The invention provides methods and compositions for eliciting broad immune responses. The methods employ nucleic acid vaccines that encodes highly conserved elements from a virus.

This disclosure generally relates to methods and compositions for eliciting broad and robust immune responses to a protein of interest. The methods employ both DNA and RNA-based vaccines that encode at least a portion of the protein of interest.

Provided herein are recombinant polynucleotides including a first nucleic acid sequence encoding an antigen, and a second nucleic acid sequence encoding an enzyme of an amino acid catabolic pathway. The provided recombinant polynucleotides are particularly useful for inducing long-lived immune responses having improved memory characteristics. Also provided are pharmaceutical compositions, viral particles, and host cells including the disclosed recombinant polynucleotides, and methods for using the disclosed materials.