Monday, July 9, 2012

Washington Post Cover story on the job prospects of early career PhD Scientists

A few good nuggets:
"The lack of permanent jobs leaves many PhD scientists doing routine laboratory work in low-wage positions known as “post-docs,” or postdoctoral fellowships. Post-docs used to last a year or two, but now it’s not unusual to find scientists toiling away for six, seven, even 10 years. The post-doc system is “dysfunctional and not sustainable in the long term,” Princeton University President Shirley Tilghman told top brass at NIH in June."
“They’ll be employed in something,” said Michael S. Teitelbaum, a senior adviser to the Alfred P. Sloan Foundation who studies the scientific workforce. “But they go and do other things because they can’t find the position they spent their 20s preparing for.

Monday, June 25, 2012

Friday, June 22, 2012

Have you ever thought about how TF find their binding sites?

Transcription factors (TFs) are proteins that regulate the expression of genes by binding sequence-specific sites on the chromosome. It has been proposed that to find these sites fast and accurately, TFs combine one-dimensional (1D) sliding on DNA with 3D diffusion in the cytoplasm. This facilitated diffusion mechanism has been demonstrated in vitro, but it has not been shown experimentally to be exploited in living cells. We have developed a single-molecule assay that allows us to investigate the sliding process in living bacteria. Here we show that the lac repressor slides 45 ± 10 base pairs on chromosomal DNA and that sliding can be obstructed by other DNA-bound proteins near the operator. Furthermore, the repressor frequently (>90%) slides over its natural lacO1 operator several times before binding. This suggests a trade-off between rapid search on nonspecific sequences and fast binding at the specific sequence.

http://www.sciencemag.org/content/336/6088/1595.full

Wednesday, June 13, 2012

Why day dreaming makes you smarter and more creative?

If you see me staring at a paper for too long, would you please nudge me out of my daydream? Being almost a matchless daydreamer myself, I really do want to belive this article. But I completely disagree. Daydreaming is definitely not working its magic on me no matter what scientists like to believe. I am getting dumber by the day-quote n quote maryem hussein.
 http://www.newyorker.com/online/blogs/frontal-cortex/2012/06/the-virtues-of-daydreaming.html

Friday, May 4, 2012

Gene Expression by Remote Control

Radio-Wave Heating of Iron Oxide Nanoparticles Can Regulate Plasma Glucose in Mice

Medical applications of nanotechnology typically focus on drug delivery and biosensors. Here, we combine nanotechnology and bioengineering to demonstrate that nanoparticles can be used to remotely regulate protein production in vivo. We decorated a modified temperature-sensitive channel, TRPV1, with antibody-coated iron oxide nanoparticles that are heated in a low-frequency magnetic field. When local temperature rises, TRPV1 gates calcium to stimulate synthesis and release of bioengineered insulin driven by a Ca2+-sensitive promoter. Studying tumor xenografts expressing the bioengineered insulin gene, we show that exposure to radio waves stimulates insulin release from the tumors and lowers blood glucose in mice. We further show that cells can be engineered to synthesize genetically encoded ferritin nanoparticles and inducibly release insulin. These approaches provide a platform for using nanotechnology to activate cells.