Abstract: As demonstrated herein, when composite transcription factor binding sites do not function synergistically, mammalian promoters can be constructed according to simple design rules. Host-cell transcriptional machinery components were analyzed in silico to identify transcription factors with desired expression dynamics. Cognate binding sites were then comprehensively tested in homotypic and heterotypic architectures to assess modularity and determine the transcriptional activity exhibited by a single copy of each site. When elements were specifically selected to prevent combinatorial interactions, heterotypic promoter activities could be accurately modeled simply as a function of constituent binding site copy numbers. As binding site order, spacing, and orientation had minimal effect on promoter activity, blocks could be optimally combined and arranged in silico according to context-specific design-criteria.

Abstract: Simplified models of gene regulation are a fundamental requirement for mammalian synthetic biology. However, at the transcriptional level this has been impeded by the complex design rules governing promoter activity dynamics, preventing de novo-design of regulatory elements with user-defined functionalities. As demonstrated herein, when composite transcription factor binding sites do not function synergistically, mammalian promoters can be constructed according to simple design rules. Host-cell transcriptional machinery components were analyzed in silico to identify transcription factors with desired expression dynamics. Cognate binding sites were then comprehensively tested in homotypic and heterotypic architectures to assess modularity and determine the transcriptional activity exhibited by a single copy of each site.

Abstract: We discovered that recombinant antibody light chains having a murine secretory leader sequence and an SYE motif at the N-terminus are truncated during post-translational processing. This disclosure provides two protein engineering solutions: to alter the SYE amino acid sequence of the Lc N-terminus to other alternatives; or to change the secretory leader peptide sequence. We have shown that both of these solutions are effective for preventing N-terminal light chain truncation.

Abstract: We discovered that recombinant antibody light chains having a murine secretory leader sequence and an SYE motif at the N-terminus are truncated during post-translational processing. This disclosure provides two protein engineering solutions: to alter the SYE amino acid sequence of the Lc N-terminus to other alternatives; or to change the secretory leader peptide sequence. We have shown that both of these solutions are effective for preventing N-terminal light chain truncation.

Abstract: Novel anti-IL-13 antigen-binding proteins such as antibodies and antigen-binding fragments thereof are provided. Methods of using the proteins to reduce IL-13 activity and to treat IL-13-associated diseases and conditions are further provided.