Cognition is a term frequently used in several loosely related ways to refer to a faculty for the human-like processing of information. Signal transduction networks certainly fit that bill, as the mediate adaptive changes in gene expression to specific sensory inputs. Melinda Baker and Jeffry Stock, in the recent issue of Current Biology, elaborate on [...]

Myosin II functions as a molecular motor which facilitates contraction of the actin cytoskeleton during migration, resides outside of protrusions at the front of motile cells, and acts at a distance to impact cell protrusion, signaling, and maturation of nascent adhesions. So clearly myosin II is a protein that is of great importance for understanding [...]

On a couple other blogs, a study published in Science by Joan Steitz1 is being called “One of the biggest findings of the year,” and “If it turns out to be true, this finding just flipped the whole field on its head.” Bitesize Bio would be greatly remiss to not mention to so hot a [...]

There might be more to cell death besides apoptosis and necrosis. In a paper that sounded a bit fishy to me, Michael Overholtzer, Joan Brugge and coworkers1 introduce “Entosis”: A non-apoptotic cell death process, that occurs by cell-in-cell invasion. As Eileen White2 described: Upon examination of mammary epithelial cell lines in suspension, Overholtzer et al. [...]

Looking at the tree of life, descent with modification is an obvious theme, where genes are passed on through ‘vertical’ lines of ancestry. It so happens though that genes can jump from one lineage to another, by a process called ‘horizontal gene transfer’ (HGT). Naked DNA uptake (transformation), viruses (transduction), and plasmids (conjugation) are the [...]

Here’s one of my favorite journal articles from the past year – an elegant study by Natalie Andrew and Robert Insall published in Nature Cell Biology: Chemotaxis in shallow gradients is mediated independently of PtdIns 3-kinase by biased choices between random protrusions. From the introduction: We have made detailed, quantitative observations of Dictyostelium cells chemotaxing [...]

In the budding yeast Saccharomyces cerevisiae, 59 of the 79 cytoplasmic ribosomal proteins are encoded by two genes, stemming from an ancient genome duplication event. Komili et al. (2007) now report that these paralogous genes are not functionally equivalent, suggesting the possible existence of a “ribosome code.”1 Yeast and mammalian genomes are riddled with apparently [...]

Apoptosis, or programmed cell death, is an evolutionarily conserved and neatly orchestrated process important for tissue remodeling and safe elimination of severely damaged cells. Conducted by a caspase-mediated proteolytic cascade, the cell death program results in a series of cellular changes distinct from cellular necrosis. And one of the critical aspects that distinguish apoptosis from [...]

“How many genes are mutated in a human tumor?” That’s the question that a team of researchers at Johns Hopkins posed, and took a comparative genomic approach. By analyzing the sequences of 20,857 transcripts from 18,191 human genes, in 11 breast and 11 colorectal cancers, Wood et al. were able to generate a topographical representation [...]

One of the neat tools in molecular biology is the ability to recombine parts of two proteins to create fusion or chimeras. They’re often extremely useful for simple experiments, some of the time for targeting protein domains to subcellular sites, or to isolate a structural component of a protein. The functional information is often quite [...]