Fusion protein

Translation of this fusion gene results in a single or multiple polypeptides with functional properties derived from each of the original proteins.

Naturally occurring fusion proteins are commonly found in cancer cells, where they may function as oncoproteins.

However, other fusion proteins, especially those that occur naturally, combine only portions of coding sequences and therefore do not maintain the original functions of the parental genes that formed them.

For partial gene fusions, the shuffling of different active sites and binding domains have the potential to result in new proteins with novel functions.

The most commonly used PCFP is the Kaede fluorescent tag, but the development of Kikume green-red (KikGR) in 2005 offers a brighter signal and more efficient photoconversion.

The advantage of using PCFP fluorescent tags is the ability to track the interaction of overlapping biochemical pathways in real time.

For example, human constant domains can be introduced, thereby eliminating most of the potentially immunogenic portions of the drug without altering its specificity for the intended therapeutic target.

Etanercept, for example, is a TNFα blocker created through the combination of a tumor necrosis factor receptor (TNFR) with the immunoglobulin G1 Fc segment.

[3] Novel recombinant technologies have made it possible to improve fusion protein design for use in fields as diverse as biodetection, paper and food industries, and biopharmaceuticals.

This provides a flexible bridge structure allowing enough space between fusion partners to ensure proper folding.

However, the N or C termini of the peptide are often crucial components in obtaining the desired folding pattern for the recombinant protein, making simple end-to-end conjoining of domains ineffective in this case.

This technique is typically regarding as more difficult to carry out than tandem fusion, due to difficulty finding an appropriate ligation site in the gene of interest.

Two major examples are: double PP2C chimera in Plasmodium falciparum (the malaria parasite), in which each PP2C module exhibits protein phosphatase 2C enzymatic activity,[7] and the dual-family immunophilins that occur in a number of unicellular organisms (such as protozoan parasites and Flavobacteria) and contain full-length cyclophilin and FKBP chaperone modules.