Yeast

About: Yeast is a research topic. Over the lifetime, 31777 publications have been published within this topic receiving 868967 citations. The topic is also known as: yeasts.

Isolation of single-copy human genes from a library of yeast artificial chromosome clones.

Abstract: A recently developed cloning system based on the propagation of large DNA molecules as linear, artificial chromosomes in the yeast Saccharomyces cerevisiae provides a potential method of cloning the entire human genome in segments of several hundred kilobase pairs. Most application of this system will require the ability to recover specific sequences from libraries of yeast artificial chromosome clones and to propagate these sequences in yeast without alterations. Two single-copy genes have now been cloned from a library of yeast artificial chromosome clones that was prepared from total human DNA. Multiple, independent isolates were obtained of the genes encoding factor IX and plasminogen activator inhibitor type 2. The clones, which ranged in size from 60 to 650 kilobases, were stable on prolonged propagation in yeast and appear to contain faithful replicas of human DNA.

Arabidopsis IRT2 gene encodes a root-periphery iron transporter.

Abstract: Iron uptake from the soil is a tightly controlled process in plant roots, involving specialized transporters. One such transporter, IRT1, was identified in Arabidopsis thaliana and shown to function as a broad-range metal ion transporter in yeast. Here we report the cloning and characterization of the IRT2 cDNA, a member of the ZIP family of metal transporters, highly similar to IRT1 at the amino-acid level. IRT2 expression in yeast suppresses the growth defect of iron and zinc transport yeast mutants and enhances iron uptake and accumulation. However, unlike IRT1, IRT2 does not transport manganese or cadmium in yeast. IRT2 expression is detected only in roots of A. thaliana plants, and is upregulated by iron deficiency. By fusing the IRT2 promoter to the uidA reporter gene, we show that the IRT2 promoter is mainly active in the external cell layers of the root subapical zone, and therefore provide the first tissue localization of a plant metal transporter. Altogether, these data support a role for the IRT2 transporter in iron and zinc uptake from the soil in response to iron-limited conditions.

Engineering of protein secretion in yeast: Strategies and impact on protein production

Abstract: Yeasts combine the ease of genetic manipulation and fermentation of a microorganism with the capability to secrete and modify foreign proteins according to a general eukaryotic scheme. Their rapid growth, microbiological safety, and high-density fermentation in simplified medium have a high impact particularly in the large-scale industrial production of foreign proteins, where secretory expression is important for simplifying the downstream protein purification process. However, secretory expression of heterologous proteins in yeast is often subject to several bottlenecks that limit yield. Thus, many studies on yeast secretion systems have focused on the engineering of the fermentation process, vector systems, and host strains. Recently, strain engineering by genetic modification has been the most useful and effective method for overcoming the drawbacks in yeast secretion pathways. Such an approach is now being promoted strongly by current post-genomic technology and system biology tools. However, engineering of the yeast secretion system is complicated by the involvement of many cross-reacting factors. Tight interdependence of each of these factors makes genetic modification difficult. This indicates the necessity of developing a novel systematic modification strategy for genetic engineering of the yeast secretion system. This mini-review focuses on recent strategies and their advantages for systematic engineering of yeast strains for effective protein secretion.

27 – Yeast Promoters and lacZ Fusions Designed to Study Expression of Cloned Genes in Yeast

Abstract: Publisher Summary This chapter describes plasmids and methods for constructing fusions of any cloned gene to lacZ for study in yeast. If the gene to be fused to lacZ contains no appropriate Sau3A sites, alternative strategies to the above must be employed. If the DNA sequence of the gene to be fused to lacZ is known, inframe fusions can be made simply by choosing the appropriate gene fragment. The vector sequences that precede the yeast DNA is a yeast gene–lacZ fusion may affect gene regulation. Plasmids may be used to probe the signals that govern the initiation of transcription and translation in S. cerevisiae. These methods provide powerful tools in the analysis of the expression of yeast genes. Further, the plasmids should facilitate the expression in yeast of any cloned gene to produce the native, unfused product.