NHEJ and HDR can occur simultaneously during gene integration into the genome of Aspergillus niger

Bibliographic Details
Title: NHEJ and HDR can occur simultaneously during gene integration into the genome of Aspergillus niger
Authors: Susanne Fritsche, Aline Reinfurt, Felix Fronek, Matthias G. Steiger
Source: Fungal Biology and Biotechnology, Vol 11, Iss 1, Pp 1-9 (2024)
Publisher Information: BMC, 2024.
Publication Year: 2024
Collection: LCC:Biotechnology
Subject Terms: DNA repair, CRISPR/Cas9-mediated genome editing, DNA modification, Homology-directed repair, Non-homologous end joining, Self-replicating plasmid, Biotechnology, TP248.13-248.65
More Details: Abstract Non-homologous end joining (NHEJ) and homology-directed repair (HDR) are two mechanisms in filamentous fungi to repair DNA damages. NHEJ is the dominant response pathway to rapidly join DNA double-strand breaks, but often leads to insertions or deletions. On the other hand, HDR is more precise and utilizes a homologous DNA template to restore the damaged sequence. Both types are exploited in genetic engineering approaches ranging from knock-out mutations to precise sequence modifications. In this study, we evaluated the efficiency of an HDR based gene integration system designed for the pyrG locus of Aspergillus niger. While gene integration was achieved at a rate of 91.4%, we also discovered a mixed-type repair (MTR) mechanism with simultaneous repair of a Cas9-mediated double-strand break by both NHEJ and HDR. In 20.3% of the analyzed transformants the donor DNA was integrated by NHEJ at the 3’ end and by HDR at the 5’ end of the double-strand break. Furthermore, sequencing of the locus revealed different DNA repair mechanisms at the site of the NHEJ event. Together, the results support the applicability of the genome integration system and a novel DNA repair type with implication on the diversity of genetic modifications in filamentous fungi.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2054-3085
Relation: https://doaj.org/toc/2054-3085
DOI: 10.1186/s40694-024-00180-7
Access URL: https://doaj.org/article/52347a8ee045481ba65569f2ffe7bf83
Accession Number: edsdoj.52347a8ee045481ba65569f2ffe7bf83
Database: Directory of Open Access Journals
More Details
ISSN:20543085
DOI:10.1186/s40694-024-00180-7
Published in:Fungal Biology and Biotechnology
Language:English