Skip to main content

Research Repository

Advanced Search

Lateral root emergence in Arabidopsis is dependent on transcription factor LBD29 regulation of auxin influx carrier LAX3

Porco, Silvana; Larrieu, Antoine; Du, Yujuan; Gaudinier, Allison; Goh, Tatsuaki; Swarup, Kamal; Swarup, Ranjan; Kuempers, Britta; Bishopp, Anthony; Lavenus, Julien; Casimiro, Ilda; Hill, Kristine; Benkova, Eva; Fukaki, Hidehiro; Brady, Siobhan M.; Scheres, Ben; Peret, Benjamin; Bennett, Malcolm J.


Silvana Porco

Antoine Larrieu

Yujuan Du

Allison Gaudinier

Tatsuaki Goh

Kamal Swarup

Britta Kuempers

Julien Lavenus

Ilda Casimiro

Kristine Hill

Eva Benkova

Hidehiro Fukaki

Siobhan M. Brady

Ben Scheres

Benjamin Peret


Lateral root primordia (LRP) originate from pericycle stem cells located deep within parental root tissues. LRP emerge through overlying root tissues by inducing auxin-dependent cell separation and hydraulic changes in adjacent cells. The auxin-inducible auxin influx carrier LAX3 plays a key role concentrating this signal in cells overlying LRP. Delimiting LAX3 expression to two adjacent cell files overlying new LRP is crucial to ensure that auxin-regulated cell separation occurs solely along their shared walls. Multiscale modeling has predicted that this highly focused pattern of expression requires auxin to sequentially induce auxin efflux and influx carriers PIN3 and LAX3, respectively. Consistent with model predictions, we report that auxin-inducible LAX3 expression is regulated indirectly by AUXIN RESPONSE FACTOR 7 (ARF7). Yeast one-hybrid screens revealed that the LAX3 promoter is bound by the transcription factor LBD29, which is a direct target for regulation by ARF7. Disrupting auxin-inducible LBD29 expression or expressing an LBD29-SRDX transcriptional repressor phenocopied the lax3 mutant, resulting in delayed lateral root emergence. We conclude that sequential LBD29 and LAX3 induction by auxin is required to coordinate cell separation and organ emergence.


Porco, S., Larrieu, A., Du, Y., Gaudinier, A., Goh, T., Swarup, K., …Bennett, M. J. (2016). Lateral root emergence in Arabidopsis is dependent on transcription factor LBD29 regulation of auxin influx carrier LAX3. Development, 143(18), 3340-3349.

Journal Article Type Article
Acceptance Date Aug 4, 2016
Online Publication Date Aug 30, 2016
Publication Date Sep 15, 2016
Deposit Date Oct 24, 2016
Publicly Available Date Oct 24, 2016
Journal Development (Cambridge)
Print ISSN 0950-1991
Electronic ISSN 1477-9129
Publisher Company of Biologists
Peer Reviewed Peer Reviewed
Volume 143
Issue 18
Pages 3340-3349
Keywords Arabidopsis; Root development; Lateral root emergence; Auxin; LBD29
Public URL
Publisher URL


You might also like

Downloadable Citations