Main Text
(Plant Communications 1, 100016-1–18; January 2020)
In the NRC subsection of this review, there are several sentences with reference errors or misleading wording. These sentences are contained within the paragraph “There are four subclades in the NRC family, namely NRC1, NRC2, NRC3, and NRC4. NRC1 was first observed in a Solanum lycopersicum screen…. The complexity of the NRCs will be better explained upon further biochemical and genetic analysis.” The authors of this review request the publication of the corrected paragraph as follows:
“There are four subclades in the NRC family, namely NRC1, NRC2, NRC3, and NRC4. NRC1 was first identified in a Solanum lycopersicum virus induced gene silencing (VIGS) screen for genes required for Cf-4 function (Gabriëls et al., 2006). When VIGS was performed with an NRC1 gene fragment from S. lycopersicum to silence NRC1 in N. benthamiana (Gabriëls et al., 2006, Gabriëls et al., 2007), immune response triggered by R proteins Pto, Cf4, Cf-9, Ve1, Rx, LeEix2, and Mi were attenuated (Gabriëls et al., 2006, Gabriëls et al., 2007). However, more recent studies found that N. benthamiana does not have an NRC1 ortholog, and instead carries a number of NRC1 paralogs, which were termed NRC2a, NRC2b, NRC2c, NRC3, and NRC4 (Wu et al., 2016, Wu et al., 2017). When the initial gene fragment from the VIGS experiments was analyzed, it was predicted that the fragment would likely have targeted the N. benthamiana genes NRC2a, NRC2b, NRC2c, and NRC3 (Wu et al., 2016). NRC2a, NRC2b, and NRC3 are required for Prf, R8, and Pto-mediated HR, and are weakly involved in Cf4-mediated HR, contributing redundantly to Rx-mediated immunity alongside NRC4 (Wu et al., 2016, Wu et al., 2017). On the other hand, NRC4 was found to be required for HR mediated by Rpi-blb2, R1, and Mi-1.2 in N. benthamiana (Wu et al., 2017). NRC4's p-loop is essential in the N. benthamiana HR responses, whereas the CC domain was sufficient for immunity (Wu et al., 2017), as defense could be enhanced in S. lycopersicum by truncating NRC4 by 67 amino acids using CRISPR/Cas9 editing (Leibman-Markus et al., 2018a, Leibman-Markus et al., 2018b). Triple silencing of NRC2, NRC3, and NRC4 in N. benthamiana lead to disruption of Rx, R1, R8, Mi-1.2, Sw5b, and Bs2-mediated HR (Wu et al., 2017). Thus, the NRC family members seem to have evolved to serve redundant convergent helper roles for a large repertoire of sensor NLRs recognizing diverse effectors from viruses, bacteria, oomycetes, nematodes, and insects. Future biochemical analysis will be needed to reveal how these helper NLRs work alongside other proteins to signal defense responses in Solanaceae.”
The authors apologize for not detecting these errors prior to publication and for any inconvenience this may have caused. The authors also thank Dr. Sophien Kamoun for pointing out some of the errors.
Footnotes
Published by the Plant Communications Shanghai Editorial Office in association with Cell Press, an imprint of Elsevier Inc., on behalf of CSPB and IPPE, CAS.