INGEBI   02650
INSTITUTO DE INVESTIGACIONES EN INGENIERIA GENETICA Y BIOLOGIA MOLECULAR "DR. HECTOR N TORRES"
Unidad Ejecutora - UE
artículos
Título:
The Pollen Receptor Kinase LePRK2 Mediates Growth-Promoting Signals and Positively Regulates Pollen Germination and Tube Growth
Autor/es:
DONG ZHANG; DIEGO WENGIER; BIN SHUAI; CAIPING GUI; JORGE MUSCHIETTI; SHEILA MCCORMICK; WEIHUA TANG
Revista:
PLANT PHYSIOLOGY.
Referencias:
Año: 2008
ISSN:
0032-0889
Resumen:
In flowering plants, the process of pollen germination and
tube growth is required for successful fertilization. A pollen receptor kinase
from tomato, LePRK2, has been implicated in signaling during pollen germination
and tube growth as well as in mediating pollen (tube)-pistil communication.
Here we show that reduced expression of LePRK2
affects four aspects of pollen germination and tube growth. First, the percentage
of pollen that germinates is reduced, and the time window for competence to
germinate is also shorter. Second, tube growth rate is reduced, and the
expression level of LePRK2 is correlated with the tube growth
rate. Third, tip-localized superoxide production by pollen tubes can not be
increased by exogenous calcium ions. Fourth, pollen tubes have defects in
responses to STIL, an extracellular growth-promoting signal from the pistil. Transient
overexpression of LePRK2-fluorescent protein fusions gave slightly wider pollen
tube tips, whereas pollen tube length was not affected. Together these results
show that LePRK2 positively regulates pollen germination and tube growth and is
involved in transducing responses to extracellular growth-promoting signals.