First published online May 17, 2004
Development 131, 1105e (2004)
© The Company of Biologists Limited
NO cue for pollen tubes
When a pollen grain lands on the female reproductive organ of a compatible
plant, it forms a pollen tube that grows through this complex structure to
deposit male gametes in the ovary. Prado and colleagues report on
p. 2707 that nitric
oxide (NO) is an important negative regulator of pollen tube growth. Working
in vitro with pollen from Easter lilies (Lilium longiflorum), they
show that above a critical concentration, an external point source of NO
causes transient inhibition of pollen tube growth followed by reorientation of
the direction of growth. The researchers provide pharmacological evidence that
this response is mediated through a cGMP pathway. Finally, they identify
peroxisomes, which are normally excluded from the pollen tube tip, as the
organelles that synthesise NO and suggest that endogenous NO production
correlates with the regulation of pollen tube growth.
Related articles in Development:
- Nitric oxide is involved in growth regulation and re-orientation of pollen tubes
- Ana Margarida Prado, D. Marshall Porterfield, and José A. Feijó
Development 2004 131: 2707-2714.
[Abstract]
[Full Text]