Further insights into the role of NIN-LIKE PROTEIN 7 (NLP7) in root cap cell release.

The root cap protects the root from environmental stress and senses gravity. Cells of the last layer of the root cap are shed in a developmentally programmed process. We previously showed that the transcription factor NIN-LIKE PROTEIN7 (NLP7) regulates root cap cell release likely through regulation of CELLULASE5 (CEL5). Here we provide a supplement to that work. We hypothesized that the nlp7 mutant has defects in additional root cap functions. We find that neither gravity sensing nor expression of a root cap cell identity marker is altered in nlp7 but that expression of another cellulase, CEL3, is upregulated. We conclude that NLP7 control of root cap cell release is largely independent of gravity sensing and root cap cell identity.