Provided herein are bioluminescent polypeptides and compositions and methods for the assembly of a tripartite or multipartite bioluminescent complex. In particular embodiments, a bioluminescent complex is formed upon the interaction of three or more peptide and/or polypeptide components.

An isolated polynucleotide encoding a modified luciferase polypeptide and substrates. The OgLuc variant polypeptide has at least 60% amino acid sequence identity to SEQ ID NO: 1 and at least one amino acid substitution at a position corresponding to an amino acid in SEQ ID NO: 1. The OgLuc variant polypeptide has at least one of enhanced luminescence, enhanced signal stability, and enhanced protein stability relative to the corresponding polypeptide of the wild-type Oplophorus luciferase.

The present disclosure provides a degron comprising an amino acid sequence having at least 70% sequence identity to an amino acid sequence as set forth in SEQ ID NO: 1 for regulating the expression of a protein. The present disclosure also provides a fusion protein comprising a polypeptide of interest and the degron. Further, the present disclosure relates to a method of producing the fusion protein and a method of regulating the expression of a polypeptide of interest.

A platform is described that enables multiplexed, noninvasive, and site-specific monitoring of brain gene expression through a class of engineered reporters, referred to herein as Released Markers of Activity (RMAs). Instead of detecting gene expression in the less accessible brain, RMA reporters exit the brain into the blood, where they can be measured with biochemical techniques. When placed under a promoter upregulated by neuronal activity, RMAs may be used to measure neuronal activity in specific brain regions with a simple blood draw. As discussed herein, the present approaches provide a noninvasive paradigm for repeatable and multiplexed monitoring of gene expression in an intact brain with sensitivity that is currently unavailable through other noninvasive gene expression reporter systems.

Described herein are compositions and methods for bioluminescent analyte detection. In some embodiments, a recombinant bioluminescent polypeptide sensor is disclosed comprising a luminescent signaling domain, an analyte binding domain, and one or more peptide linkers, wherein the luminescent signaling domain is oriented in relation to the analyte binding domain such that binding of an analyte to the analyte binding domain induces a conformational change in the luminescent signaling domain to generate a luminescent signal.

An isolated polynucleotide encoding a modified luciferase polypeptide and substrates. The OgLuc variant polypeptide has at least 60% amino acid sequence identity to SEQ ID NO: 1 and at least one amino acid substitution at a position corresponding to an amino acid in SEQ ID NO: 1. The OgLuc variant polypeptide has at least one of enhanced luminescence, enhanced signal stability, and enhanced protein stability relative to the corresponding polypeptide of the wild-type Oplophorus luciferase.

Methods and compositions comprising recombinant fusion polypeptides that are engineered to allow for heterologous cargo secretion from a Bacteroides cell, into an extracellular environment are provided. Provided methods and compositions include recombinant fusion polypeptides comprising a secretion domain and a heterologous cargo domain. Methods and compositions for using said recombinant fusion polypeptides, e.g., for the treatment of a disease and/or disorder, are also provided.

Provided are compositions and methods for introducing proteins into cells. The compositions and methods relate to introducing a foreign protein as an engineered component of a paramyxovirus virus like particle (VLP). The compositions and methods pertain to modified VLPs that contain a contiguous recombinant polypeptide comprising i) all or a segment of a C-terminal domain of a paramyxovirus nucleocapsid protein and ii) a polypeptide sequence of a distinct protein that is an enzyme such as a recombinase.