Programming cell growth into different cluster shapes using diffusible signals.

Advances in genetic engineering technologies have allowed the construction of artificial genetic circuits, which have been used to generate spatial patterns of differential gene expression. However, the question of how cells can be programmed, and how complex the rules need to be, to achieve a desired tissue morphology has received less attention. Here, we address these questions by developing a mathematical model to study how cells can collectively grow into clusters with different structural morphologies by secreting diffusible signals that can influence cellular growth rates. We formulate how growth regulators can be used to control the formation of cellular protrusions and how the range of achievable structures scales with the number of distinct signals. We show that a single growth inhibitor is insufficient for the formation of multiple protrusions but may be achieved with multiple growth inhibitors, and that other types of signals can regulate the shape of protrusion tips. These examples illustrate how our approach could potentially be used to guide the design of regulatory circuits for achieving a desired target structure.

Generation of transgenic goats by pronuclear microinjection: a retrospective analysis of a commercial operation (1995-2012).

Production of transgenic founder goats involves introducing and stably integrating an engineered piece of DNA into the genome of the animal. At LFB USA, the ultimate use of these transgenic goats is for the production of recombinant human protein therapeutics in the milk of these dairy animals. The transgene or construct typically links a milk protein specific promoter sequence, the coding sequence for the gene of interest, and the necessary downstream regulatory sequences thereby directing expression of the recombinant protein in the milk during the lactation period. Over the time period indicated (1995-2012), pronuclear microinjection was used in a number of programs to insert transgenes into 18,120, 1- or 2- cell stage fertilized embryos. These embryos were transferred into 4180 synchronized recipient females with 1934 (47%) recipients becoming pregnant, 2594 offspring generated, and a 109 (4.2%) of those offspring determined to be transgenic. Even with new and improving genome editing tools now available, pronuclear microinjection is still the predominant and proven technology used in this commercial setting supporting regulatory filings and market authorizations when producing founder transgenic animals with large transgenes (> 10 kb) such as those necessary for directing monoclonal antibody production in milk.

A Shift Towards Biotechnology: Social Opinion in the EU.

Consumers' attitude to genetic engineering provides information to stakeholders who are interested in its adoption, which is essential considering the emerging growth of new breeding techniques. This short article analyses, compares, and describes the knowledge, doubts, and concerns of Europeans about biotechnology and genetic engineering over the past 20 years.

DNA patenting: the end of an era?

Debates on patenting DNA must evolve to reflect the global decline in filings and regional disparities in patenting activity.

Engineering microbial consortia: a new frontier in synthetic biology.

Microbial consortia are ubiquitous in nature and are implicated in processes of great importance to humans, from environmental remediation and wastewater treatment to assistance in food digestion. Synthetic biologists are honing their ability to program the behavior of individual microbial populations, forcing the microbes to focus on specific applications, such as the production of drugs and fuels. Given that microbial consortia can perform even more complicated tasks and endure more changeable environments than monocultures can, they represent an important new frontier for synthetic biology. Here, we review recent efforts to engineer synthetic microbial consortia, and we suggest future applications.

Global trends in plant transgenic science and technology (1973-2003).

Transgenic science and technology are fundamental to state-of-the-art plant molecular genetics and GM crop improvement. Monitoring the scale and growth of this area of science is important to scientists, national and international research organizations, funding bodies, policy makers and, because of the GM debate, to society as a whole. Literature statistics covering the past 30 years reveal a dramatic increase in plant transgenic science in Asia during the past decade, a sustained expansion in North America and, recently, a slow down in the rest of the world. With the exception of the output of China and India, publications focusing on the development of transgenic technology have been slowing down, worldwide, since the early mid-1990s, a trend that contrasts with the increase in GM crop-related studies.

Genome Editing and Its Applications in Model Organisms.

Technological advances are important for innovative biological research. Development of molecular tools for DNA manipulation, such as zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and the clustered regularly-interspaced short palindromic repeat (CRISPR)/CRISPR-associated (Cas), has revolutionized genome editing. These approaches can be used to develop potential therapeutic strategies to effectively treat heritable diseases. In the last few years, substantial progress has been made in CRISPR/Cas technology, including technical improvements and wide application in many model systems. This review describes recent advancements in genome editing with a particular focus on CRISPR/Cas, covering the underlying principles, technological optimization, and its application in zebrafish and other model organisms, disease modeling, and gene therapy used for personalized medicine.