Relaxin-2 fusion protein analogs and methods of using same

A fusion protein comprising, from N-terminus to C-terminus,

• a first peptide;
• a linker peptide;
• and
• a second peptide,
• wherein:
• (a) the first peptide comprises an amino acid sequence that differs at 0, 1, 2, 3, 4, or 5 amino acids when compared to the amino acid sequence of SEQ ID NO:
• 7, and the second peptide comprises an amino acid sequence that differs at 0, 1, 2, 3, 4, or 5 amino acids when compared to the amino acid sequence of SEQ ID NO:
• 9;
• or
• the first peptide comprises an amino acid sequence that differs at 0, 1, 2, 3, 4, or 5 amino acids when compared to the amino acid sequence of SEQ ID NO:
• 9;
• and the second peptide comprises an amino acid sequence that differs at 0, 1, 2, 3, 4, or 5 amino acids when compared to the amino acid sequence of SEQ ID NO:
• 7;
• and
• (b) the linker peptide comprises an amino acid sequence with 12-15 amino acids, comprising 2-5 acidic amino acids and 10-13 non-acidic amino acids, wherein:
• (i) the linker peptide comprises an amino acid sequence selected from the group consisting of:
• R1R1R1R2R1R1R1R2R1R1R1R2R1;
• R1R1R1R2R1R1R1R2R1R1R1R2R1R1R1;
• R1R1R2R1R1R1R2R2R1R1R1R2R1R1;
• R1R1R1R2R2R1R1R1R2R2R1R1R1;
• and
• R1R1R2R1R2R1R1R2R1R2R1R1R1,
• wherein R1 is a non-acidic amino acid and R2 is an acidic amino acid;
• (ii) each of the acidic amino acids in the linker peptide is aspartate;
• or
• (iii) each of the acidic amino acids in the linker peptide is glutamate.