Sindbis virus: an efficient, broad host range vector for gene expression in animal cells.

Area of Science:

• Virology
• Molecular Biology
• Biotechnology

Background:

• Sindbis virus is an enveloped virus with a single-stranded RNA genome.
• Gene expression systems are crucial for producing proteins in various cell types.

Purpose of the Study:

• To engineer Sindbis virus vectors for expressing the bacterial chloramphenicol acetyltransferase (CAT) protein.
• To evaluate the efficiency and characteristics of these vectors in insect, avian, and mammalian cells.

Main Methods:

• Sindbis virus was engineered to express the CAT gene.
• Self-replicating vectors were utilized for gene expression.
• Temperature-sensitive mutations were introduced to control gene expression.
• Infectious particles were generated using a Sindbis helper virus.

Main Results:

• Efficient and rapid expression of CAT polypeptides (up to 10^8 per cell in 16-20 hours) was achieved.
• Temperature-sensitive expression was successfully implemented.
• Vector RNAs were packaged into infectious particles and remained stable for at least seven infection cycles.
• A significant 10^3-fold increase in CAT expression was observed despite extensive dilution.

Conclusions:

• Engineered Sindbis virus vectors provide a powerful tool for high-level gene product expression.
• These vectors demonstrate broad applicability across insect, avian, and mammalian cell cultures.
• The developed system offers rapid, controllable, and stable protein production for biotechnological applications.