Highlights from the August 2010 Issue of DNA and Cell Biology

T his month's issue features two especially interesting papers, one on bacterial biofilms and the other exploring the role of host genetic background in mouse knockout phenotypes. Tetz and Tetz report on the role of extracellular DNA in bacterial biofilm formation in their article, “Effect of Extracellular DNA Destruction by DNase I on Characteristics of Forming Biofilms.” Biofilm formation is important in many disease processes and as well as in microbial community development. Biofilm architecture changes with DNase I application. Tetz and Tetz report that biofilms formed in the presence of DNase I displayed reduced biofilm biomass, reduced total bacterial biomass, decreased bacterial viability, and decreased tolerance to antibiotics.

Fibroblast growth factor-16 (FGF-16) is important for the growth and development of the embryonic myocardium in mice. Disruption of Fgf-16 effects cardiac development; however, the severity of the defects varies in different strains of mice. Lu et al. investigate the role of host genetics in the phenotypes of Fgf-16 knockout mice in their article, “Embryonic Survival and Severity of Cardiac and Craniofacial Defects Are Affected by Genetic Background in Fibroblast Growth Factor-16 Null Mice.” They found that after three generations, back-crossing a Fgf-16 mutation into C57BL/6 mice led to survival of about 25% of potential Fgf-16 null mice while no Fgf-16 Black Swiss null mice survived. Lu and colleagues also found that FGF-8 RNA levels were reduced in Black Swiss, but not C57BL/6 mice. Basal expression levels of related genes also varied between mouse strains. Host modulation of gene expression may partially explain the differences in phenotypes seen in various lines of Fgf-16 knockout mice.