Gene transferability and sociality do not correlate with gene connectivity

Area of Science:

• Genomics
• Evolutionary Biology
• Microbiology

Background:

• Gene connectivity, the number of interactions a gene product has, is a fundamental genetic characteristic.
• The complexity hypothesis posits that genes with high horizontal gene transfer rates in prokaryotes exhibit lower connectivity.

Purpose of the Study:

• To investigate the relationship between horizontal gene transfer and gene connectivity in prokaryotes.
• To examine factors influencing gene connectivity, including gene location (chromosomal vs. plasmid) and plasmid characteristics.

Main Methods:

• Comparative analysis of gene connectivity across 134 prokaryotic species.
• Examination of chromosomal and plasmid gene interactions.
• Correlation analysis of gene connectivity with horizontal gene transfer, plasmid mobility, and gene sociality.

Main Results:

• Plasmid-borne genes demonstrated significantly lower connectivity compared to chromosomal genes.
• No correlation was found between the connectivity of plasmid genes and their mobility.
• Gene sociality (cooperative or private) did not correlate with gene connectivity.

Conclusions:

• Horizontal gene transfer does not appear to reduce gene connectivity in prokaryotes as predicted by the complexity hypothesis.
• Gene location (plasmid vs. chromosome) is a significant determinant of gene connectivity.
• Plasmid mobility and gene sociality are not primary drivers of gene connectivity variations in prokaryotes.