NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Gravity-regulated differential auxin transport from columella to lateral root cap cellsGravity-induced root curvature has long been considered to be regulated by differential distribution of the plant hormone auxin. However, the cells establishing these gradients, and the transport mechanisms involved, remain to be identified. Here, we describe a GFP-based auxin biosensor to monitor auxin during Arabidopsis root gravitropism at cellular resolution. We identify elevated auxin levels at the root apex in columella cells, the site of gravity perception, and an asymmetric auxin flux from these cells to the lateral root cap (LRC) and toward the elongation zone after gravistimulation. We differentiate between an efflux-dependent lateral auxin transport from columella to LRC cells, and an efflux- and influx-dependent basipetal transport from the LRC to the elongation zone. We further demonstrate that endogenous gravitropic auxin gradients develop even in the presence of an exogenous source of auxin. Live-cell auxin imaging provides unprecedented insights into gravity-regulated auxin flux at cellular resolution, and strongly suggests that this flux is a prerequisite for root gravitropism.
Document ID
20040087832
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Ottenschlager, Iris
(Universitat Freiburg D-79014 Freiburg, Germany)
Wolff, Patricia
Wolverton, Chris
Bhalerao, Rishikesh P.
Sandberg, Goran
Ishikawa, Hideo
Evans, Mike
Palme, Klaus
Date Acquired
August 21, 2013
Publication Date
March 4, 2003
Publication Information
Publication: Proceedings of the National Academy of Sciences of the United States of America
Volume: 100
Issue: 5
ISSN: 0027-8424
Subject Category
Life Sciences (General)
Distribution Limits
Public
Copyright
Other
Keywords
Non-NASA Center
NASA Discipline Plant Biology

Available Downloads

There are no available downloads for this record.
No Preview Available