GFP vs YFP
GFP and YFP are two very different fluorescent proteins derived from Aequorea victoria , a jellyfish. Many marine organisms have similar green fluorescent proteins, but GFP refers to a protein which was originally isolated from this particular jellyfish. YFP is a genetic mutant of the GFP.
GFP
GFP stands for Green Fluorescent Protein. The main characteristic of Green Fluorescent Protein is that when it is exposed to blue ultraviolet light, it exhibits a green fluorescence.GFP is made of 238 amino acids. Fluorescent proteins have two peaks, an excitation peak and an emission peak.GFP exhibits an excitation peak at 395nm wavelengths, and its emission peak is 509nm wavelengths. 509nm in the visible spectrum is the lower green part. The quantum yield or QY of green fluorescent protein is 0.79.quantum yield refers to the number of times an event occurs when a radiation –induced process takes place per photon. In this case the “event” refers to the emission of photons.
GFP has been very useful in molecular and cell biology. It is used as a “reporter of expression”. Reporter genes are genes which are used by scientists and researchers to attach to another gene which they are studying. They help in measuring and indicating whether a gene has been expressed by an organism population or cell. They are also used as biosensors.
For the discovery of GFP and its development Roger Tsien, Osamu Shimomura and Martin Chalfie received the 2008 Nobel Prize.
YFP
YFP stands for Yellow Fluorescent Protein. It is a mutant of the originally derived Green Fluorescent Protein, from the jellyfish Aequorea Victoria. YPF also has two different peaks; its emission peak is 527nm and its excitation peak is 515 nm. The uses of YFP are similar or same to GFP in molecular biology.
YFP has 3 improved versions; Ypet, Citrine and Venus. The special characteristics of these improved versions are that they have chloride sensitivity which is reduced and it has a faster maturation; they have increased brightness due to the quantum yield. They are used typically as acceptors for FRET sensors. FRET stands for Fluorescence resonance energy transfer. They are also called RET or EET, resonance energy transfer and electronic energy transfer respectively. It is a mechanism which describes the energy transfer between 2 chromophores.
Summary
- GFP stands for Green Fluorescent Protein, which was originally derived from the jellyfish Aequorea Victoria. YFP stands for Yellow Fluorescent Protein. It is a mutant of the originally derived Green Fluorescent Protein from the jellyfish Aequorea Victoria.
- GFP exhibits an excitation peak at 395nm wavelengths,s and its emission peak is 509nm wavelengths. YFP emission peak is 527nm and excitation peak is 515 nm.
- GFP has been very useful in molecular and cell biology. It is used as a “reporter of expression”; YFP are used typically as acceptors for FRET sensors.
- YFP has three improved versions Ypet, Citrine and Venus.