Abstract: The promoter regions associated with the Yarrowia lipolytica glyceraldehyde-3-phosphate dehydrogenase (gpd) and phosphoglycerate mutase (gpm) genes have been found to be particularly effective for the expression of heterologous genes in oleaginous yeast. The promoter regions of the invention have been shown to drive high-level expression of genes involved in the production of ?-3 and ?-6 fatty acids.

Abstract: Micro-scale methods are applied in producing, maintaining, replicating, screening, manipulating and sub-cloning cell libraries. By means of the micro-scale methods of the invention, micro-libraries of single-cells or micro-colonies arranged in a definite two-dimensional pattern are produced, propagated, replicated, screened, examined and manipulated. It is feasible to sub-clone cells and micro-colonies from the micro-libraries, particularly those identified by screening and examining the micro-libraries, for the purposes of purification and large-scale cultivation. Automated and scaleable methods can be applied to screen practically any collection of cells attached to a surface. These methodologies are useful for making and screening on a micro-scale genomic libraries, cDNA libraries, and libraries of hybridoma cells, inter alia. Similar approaches employ such methods and micro-libraries for toxicological, pharmaceutical, mutagenetic and carcinogenic screening.