Structural polyprotein Protein, Sindbis virus (Cell-Free, His, SUMO)

The structural polyprotein directs the assembly of icosahedral capsids (T=4 symmetry), housing 240 capsid protein copies and 80 E1-E2 spike heterodimers in the lipid membrane. It binds viral RNA, aids in release post-translation, and has protease activity to form icosahedral core particles. Structural polyprotein Protein, Sindbis virus (Cell-Free, His, SUMO) is the recombinant Virus-derived Structural polyprotein protein, expressed by E. coli Cell-free , with N-10*His, N-SUMO labeled tag. The total length of Structural polyprotein Protein, Sindbis virus (Cell-Free, His, SUMO) is 439 a.a., with molecular weight of 65.9 kDa.

The Structural polyprotein Protein orchestrates the formation of an icosahedral capsid with T=4 symmetry, comprising 240 copies of the capsid protein enveloped by a lipid membrane, and featuring 80 spikes composed of E1-E2 heterodimeric trimers. This protein binds to the viral RNA genome adjacent to a ribosome binding site, facilitating viral genome translation post-release. With protease activity causing autocatalytic cleavage, the capsid protein transiently associates with ribosomes, rapidly assembling into icosahedral core particles after self-cleavage. The resulting nucleocapsid associates with the cytoplasmic domain of the spike glycoprotein E2 at the cell membrane, driving budding and mature virion formation. In infection, new virions attach to target cells, undergo clathrin-mediated endocytosis, and fuse with the host endosomal membrane, releasing the nucleocapsid into the cytoplasm. This initiates an uncoating event crucial for genomic RNA accessibility, possibly triggered by capsid protein interaction with ribosomes. The protein specifically inhibits interleukin-1 receptor-associated kinase 1/IRAK1-dependent signaling during viral entry, evading innate immune detection before viral gene expression. Additionally, it provides a signal sequence for translocating the precursor of protein E3/E2 to the host endoplasmic reticulum. Furin-cleaved E3, associated with spike glycoprotein E1, mediates pH protection during transport through the secretory pathway, gradually releasing in the extracellular space after virion release from the host cell.

Virus

E. coli Cell-free

N-10*His;N-SUMO

P03316 (Y807-R1245)

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YEHATTVPNVPQIPYKALVERAGYAPLNLEITVMSSEVLPSTNQEYITCKFTTVVPSPKIKCCGSLECQPAAHADYTCKVFGGVYPFMWGGAQCFCDSENSQMSEAYVELSADCASDHAQAIKVHTAAMKVGLRIVYGNTTSFLDVYVNGVTPGTSKDLKVIAGPISASFTPFDHKVVIHRGLVYNYDFPEYGAMKPGAFGDIQATSLTSKDLIASTDIRLLKPSAKNVHVPYTQASSGFEMWKNNSGRPLQETAPFGCKIAVNPLRAVDCSYGNIPISIDIPNAAFIRTSDAPLVSTVKCEVSECTYSADFGGMATLQYVSDREGQCPVHSHSSTATLQESTVHVLEKGAVTVHFSTASPQANFIVSLCGKKTTCNAECKPPADHIVSTPHKNDQEFQAAISKTSWSWLFALFGGASSLLIIGLMIFACSMMLTSTRR

65.9 kDa

Greater than 90% as determined by reducing SDS-PAGE.

<1 EU/μg, determined by LAL method.