As you may have surmised from the title of this article, Proteinase K (also known as protease K or endopeptidase K) shares many functional similarities to the protagonist of the iconic TV show, Breaking Bad. Much like Walter White, Proteinase K is incredibly versatile in its applications, while remaining relatively unassuming and overlooked at times. Unlike the chemistry teacher gone rogue, however, its properties can be channeled for good.
Cell proliferation assays have a wide range of applications in scientific research – from testing drug reagents to the effect of growth factors, from testing cytotoxicity to analyzing cell activity. So, what are cell proliferation assays? Cell proliferation assays typically detect changes in the number of cells in a division or changes in a cell population.
The interest in using primary cells for cell-biology research has gained prominence in recent years due to factors such as cell line contamination (Kaur G, 2012). What made primary cells lose their popularity in the first place is partly due to the rigorous and arduous process associated with primary-cell cultivation. So why is primary-cell cultivation so difficult?
Autophagy is a catabolic process in which autophagic lysosomes degrade most cytoplasmic contents. Autophagy is usually activated in the absence of nutrients and is associated with many physiological and pathological processes, including growth, differentiation, neurodegenerative diseases, infections and tumors. Light chain 3 (LC3) is a widely recognized autophagy marker. There are three isoforms of the LC3 protein (LC3A, LC3B, and LC3C) in mammals. They undergo post-translational modifications during autophagy. The LC3 protein is first cleaved by Atg4 at its carboxy terminus immediately after synthesis to produce LC3-I, which is localized in the cytoplasm. During autophagy, LC3-I is modified and processed by a ubiquitin-like system including Atg7 and Atg3 to produce LC3-II with a molecular weight of 14 kD and localized to autophagosomes. The magnitude of the LC3-II/I ratio can be used to assess the level of autophagy.
Although exosomes were discovered over five decades ago, interest among the scientific community didn’t pique until much later. Specifically, in the last ten years, the number of annual publications about exosomes have almost increased by tenfold (from 1,570 published papers in 2007 to 14,000 in 2017). But what exactly are exosomes and what justifies the frenzy?