In Table 1, page 2 of our Bio-protocol paper www.bio-protocol.org/e3141, the reverse primer (V20-R) for colony PCR and DNA sequencing is incorrect, the correct sequence is
5’-AAGGGAACAAAAGCTGGAGC-3’.

Table 1. The primers for colony PCR and DNA sequencing

Primer	Sequence
U6Bp-FS1	5’-TCAACAAACGAACAATAGGACAC-3’
V20-R	5’-AAGGGAACAAAAGCTGGAGC-3’

And in page 6, Note of Procedure B2, " If we want to mutate a gene on the second chromosome, we should choose TH00788 (y,v; attp40{nos-Cas9}) to microinject, while a gene on the third chromosome to choose TH00787 (y,v;; attp2{nos-Cas9})" , the order of the description of two chromosome is reversed. The correct description is as below:

Note: The transgenic Cas9 flies were created through integrating nos-Cas9 plasmid (Ren et al., 2013) into attP40 landing site on the second chromosome or attP2 landing site on the third chromosome by phiC31 integrase, followed by screening for the vermillion+ marker present in the nos-Cas9 plasmid. If we want to mutate a gene on the third chromosome, we should choose TH00788 (y,v; attp40{nos-Cas9}) to microinject, while a gene on the second chromosome to choose TH00787 (y,v;; attp2{nos-Cas9}). Also, both TH00788 and TH00787 can be selected to microinject to mutate a gene on the X or the fourth chromosome. Please note that nos-Cas9 and target gene should be expressed on different chromosomes in order to separate the chromosome with Cas9 in next step.

References

Peng, P., Wang, X., Shen, D., Sun, J., Jia, Y., Xu, R., Zhu, L. and Ni, J. (2019). CRISPR-Cas9 Mediated Genome Editing in Drosophila. Bio-protocol 9(2): e3141. DOI: 10.21769/BioProtoc.3141.