Reference "A Novel Nuclear-Localized CCCH-Type Zinc Finger Protein, OsDOS, Is Involved in Delaying Leaf Senescence in Rice (Oryza sativa L.)"

Reference ID

11145

Title

A Novel Nuclear-Localized CCCH-Type Zinc Finger Protein, OsDOS, Is Involved in Delaying Leaf Senescence in Rice (Oryza sativa L.)

Source

Plant physiology, 2006, vol. , pp. -

Authors (5)

Kong-Z	Li-M
Yang-W	Xu-W
Xue-Y

Abstract

Leaf senescence is a developmentally programmed degeneration process, which is
fine-tuned by a complex regulatory network for plant fitness. However,
molecular regulation of leaf senescence is poorly understood, especially in
rice (Oryza sativa L.), an important staple crop for more than half of the
world population. Here, we report a novel nuclear-localized CCCH-type zinc
finger protein, OsDOS, involved in delaying leaf senescence in rice. The
expression of OsDOS was down-regulated during natural leaf senescence, panicle
development and pollination, although its transcripts were accumulated in
various organs. RNAi knockdown of OsDOS caused an accelerated age-dependent
leaf senescence, whereas its overexpression produced a marked delay of leaf
senescence, suggesting that it acts as a negative regulator for leaf
senescence. A genome-wide expression analysis further confirmed its negative
regulation for leaf senescence and revealed that, in particular, the jasmonate
(JA) pathway was found to be hyperactive in the OsDOS RNAi transgenic lines but
impaired in the OsDOS overexpressing transgenic lines, indicating that this
pathway is likely involved in the OsDOS-mediated delaying of leaf senescence.
Furthermore, methyl jasmonate (MeJA) treatments of both seeds and detached
leaves from the RNAi and the overexpressing transgenic lines showed hyper- and
hypo-responses, respectively, consistent with the negative regulation of the JA
pathway by OsDOS. Together, these results indicate that OsDOS is a novel
nuclear protein that delays leaf senescence likely, at least in part, by
integrating developmental cues to the JA pathway.