To understand the role of free histidine (His) in Ni hyperaccumulation in Thlaspi goesingense, we investigated the regulation of His biosynthesis at both the molecular and biochemical levels. Three T. goesingense cDNAs encoding the following His biosynthetic enzymes, ATP phosphoribosyltransferase (THG1, GenBank accession no. AF003347), imidazoleglycerol phosphate dehydratase (THB1, GenBank acce...

* The extreme phenotype of zinc (Zn) hyperaccumulation, which is found in several Brassicaceae species, is determined by mechanisms that promote elevated Zn tolerance and high Zn accumulation in shoots. * We used reciprocal grafting between a Zn hyperaccumulator, Thlaspi caerulescens, and a Zn nonaccumulator, Thlaspi perfoliatum, to determine the relative importance of roots and shoots in Zn hy...

Field pennycress (Thlaspi arvense L.) is a winter annual weed with a cold requirement for reproductive development. Previous work in this laboratory has demonstrated that the bolting aspect (rapid stem growth) of reproductive development is mediated by gibberellins (GA). The present paper describes the selection and characterization of a mutant lacking the capacity for thermoinduced stem growth...

Title of Document: ECOLOGICAL INTERACTIONS OF THE CADMIUMAND ZINCHYPERACCUMULATING PLANT, THLASPI CAERULESCENS, AND THEIR IMPLICATIONS FOR PHYTOREMEDIATION Judy P. Che-Castaldo Doctor of Philosophy, 2011 Directed By: Dr. David W. Inouye Department of Biology The success of invasive species can be attributed to a combination of abiotic factors, such as abundant resources and favorable climate, a...

A Cd2+-selective vibrating microelectrode was constructed using a neutral carrier-based Cd ionophore to investigate ion-transport processes along the roots of wheat (Triticum aestivum L.) and two species of Thlaspi, one a Zn/Cd hyperaccumulator and the other a related nonaccumulator. In simple Cd(NO3)2 solutions, the electrode exhibited a Nernstian response in solutions with Cd2+ activities as ...

Title of dissertation: EFFICIENCY AND ECOLOGICAL RISKS OF REDUCING SOIL PH DURING THLASPI CAERULESCENS PHYTOEXTRACTION OF CADMIUM AND ZINC Shengchun Wang, Doctor of Philosophy, 2004 Dissertation directed by: Professor Jay Scott Angle Department of Natural Resource Sciences and Landscape Architecture The major aims of this research were to determine whether reducing soil pH can enhance phytoextr...