What are the most cited chemical probes?
At the beginning of the summer, we spoke on our blog about having new data on the chemical probes market following the expansion of our platform, and over the summer the team at CiteAb has been looking into this data in depth.
The dataset has increased in size in this time, covering over 35,000 citations against around 16,000 product groups and over 100,000 products – giving really nice insight into the market.
Today our product manager Rebecca is going to give a few highlights from this data – focusing on the chemical probes that are the most cited in academic literature.
“A chemical probe is generally a small molecule that is used throughout research to study certain molecular targets in cells or organisms,” Rebecca explains. “Chemical probes include inhibitors and activators that bind to specific protein targets, that can be used to reveal the function(s) of specific proteins in cellular processes. But they can also include related tools such as cellular stains.”
So which chemical probe is most cited? Rebecca tells us: “The most cited product is propidium iodide (PI), a fluorescent dye able to bind to DNA, and effectively stain cells. As it is unable to pass through the membrane of live cells it can be used for cell viability analysis, enabling the distinction between necrotic, apoptotic and live cells. Therefore, PI is very commonly used in flow cytometry immunofluorescence, and confocal microscopy.”
It is not a surprise to see that multiple chemical probes in the top 10 have been highly cited in cancer research. For example, rapamycin (second highest cited) has antiproliferative effects on cancer cells, forming a complex with FKBP12, inhibiting mTOR which affects the phosphoinositol 3-kinase/Akt signaling pathway leading to cell cycle arrest in G1.
The third most cited product, U0126, inhibits multiple proteins, but is most selective against MEK1 and MEK2, and has been used to study ERK2 function. Rebecca adds: “Many cancers have been found to have a defect in the MAP/ERK pathway that allow the uncontrolled growth of the cancer, so MEK inhibitors are believed to be important in the development of future cancer treating drugs.”
The full top ten chemical probes are responsible for 16.36 per cent of all of our chemical probe citations, and come from twelve different companies. The largest supplier is Sigma-Aldrich, responsible for 59.42 per cent of citations in the top ten, and Millipore, responsible for 23.16 per cent. Parent company MilliporeSigma therefore claims a lions share of 82.58 per cent of the citations for top ten products.
To view the full list of the top 10 most cited chemical probes sign up below. If you are interested in our full and detailed dataset on chemical probes please get in touch.
– Matt and the CiteAb team