Opsin polypeptides and methods of use thereof
The present disclosure provides opsins, including variant opsins with increased activity and/or increased trafficking to the plasma membrane. The opsins are useful in therapeutic and screening applications, which are also provided.
1. An isolated fusion polypeptide comprising, in order from N-terminus to C-terminus:
a) an opsin polypeptide comprising an amino acid sequence having at least 90% amino acid sequence identity to the amino acid sequence set forth in SEQ ID NO:28;
b) a membrane trafficking signal comprising the amino acid sequence KSRITSEGEYIPLDQIDINV (SEQ ID NO: 10); and
c) an endoplasmic reticulum (ER) export signal comprising the amino acid sequence FCYENEV (SEQ ID NO:5).
2. The fusion polypeptide of claim 1 , wherein the polypeptide further comprises a fluorescent protein disposed between (a) and (b).
3. The fusion polypeptide of claim 1 , wherein the opsin polypeptide comprises an amino acid sequence having at least 95% amino acid sequence identity to the amino acid sequence set forth in SEQ ID NO:28.
4. The fusion polypeptide of claim 1 , wherein the opsin polypeptide comprises an amino acid sequence having at least 98% amino acid sequence identity to the amino acid sequence set forth in SEQ ID NO:28.