Open AccessOca2targeting using CRISPR/Cas9 in the Malawi cichlidAstatotilapia calliptera
Author(s) -
Bethan Clark,
Joel Elkin,
Aleksandra Marconi,
George F. Turner,
Alan Smith,
Domino A. Joyce,
Eric A. Miska,
Scott A. Juntti,
M. Emília Santos
Publication year - 2022
Publication title -
royal society open science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.84
H-Index - 51
ISSN - 2054-5703
DOI - 10.1098/rsos.220077
Subject(s) - biology , evolutionary biology , genetics , crispr , gene , genome , genome editing , cichlid , computational biology , fishery , fish <actinopterygii>
Identifying genetic loci underlying trait variation provides insights into the mechanisms of diversification, but demonstrating causality and characterizing the role of genetic loci requires testing candidate gene function, often in non-model species. Here we establish CRISPR/Cas9 editing inAstatotilapia calliptera , a generalist cichlid of the remarkably diverse Lake Malawi radiation. By targeting the geneoca2 required for melanin synthesis in other vertebrate species, we show efficient editing and germline transmission. Gene edits include indels in the coding region, probably a result of non-homologous end joining, and a large deletion in the 3′ untranslated region due to homology-directed repair. We find thatoca2 knock-outA. calliptera lack melanin, which may be useful for developmental imaging in embryos and studying colour pattern formation in adults. AsA. calliptera resembles the presumed generalist ancestor of the Lake Malawi cichlids radiation, establishing genome editing in this species will facilitate investigating speciation, adaptation and trait diversification in this textbook radiation.