University of California

Yan Wu

Kun Zhang

Prashant G Mali

Udit Parekh

Amir Dailamy

Daniella McDonald

Dongxin Zhao

Michael Hu

This disclosure relates to methods, polynucleotides, vectors, viral particles, cells, and systems or the engineering of human tissues. One aspect of the disclosure relates to using lineage-specific miRNA binding molecules to bias tissue lineage. Another aspect of the disclosure relates to using lineage-specific transcription factor overexpression to bias tissue lineage.

Method to engineer transplantable human tissues

A guide RNA comprising: a gRNA spacer sequence at the 5′ end of the guide RNA, wherein the spacer sequence is complementary to a target gene, a scaffold sequence that binds to Cas9, and an RNA capture and sequencing domain comprising: a barcode sequence, and a primer binding sequence; nucleic acids and vectors encoding the guide RNA; cells expressing the guide RNA; and a library comprising a plurality of guide RNAs. Also disclosed are methods of introducing a genetic perturbation into a cell, methods of assessing an effect of at least one genetic perturbation on RNA expression in a cell, methods of identifying nucleic acid sequences associated with a disease state and a method of identifying candidate therapeutic agents.

Efficient genetic screening method

Understanding the complex effects of genetic perturbations on cellular state and fitness in human pluripotent stem cells (hPSCs) has been challenging using traditional pooled screening techniques which typically rely on unidimensional phenotypic readouts. Here, Applicants use barcoded open reading frame (ORF) overexpression libraries with a coupled single-cell RNA sequencing (scRNA-seq) and fitness screening approach, a technique we call SEUSS (ScalablE fUnctional Screening by Sequencing), to establish a comprehensive assaying platform. Using this system, Applicants perturbed hPSCs with a library of developmentally critical transcription factors (TFs), and assayed the impact of TF overexpression on fitness and transcriptomic cell state across multiple media conditions. Applicants further leveraged the versatility of the ORF library approach to systematically assay mutant gene libraries and also whole gene families. From the transcriptomic responses, Applicants built genetic co-perturbation networks to identify key altered gene modules. Strikingly, we found that KLF4 and SNAI2 have opposing effects on the pluripotency gene module, highlighting the power of this method to characterize the effects of genetic perturbations. From the fitness responses, Applicants identified ETV2 as a driver of reprogramming towards an endothelial-like state.

Methods for screening genetic perturbations

Growing community of inventors

La Jolla, CA, United States of America

Yan Wu