Viral Infection or IFN-α Alters Mitotic Spindle Orientation by Modulating Pericentrin Levels.

Area of Science:

• Neuroscience
• Virology
• Genetics

Background:

• Congenital microcephaly is a condition where the head is smaller than normal, often occurring during prenatal development.
• Zika virus (ZIKV) infection is a known cause of congenital microcephaly.
• Majewski osteodysplastic primordial dwarfism type II (MOPDII) is a genetic disorder also associated with microcephaly and reduced levels of pericentrin (PCNT).

Purpose of the Study:

• To investigate the role of pericentrin (PCNT) in microcephaly.
• To explore the connection between viral infections, interferon-alpha (IFN-α) response, and microcephaly.
• To identify a common mechanism underlying microcephaly in different conditions.

Main Methods:

• Cell culture experiments were performed.
• Cells were infected with various viruses, including ZIKV, dengue virus, cytomegalovirus, influenza A virus, and hepatitis B virus.
• Cells were treated with interferon-alpha (IFN-α).
• Levels of pericentrin (PCNT) at the mitotic spindle poles were assessed.
• Mitotic spindle orientation was analyzed.

Main Results:

• Both viral infections and IFN-α exposure led to a reduction in PCNT levels at the mitotic spindle poles.
• Viral infections and IFN-α treatment caused mitotic spindle misorientation.
• This effect was observed across a diverse range of viruses.

Conclusions:

• A shared molecular mechanism involving PCNT reduction and mitotic spindle misorientation contributes to microcephaly.
• The host's antiviral response, specifically IFN-α, plays a role in inducing microcephaly during viral infections.
• This mechanism links microcephaly observed in viral infections, MOPDII, and antiviral responses.