In our recently published article [1], we noticed incorrect citations, typing errors and improper punctuations. Thus, “pCBS-Pfset2” and “pGFP-CBS-Pfset2” were both used in our original article, but in Fig. 1a the name “pCBS-Pfset2” was wrongly cited; this should read “pGFP-CBS-Pfset2”. The correct version of Fig. 1 can be found below. In other sections, “pCBS-Pfset2” was cited correctly. In the “Plasmid constructs” section of the original article, “pGCBS-Pfset2” should read “pGFP-CBS-Pfset2”, and “pARM-Pfset2”, the name of the rescue plasmid for Pfset2 gene disruption, should read “pARM-SET2ko”. We would like to apologize for the errors and for any inconvenience this may have caused.
Fig. 1.
Redesigned marker-free CRISPR/Cas9-mediated deletion of the Pfset2 locus. a Construct used for Pfset2 gene disruption. Introns 1 to 4 of the Pfset2 locus are represented as gray boxes. pGFP-CBS-Pfset2 was designed to induce a double-strand break (DSB) near the 5' end of intron 2. The Avi-tag between the homology arms was added to detect donor integration in the design of the PCR primers. Pf U6 5’, Pf U6 spliceosomal RNA promoter region; Pf CAM5’, Pf calmodulin promoter region; Pf Hsp86 5’, Pf heat shock protein 86 promoter region; AmpR, ampicillin resistance gene; ori, replication origin; ko, knockout. The positions and directions of the primers P1 to P4 are indicated by the small black arrows. b PCR analysis of the parasite populations obtained after transfection. WT, wild-type; SET2Δ, Pfset2 knockout; d31, d38, d47, and d61, days 31, 38, 47, and 61 after transfection, respectively; FACS: fluorescence-activated cell sorting. c Laser confocal microscopy of the parasites expressing the GFP protein. d DNA sequencing confirmed a 1.5-kb deletion in the Pfset2 gene. The top panel shows the partial nucleotide sequences of the left and right arms from the parental strain. The bottom panel shows the 48-bp DNA insert between the left and right arms
Footnotes
The online version of the original article can be found under doi:10.1186/s13071-016-1487-4.
Contributor Information
Li Qin, Email: qin_li@gibh.ac.cn.
Xiaoping Chen, Email: chen_xiaoping@gibh.ac.cn.
References
- 1.Lu J, Tong Y, Pan J, Yang Y, Liu Q, Tan X, et al. A redesigned CRISPR/Cas9 system for marker-free genome editing in Plasmodium falciparum. Parasite Vectors. 2016;9:198. doi: 10.1186/s13071-016-1487-4. [DOI] [PMC free article] [PubMed] [Google Scholar]