Cells by Design: A Mini-Review of Targeting Cell Engineering Using DNA Microarrays

Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA.
Molecular Biotechnology (Impact Factor: 1.88). 07/2008; 39(2):105-11. DOI: 10.1007/s12033-008-9048-5
Source: PubMed


Recent studies have demonstrated the utility of DNA microarray technology in engineering cellular properties. For instance, cellular adhesion, the necessity of cells to attach to a surface in order to to proliferate, was examined by comparing two distinct HeLa cell lines. Two genes, one encoding a type II membrane glycosylating sialyltransferase (siat7e) and the other encoding a secreted glycoprotein (lama4), were found to influence adhesion. The expression of siat7e correlated with reduced adhesion, whereas expression of lama4 correlated with increased adhesion, as shown by various assays. In a separate example, a gene encoding a mitochondrial assembly protein (cox15) and a gene encoding a kinase (cdkl3), were found to influence cellular growth. Enhanced expression of either gene resulted in slightly higher specific growth rates and higher maximum cell densities for HeLa, HEK-293, and CHO cell lines. Another investigated property was the adaptation of HEK-293 cells to serum-free media. The genes egr1 and gas6, both with anti-apoptotic properties, were identified as potentially improving adaptability by impacting viability at low serum levels. In trying to control apoptosis, researchers found that by altering the expression levels of four genes faim, fadd, alg-2, and requiem, apoptotic response could be altered. In the present work, these and related studies in microorganisms (prokaryote and eukaryote) are examined in greater detail focusing on the approach of using DNA microarrays to direct cellular behavior by targeting select genes.

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    • "Over the past decade, new tools and strategies for engineering microorganisms have appeared including loss-of-function gene mutations (i.e., gene knock-outs) (Bailey, 1991; Lee et al., 2007; Lee et al., 2005a; Park et al., 2007; Trinh et al., 2006; Trinh et al., 2008), overexpression of gene products (Altaras and Cameron, 1999; Bailey, 1991; Park et al., 2007; Zhang et al., 2007), and introduction of homologous DNA for new or improved functionalities of cells. Today, an increasing amount of success has been achieved by rationally designing strains using these readily available methods (Jaluria et al., 2008; Santos and Stephanopoulos, 2008; Tyo et al., 2007). However, it is difficult to identify an optimal strain by rational design alone, as several parameters that should be considered simultaneously in designs are difficult to predict without a computational approach. "
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