties, exhibit a wide range of variation in fruit size, shape and color. The green-flesh mutant of tomato possesses a stay-green phenotype resulting in fruits that ripen to a red-brown color, due to the retention
of chlorophyll and the simultaneous accumulation of lycopene. The recent identification of the GREEN-FLESH gene provides a molecular tool with which to investigate the origin of a subset of cultivated tomato varieties that resemble
the green-flesh mutant. Sequence analysis of the GF locus from 26 varieties revealed the existence of four previously unidentified null alleles. This study illustrates the potential
of cultivated tomato varieties, including heritage cultivars, heirlooms, and land races, for uncovering new alleles in genes
of interest. 相似文献
2.
Nicolas Delaleu Heike Immervoll Janet Cornelius Roland Jonsson 《Arthritis research & therapy》2008,10(1):R22
Introduction
Sj?gren's syndrome (SS) is a systemic autoimmune disease that mainly targets the exocrine glands. The aim of this study was to investigate the involvement of 87 proteins measured in serum and 75 proteins analyzed in saliva in spontaneous experimental SS. In addition, we intended to compute a model of the immunological situation representing the overt disease stage of SS. 相似文献3.
A new method for the analysis of NMR data in terms of the solution structure of proteins has been developed. The method consists of two steps: first a systematic search of the conformational space to define the region allowed by the initial set of experimental constraints, and second, the narrowing of this region by the introduction of additional constraints and optional refinement procedures. The search of the conformational space is guided by heuristics to make it computationally feasible. The method is therefore called the heuristic refinement method and is coded in an expert system called PROTEAN. The paper describes the validation of the first step of the method using an artificial NMR data set generated from the known crystal structure of sperm whale carbon monoxymyoglobin. It is shown that the initial search procedure yields a low-resolution structure of the myoglobin molecule, accurately reproducing its main topological features, and that the precision of the structure depends on the quality of the initial data set. 相似文献
4.
A variety of plant secondary compounds, several of which are quite widespread in nature were tested for their deterrence to the specialist coleopteran Hypera brunneipennis (Boheman) in short-term behavioral assays. The compounds were nicotine, quinine, sparteine, hordenine, linamarin, amygdalin, sinigrin, morin, juglone, chlorogenic acid, digitonin, mimosine, diosgenin, rutin and ursolic acid. Nine of these were then tested for their post-ingestional effects over one to two weeks of adult life, using fecundity as a measure of the effects. In only one case was there any indication of a detrimental effect or any trend suggesting one. The evolutionary implications of these findings are discussed. 相似文献
5.
6.
Caldesmon inhibits skeletal actomyosin subfragment-1 ATPase activity and the binding of myosin subfragment-1 to actin 总被引:6,自引:0,他引:6
Smooth muscle contraction is controlled in part by the state of phosphorylation of myosin. A recently discovered actin and calmodulin-binding protein, named caldesmon, may also be involved in regulation of smooth muscle contraction. Caldesmon cross-links actin filaments and also inhibits actin-activated ATP hydrolysis by myosin, particularly in the presence of tropomyosin. We have studied the effect of caldesmon on the rate of hydrolysis of ATP by skeletal muscle myosin subfragment-1, a system in which phosphorylation of the myosin is not important in regulation. Caldesmon is a very effective inhibitor of ATP hydrolysis giving up to 95% inhibition. At low ionic strength (approximately 20 mM) this effect does not require smooth muscle tropomyosin, whereas at high ionic strength (approximately 120 mM) tropomyosin enhances the inhibitory activity of caldesmon at low caldesmon concentrations. Cross-linking of actin is not essential for inhibition of ATP hydrolysis to occur since at high ionic strength there is very little cross-linking as determined by a low speed sedimentation assay. Under all conditions examined, the decrease in the rate of ATP hydrolysis is accompanied by a decrease in the binding of myosin subfragment-1 to actin. Furthermore, caldesmon weakens the equilibrium binding of myosin subfragment-1 to actin in the presence of pyrophosphate. We conclude that caldesmon has a general weakening effect on the binding of skeletal muscle myosin subfragment-1 to actin and that this weakening in binding may be responsible for inhibition of ATP hydrolysis. 相似文献
7.
Bolivian squirrel monkeys, unlike those of Brazilian origin, exhibit a marked fasting hyperbilirubinemia (FH) similar to that observed in Gilbert's syndrome in man. Since no delays in the hepatic clearance of sulfobromophthalein or indocyanine green are present, the Bolivian monkey appears to be similar to Gilbert's type I syndrome. FH can be significantly decreased by either phenobarbital or tin-protoporphyrin pretreatment. Nicotinic acid-induced hyperbilirubinemia and delayed tolbutamide clearance were not observed as in the human syndrome. 相似文献
8.
Ferdinand Bohlmann Cornelius Scheidges Laxmi N. Misra Jasmin Jakupovic 《Phytochemistry》1984,23(8):1795-1798
The investigation of three South African Vernonia species afforded minute amounts of five new glaucolides, two monoepoxides and three diepoxides. The structures were elucidated by 1H NMR spectroscopy. The roots of Vernonia sutherlandii contain, in addition to vernonataloide, bergamotene and santalene, minute amounts of the corresponding acetoxy derivatives. 相似文献
9.
Allelopathy as a factor in ecological process 总被引:6,自引:0,他引:6
Cornelius H. Muller 《Plant Ecology》1969,18(1-6):348-357
Zusammenfassung Allelopathie (chemische Hemmung) ist ein Faktor bei ökologischen Prozessen wie Konkurrenz, Dominanz, Sukzession, Produktivität.Es ist zu erwarten daß die von Pflanzen ausgeschiedenen Chemikalien sich in der Umgebung der Pflanze ansammeln, bis sie für andere Pflanzen, oder für ihre eigene Entwicklung, eine hemmende Konzentration erreichen. Auch steht es fest, daß manche Pflanzen sich so gegen Tierfraß schützen.Biochemische Produkte kommen weitgehend in biotischen Wechselwirkungen vor und allelopathische Effekte spielen in fast allen natürlichen oder angepflanzten Pflanzengemeinschaften eine Rolle.
This study has been supported by National Science Foundation, contracts GB-149, GB-4058, and GB-6814, under which this is the tenth publication. 相似文献
This study has been supported by National Science Foundation, contracts GB-149, GB-4058, and GB-6814, under which this is the tenth publication. 相似文献
10.