Tanner Wiegand

Tanner Wiegand is an Adjunct Associate Research Scientist in the Department of Biochemistry and Molecular Biophysics at Columbia University. His research integrates molecular biology, CRISPR biology, virology, and immunology to investigate the evolutionary origins and mechanistic diversity of prokaryotic immune systems. Wiegand has made significant contributions to the structural and functional characterization of CRISPR–Cas systems, most recently demonstrating that exapted CRISPR–Cas12f homologues drive RNA-guided transcription, and resolving the structural basis of RNA-guided transcription by a dCas12f–σE–RNAP complex (Nature, 2026). His work also extends to antiviral reverse transcriptases, where he identified protein-primed homopolymer synthesis and proposed an evolutionary link to telomerase (Nature, 2025). Additional research includes the coordinated synthesis of double-stranded DNA by dual reverse transcriptase immune systems and the post-translational modification of toxins by type III-Bv CRISPR complexes. His findings have broad implications for genome editing, gene expression regulation, and the evolutionary biology of host–pathogen interactions.