Evolutionary history of cotranscriptional editing in the paramyxoviral phosphoprotein gene

Area of Science:

• Virology
• Molecular Biology
• Evolutionary Biology

Background:

• Paramyxoviruses utilize a single phosphoprotein gene to produce multiple proteins, including P, V, and W.
• These proteins arise from a process called transcriptional slippage, which inserts non-templated guanosine nucleosides into mRNA.
• This editing is crucial for generating the essential P protein, a component of the viral RNA polymerase.

Purpose of the Study:

• To review the nature of guanosine insertion probability distributions in paramyxoviruses.
• To reconstruct the evolutionary history of cotranscriptional editing within the paramyxovirus family.
• To examine the physical mechanisms underlying RNA editing via polymerase slippage.

Main Methods:

• Analysis of mRNA sequencing data to infer guanosine insertion probability distributions.
• Bioinformatic reconstruction of evolutionary events related to RNA editing.
• Review of existing literature on paramyxovirus RNA editing mechanisms.

Main Results:

• The system has switched between P and V default expression modes four times.
• Complete loss of the RNA editing system occurred twice.
• The V protein's zinc finger domain was deleted/mutated twice, and the W protein evolved new functions thrice.

Conclusions:

• Cotranscriptional editing in paramyxoviruses exhibits diverse evolutionary trajectories.
• The P and V protein expression balance is dynamically regulated through editing.
• Understanding these editing mechanisms provides insights into viral evolution and protein diversification.