The impact of soil salinity on the yield, composition and physiology of the bioenergy grass Miscanthus × giganteus

Funded by OPTIMA Biotechnology & Biological Sciences Research Council (BBSRC) Institute Strategic Programme Energy Grasses & Biorefining. Grant Number: BBS/E/W/10963A01 Defra GIANT LINK

Photoperiod- and Triiodothyronine-Dependent Regulation of Reproductive Neuropeptides, Proinflammatory Cytokines, and Peripheral Physiology in Siberian Hamsters (Phodopus sungorus).

Peer reviewed

Diverse roles of the tumor necrosis factor family member TRANCE in skeletal physiology revealed by TRANCE deficiency and partial rescue by a lymphocyte-expressed TRANCE transgene

Tumor necrosis factor-related, activation-induced cytokine (TRANCE), a tumor necrosis factor family member, mediates survival of dendritic cells in the immune system and is required for osteoclast differentiation and activation in the skeleton. We report the skeletal phenotype of TRANCE-deficient mice and its rescue by the TRANCE transgene specifically expressed in lymphocytes. TRANCE-deficient mice showed severe osteopetrosis, with no osteoclasts, marrow spaces, or tooth eruption, and exhibited profound growth retardation at several skeletal sites, including the limbs, skull, and vertebrae. These mice had marked chondrodysplasia, with thick, irregular growth plates and a relative increase in hypertrophic chondrocytes. Transgenic overexpression of TRANCE in lymphocytes of TRANCE-deficient mice rescued osteoclast development in two locations in growing long bones: excavation of marrow cavities permitting hematopoiesis in the marrow spaces, and remodeling of osteopetrotic woven bone in the shafts of long bones into histologically normal lamellar bone. However, osteoclasts in these mice failed to appear at the chondroosseous junction and the metaphyseal periosteum of long bones, nor were they present in tooth eruption pathways. These defects resulted in sclerotic metaphyses with persistence of club-shaped long bones and unerupted teeth, and the growth plate defects were largely unimproved by the TRANCE transgene. Thus, TRANCE-mediated regulation of the skeleton is complex, and impacts chondrocyte differentiation and osteoclast formation in a manner that likely requires local delivery of TRANCE.

A Computer-Assisted Personalized Approach in an Undergraduate Plant Physiology Class1

We used Computer-Assisted Personalized Approach (CAPA), a networked teaching and learning tool that generates computer individualized homework problem sets, in our large-enrollment introductory plant physiology course. We saw significant improvement in student examination performance with regular homework assignments, with CAPA being an effective and efficient substitute for hand-graded homework. Using CAPA, each student received a printed set of similar but individualized problems of a conceptual (qualitative) and/or quantitative nature with quality graphics. Because each set of problems is unique, students were encouraged to work together to clarify concepts but were required to do their own work for credit. Students could enter answers multiple times without penalty, and they were able to obtain immediate feedback and hints until the due date. These features increased student time on task, allowing higher course standards and student achievement in a diverse student population. CAPA handles routine tasks such as grading, recording, summarizing, and posting grades. In anonymous surveys, students indicated an overwhelming preference for homework in CAPA format, citing several features such as immediate feedback, multiple tries, and on-line accessibility as reasons for their preference. We wrote and used more than 170 problems on 17 topics in introductory plant physiology, cataloging them in a computer library for general access. Representative problems are compared and discussed.

Effects of Oxygen on Nodule Physiology and Expression of Nodulins in Alfalfa1

Early nodulin 2 (ENOD2) transcripts and protein are specifically found in the inner cortex of legume nodules, a location that coincides with the site of a barrier to O2 diffusion. The extracellular glycoprotein that binds the monoclonal antibody MAC236 has also been localized to this site. Thus, it has been proposed that these proteins function in the regulation of nodule permeability to O2 diffusion. It would then be expected that the levels of ENOD2 mRNA/protein and MAC236 antigen would differ in nodules with different permeabilities to O2. We examined the expression of ENOD2 and other nodule-expressed genes in Rhizobium meliloti-induced alfalfa nodules grown under 8, 20, or 50% O2. Although there was a change in the amount of MAC236 glycoprotein, the levels of ENOD2 mRNA and protein did not differ significantly among nodules grown at the different [O2], suggesting that neither ENOD2 transcription nor synthesis is involved in the long-term regulation of nodule permeability. Moreover, although nodules from all treatments reduced their permeability to O2 as the partial pressure of O2 (pO2) was increased to 100%, the levels of extractable ENOD2 and MAC236 proteins did not differ from those measured at the growth pO2, further suggesting that if these proteins are involved in a short-term regulation of the diffusion barrier, they must be involved in a way that does not require increased transcription or protein synthesis.