RT Journal Article
SR Electronic
T1 The NIN-LIKE PROTEIN 7 (NLP7) transcription factor modulates auxin pathways to regulate root cap development
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2022.03.12.484102
DO 10.1101/2022.03.12.484102
A1 Narender Kumar
A1 Chloe Caldwell
A1 Anjali S. Iyer-Pascuzzi
YR 2022
UL http://biorxiv.org/content/early/2022/03/13/2022.03.12.484102.abstract
AB The root cap surrounds the root tip and promotes root growth by protecting the root apical meristem, influencing root branching, and sensing environmental signals like nitrate. The root cap maintains a constant size through the coordination of cell production in the root meristem with cell release at the tip of the root, a process that requires an auxin minima in the last layer of the root cap. To perform its functions, the root cap must maintain a constant size and synchronize external cues with development, but mechanisms underlying such coordination are not well understood. Mutations in the NIN LIKE PROTEIN 7 (NLP7) transcription factor, a master regulator of nitrate signaling, lead to defects in root cap cell release and cell production. Nitrate impacts root development through crosstalk with auxin. Therefore, we hypothesized that NLP7 regulates root cap cell release and cell production by modulating auxin pathways. Here we show that mutations in NLP7 abolish the auxin minima required for root cap cell release and alter root cap expression levels of the auxin carriers PIN-LIKES 3 (PILS3) and PIN-FORMED 7 (PIN7). We find that NLP7 is required for proper root cap cell production and differentiation and for expression of transcription factors that regulate these processes. Nitrate deficiency impacts auxin pathways in the last layer of the root cap, and this is mediated in part by NLP7. Together, our data suggest that NLP7 integrates nitrate signaling with auxin pathways to optimize root cap development in response to external nitrate cues.One sentence summary The nitrate master regulator NLP7 controls root cap development through auxin pathways.Competing Interest StatementThe authors have declared no competing interest.