The Spheres of Influence, “Assessing Assays” (Schmidt 2002), in the May 2002 issue of EHP criticizes the National Toxicology Program rodent bioassay (NTPRB) without discussing its importance in regulation and public health. The Spheres article (Schmidt 2002) does not express concern for the validity of alternative transgenic methods proposed to replace the NTPRB for detecting carcinogens. By fo...

Ploidy level affects cell size in many organisms, and ploidy-dependent cell enlargement has been used to breed many useful organisms. However, how polyploidy affects cell size remains unknown. Previous studies have explored changes in transcriptome data caused by polyploidy, but have not been successful. The most naïve theory explaining ploidy-dependent cell enlargement is that increases in gen...

Molecular genetics approaches in zebrafish research are hampered by the lack of a ubiquitous transgene driver element that is active at all developmental stages. Here, we report the isolation and characterization of the zebrafish ubiquitin (ubi) promoter, which drives constitutive transgene expression during all developmental stages and analyzed adult organs. Notably, ubi expresses in all blood...

The Nile tilapia (Oreochromis niloticus) is an important species in aquaculture and an excellent model system for laboratory studies. Functional genetic analysis using this species has been difficult because existing methods for producing transgenics are inefficient. Here we show that the Tol2 transposon system can be used to create transgenic tilapia with high efficiency. We constructed a line...

Shoot phenology interacts with crown morphology to determine leaf production and duration over the growing season and throughout a tree’s life span; and thus, this interaction has a major role in determining whole-tree photosynthesis and biomass yield. For several years, the pattern of shoot meristem activity determines Populus crown architecture, but after the first onset of flowering the spec...

BACKGROUND Sugarcane, a tropical C4 perennial crop, is capable of producing 30-100 tons or more of biomass per hectare annually. The lignocellulosic residue remaining after sugar extraction is currently underutilized and can provide a significant source of biomass for the production of second-generation bioethanol. RESULTS MYB31 and MYB42 were cloned from maize and expressed in sugarcane with...