Biology subjects

Silverstein, R. A.

Publications and source records attributed to Silverstein, R. A..

2 recordsLinked to original sources

bioRxiv2022

Precise DNA Cloning via PAMless CRISPR-SpRYgests

While restriction enzymes (REs) remain the gold-standard for manipulating DNA in vitro, they have notable drawbacks including a dependence on short binding motifs that constrain their ability to cleave DNA substrates. Here we overcome limitations of REs by developing an optimized molecular workflow that leverages the PAMless nature of a CRISPR-Cas enzyme named SpRY to cleave DNA at practically any sequence. Using SpRY for DNA digests (SpRYgests), we establish a method that permits the efficient cleavage of DNA substrates at any base pair. We demonstrate the effectiveness of SpRYgests using more than 130 gRNAs, illustrating the versatility of this approach to improve the precision of and simplify several cloning workflows, including those not possible with REs. We also optimize a rapid and simple one-pot gRNA synthesis protocol, which reduces cost and makes the overall SpRYgest workflow comparable to that of RE digests. Together, SpRYgests are straightforward to implement and can be utilized to improve a variety of DNA engineering applications.

biochemistry↗

bioRxiv2021

A systematic genotype-phenotype map for missense variants in the human intellectual disability-associated gene GDI1

Next generation sequencing has become a common tool in the diagnosis of genetic diseases. However, for the vast majority of genetic variants that are discovered, a clinical interpretation is not available. Variant effect mapping allows the functional effects of many single amino acid variants to be characterized in parallel. Here, we combine multiplexed functional assays with machine learning to assess the effects of amino acid substitutions in the human intellectual disability-associated gene, GDI1. We show that the resulting variant effect map can be used to discriminate pathogenic from benign variants. Our variant effect map recovers known biochemical and structural features of GDI1 and reveals additional aspects of GDI1 function. We explore how our functional assays can aid in the interpretation of novel GDI1 variants as they are discovered, and to re-classify previously observed variants of unknown significance.

genetics↗