eATP, Plant Hormones, and Root Hair Growth

1
eATP, Plant Hormones, and Root Hair Growth

• Discovery Lab Lecture
• March 29, 2007

2
Auxin is a Growth-Altering Hormone that is needed
for Normal Root Hair Growth

• Low auxin promotes root growth
• High auxin inhibits root growth, probably by
  promoting the production of ethylene, which
  inhibits root growth
• All we know about auxin effects on root hair
  growth is that it is needed for normal root hair
  growth.

3
Recent publication suggests root hair growth is
affected by auxin availability
Figure taken from Lee Cho (2006) Plant Cell 18
1604-1616
4
eATP can block IAA export and induce IAA build-up
in cap
Note Stain indirectly measures where IAA is
concentrated
5
Logic of possible experiment

• If eADP and apyrase inhibitors inhibit root hair
  growth by inhibiting transport of IAA to regions
  where root hairs grow, then application of IAA
  may be able to reverse inhibitory effects of eATP
  and of apyrase inhibitors on root hair growth.