Expression of Ebola glycoprotein

GP glycoprotein plays a critical role in the virulence of Ebola virus. It is usually expressed in soluble form sgp 364 amino acid residues forming a 110 kDa homodimer composed of two identical polypeptide chains held together by two parallel disulfide bridges of cysteines at 53 and 30632. The product of transcription of the gene GP is actually slightly longer than the functional GSP, which result from cleavage by furin pre-SGP produced by releasing a small strongly called Δ-peptide (peptide or Δ) O-glycosylated nonstructural protein.

However, the GP gene of the genre Ebolavirus virus contains seven consecutive adenine residues likely forming a hairpin structure or stem-loop, at which the viral polymerase patina or "stutters" (called polymerase stuttering) : approximately one in five cases, it inserts an extra adenine in the messenger RNA, which shifts to a reading frame nucleotide codon by the ribosome. The protein produced by this modified mRNA, the GP itself, is thus different from the GSP: its N-terminal 295 residues are identical, but the following 312 residues C-terminal side, are different. It follows a longer protein, total 676 residues (for a more Reston virus), cleaved by furin in a basic region to form two subunits, GP1 and GP2, held together by a disulfide bridge between Cys53 and Cys609 on GP1 to GP2. It is this which is assembled heterodimer of 450 kDa trimer on the surface of the virion lipid membrane and allows them to penetrate into the host cells to infect.

Skating on the L polymerase hairpin also produces a third glycoprotein, called SSGP whose role is not known and which is believed to be monomeric; this occurs by insertion of two extra adenine residues at the stem-loop region in the PG gene of the virus, which shifted the two nucleotides of both the reading frame of the mRNA and the ribosome leads to protein of 298 amino acid residues.

The expression of glycoproteins by several overlapping genes is characteristic for distinguishing among filoviruses, viruses and genres Ebolavirus Cuevavirus Marburgvirus of the kind, they only produce virus glycoprotein GP1,27.