GFP and Determination of Transfection Efficiency Green Fluorescent Protein (GFP) is a 26.9 kDa protein that fluoresces bright green when exposed to blue or ultraviolet light. GFP was first identified as a protein and extracted from the Aequorea victoria  jellyfish in 1962 by Osamu Shimomura, et al.  The GFP protein was first cloned in 1992 and it was soon confirmed that GFP protein expressed in other organisms generates fluorescence. An area within a cell or tissue is briefly illuminated, causing the GFP protein to fluoresce, allowing GFP-tagged proteins to be identified. In 2008, Osamu Shimomura, Marty Chalfie, and [...]

Autophagy is a normal process by which eukaryotic cells break down out-dated and damaged cellular organelles and proteins to be replaced with new ones. It is also a survival mechanism providing cells with energy and substrates for cellular processes in times of stress and starvation. Autophagy is a multi-step process involving initiation, formation of autophagosomes (vesicles that capture and deliver cytoplasmic material to lysosomes for digestion), maturation, and degradation (Figure 1.) […]

Caspase-3 belongs to a family of evolutionally conserved cysteine proteases that play a key role in regulating programmed cell death, or apoptosis, a normal process required for maintenance of tissue homeostasis and the regulation of physiological functions1. The two main apoptosis activation pathways are the extrinsic and the intrinsic pathways.  The extrinsic pathway is activated by the binding of ligands (including TNFα, FasL, and TRAIL) to cell-surface receptors. The intrinsic, or mitochondrial, pathway is typically activated in response to DNA or cellular damage. The convergence of the extrinsic and intrinsic pathways occurs at the proteolytic activation of caspase-34. Once caspase-3 is [...]