The disclosure relates to a plurality of cells, compositions and methods for identifying modulators of a target protein. The cells, compositions and methods comprise a (i) a target domain gene (ii) an intracellular chimeric G-protein alpha subunit comprising an endogenous G-protein alpha subunit with a humanized C-terminus; and (iii) an inducible reporter, wherein the expression of the reporter is dependent on the activation of the target domain encoded by target domain gene, and wherein the target domain gene comprises a barcode. The disclosure further relates to a host cell comprising a plurality of exogenous landing pads integrated in the host cell's genome, wherein each exogenous landing pad is integrated at a safe harbor genome loci in the host cell's genome.

The present disclosure provides peptides that inhibit a binding interaction between a β integrin and a G protein subunit, as well as compositions, e.g., pharmaceutical compositions, particularly nanoparticle compositions, comprising the same and to methods of using the peptides to treat atherosclerosis, thrombosis, stroke, heart attack, inflammation, acute respiratory distress syndrome (ARDS), autoimmune diseases, AV Fistula for hemodialysis or organ transplantation.

Methods of treating a subject suffering from COVID-19 are provided. Aspects of the methods including administering to the subject an effective amount of an inhibitor of CCR5/CCL5 interaction, such as a CCR5 antagonist. Also provided are methods of assessing severity of a disease involving hypercytokinemia, such as COVID-19, by determining the level of CCL5/RANTES in a subject, as well as compositions for use in such methods.

A protein for visual color recognition and the like, the protein having a channel activity and including an amino acid residue different from the amino acid residue present in a first amino acid sequence represented by SEQ ID NO: 1, at a position or positions corresponding to one or two or more selections from the group consisting of the following positions in the first amino acid sequence: positions 53, 83, 87, 117, 120, 124, 137, 139, 142, 143, 146, 150, 169, 173, 177, 198, 204, 216, 217, 218, 231, 238, 245, and 247.

A protein-based probe for detecting the presence of one of two distinct states of a target membrane-associated molecule by means of polarization microscopy is disclosed. The probe contains an anchoring moiety consisting of at least one lipidated peptide and/or at least one transmembrane α-helical peptide, a peptide linker moiety having the length of at least 5 amino acids, wherein at least 50% of the amino acids forming the linker are selected from glycine, serine, and threonine, a fluorescent moiety, and an affinity binding moiety capable of binding the target membrane-associated molecule. The moieties are arranged in the order a-b-c-d or d-c-b-a in the direction from the N-terminus to the C-terminus. Methods of detecting presence or absence of the target molecule, detecting activated or inactive forms of the target molecule, and detecting the activation of the target molecule are also described.

The present application discloses in detail mutant ligands of the human G protein alpha-subunit—Gαi1—, wherein at least one amino acid residue has been replaced with alanine if the at least one amino acid residue is a non-alanine residue, or at least one amino acid residue has been replace with glycine if the at least one amino acid residue is alanine and wherein the at least one amino acid residue is comprised in a first group containing of the amino acid residues with position R32A, K54A, I55A, I56A, H57A, R176A, E245A, Y296A, T327A, N331A, V332A and D350A or is comprised in a second group containing G42A, A59G, T177A, D200A, A226G, E297A, A300G and F334A or is comprised in a third group containing V50A, A59G, R178A 30 and K180A.

The design and generation of a number of chimeric VSV-G (or VSV-G variants) proteins are used as transfer vehicles to enhance delivery of nucleic acids like plasmid DNA, single and double stranded DNA and RNA, and antisense oligonucleotides into human and animal cells. These chimeric VSV-G protein-nucleic acid transfer vehicles have widespread applications to deliver nucleic acids for exon skipping and gene delivery for gene replacement in human and animals.

The present invention relates to the field of protein expression. More specifically, the present invention provides compositions and methods for increasing the expression and signaling of proteins on cell surfaces. In particular embodiments, the present invention provides nucleic acids and amino acid sequences useful for improving/increasing protein expression on the cell surface. In several embodiments, the sequences are operably linked to the N-terminal end of the protein of interest. The nucleic acid sequence encoding the sequence tag and the protein comprise part of an expression vector. The protein is expressed with the N-terminal sequence tag. In certain embodiments, the sequences of the present invention can be used with one or more chaperone or accessory proteins. In particular embodiments, the one or more chaperone/accessory proteins are encoded by the same vector or separate vectors. In other embodiments, the chaperone/accessory proteins are encoded the same vector that encodes the protein of interest.

Resonance energy transfer (RET)- or protein-fragment complement assay (PCA)-based biosensors useful for assessing the activity of G-proteins are described. These biosensors are based on the competition between the Got subunit and a Gβγ interacting protein (βγ IP) for the binding to the Gβγ dimer. These biosensors comprises (1) a βγ IP and (2) a Gβ or Gγ protein; a GPCR; or a plasma membrane targeting domain, fused to suitable RET or PCA tags. Methods using such biosensors for different applications, including the identification of agents that modulates G-protein activity or for the characterization of GPCR signaling/regulation, such as G-protein preferences and activation profiles of GPCRs, are also described.

The present disclosure provides peptides and constructs that inhibit mitochondrial fission, and compositions comprising the peptides or constructs. The present disclosure provides methods of reducing abnormal mitochondrial fission in a cell. Also provided are methods for designing and validating mitochondrial fission inhibitor constructs and peptides, including but not limited to, evaluating the effects of the constructs and peptides on binding of dynamin-1-related protein (Drp1) GTPase activity, Drp1 to mitochondrial fission 1 protein (Fis1), reduction of mitochondrial damage, reduction in cell death, inhibition of mitochondrial fragmentation in a cell under pathological conditions, and reduced loss of neurites in primary dopaminergic neurons in a Parkinsonism cell culture.