In silico versus in vitro #2

There is no adequate excuse for not keeping up with regular blog entries. Arguably, working in the lab from 9 a.m. to 8.30 p.m. – in a mad rush to collect some data before the lab meeting next week – in addition to preparing for seminars and the imminent badminton match against Oxford help to explain the recent scarcity of cell/science-related news. Especially when a statistically significant number of experiments in the lab end up looking like this Western blot on the right (image copied from here):

However, on the more positive side of things I have learnt a couple more cell/molecular biology techniques since I started working in the lab several weeks ago. Beforehand I only knew about the theory of these methods and how to interpret results, but not how to actually carry out the experiments:

• Immunohistochemistry (IHC): this technique allows specific staining of (mouse) tissue sections. One can, for example, compare specific markers of proliferation or cell death in healthy skin versus tumours/melanoma lesions.
• Quantitative reverse transcription polymerase chain reaction (qRT-PCR): this allows analysis of gene expression (specifically transcription) in tumour samples or cultured cells under different conditions. For example, I have been comparing the expression of certain transcription factors in cells that are sensitive to a melanoma drug versus cells that have acquired resistance to that drug.
• Cell cycle analysis by fluorescence-activated cell sorting (FACS): lastly, this method is used to quantify the proportion of cells within a population that are actively dividing, non-dividing or dead. To do this, the amount of DNA in each cell is stained using a dye such as propidium iodide, or newly synthesised DNA can be labelled using bromodeoxyuridine.

Now on to the simple task of analysing the data…