Emily P. Bentley

Emily P. Bentley is a Blog Writer at Addgene. She earned her PhD in molecular biology and biophysics from Scripps Research, and she loves supporting open science and learning about new research.

Blog articles by Emily P. Bentley

A cartoon showing a simplified Cas9 and gRNA binding to DNA. The 3’ end of the gRNA is the scaffold sequence, bound by Cas9, where some DNA substitution is tolerated. The 20 bases on the 5’ end of the gRNA are the spacer sequence, which hybridizes with the genomic DNA, base pairing to the target strand.   The non-target strand of genomic DNA includes the same sequence as the spacer. The PAM consists of the three bases immediately 3’ of this spacer-matching sequence.  Within the gRNA spacer, the 3’ half is the seed sequence, where no DNA substitution is tolerated. The 5’ half, also the 5’ end of the entire gRNA, is the tail sequence, where DNA substitution is tolerated.
A cartoon of four cells, all carrying a different plasmid. Each cell glows a different color, matching the plasmid it carries.
A smiling Blugene holds DNA
Cartoon of CRISPR-associated transposase (CAST) integrating donor DNA into a genomic target site.
A cartoon plasmid at the center of the image has arrows leading to many possible host species: gram negative bacteria, gram positive bacteria, yeast, and mammalian cells.
A smiling Blugene holding a cartoon western blot.
The nucleobases are shown with arrows describing conversions between them. In step one, an adenosine deaminase converts adenine to hypoxanthine (the nucleobase component of inosine); this is catalyzed directly by the base editor. Next, base excision of hypoxanthine (also by the base editor) could be repaired in two different ways by the cell, shown by an arrow that splits into two outcomes. The repair pathway leading to cytosine is favored by ACBEs, while the repair pathway leading to thymine is favored by AYBEv3 + Polη.
The nucleobases are shown with arrows describing conversions between them. In step one, a cytosine deaminase converts cytosine to uracil; this is catalyzed directly by the base editor. Next, base excision of uracil (also by the base editor) is repaired in two different ways by the cell, shown by an arrow that splits into two outcomes. Repair in E. coli leads to adenine, while repair in mammalian cells leads to guanine.

Sharing science just got easier... Subscribe to our blog