
The Arabidopsis Diacylglycerol Kinase 4 is involved in nitric oxide-dependent pollen tube guidance and fertilization
Author(s) -
Aloysius Wong,
Lara Donaldson,
Maria Teresa Portes,
Jörg Eppinger,
José A. Feijó,
Chris Gehring
Publication year - 2020
Publication title -
development
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.754
H-Index - 325
eISSN - 1477-9129
pISSN - 0950-1991
DOI - 10.1242/dev.183715
Subject(s) - biology , pollen tube , diacylglycerol kinase , microbiology and biotechnology , arabidopsis , cell signaling , signal transduction , nitric oxide , protein kinase a , biochemistry , kinase , protein kinase c , pollen , botany , mutant , pollination , gene , endocrinology
Nitric oxide (NO) is a key signaling molecule that regulates diverse biological processes in both animals and plants including important roles in male gamete physiology. In plants, NO is generated in pollen tubes (PTs) and affects intracellular responses through the modulation of Ca2+ signaling, actin organization, vesicle trafficking and cell wall deposition bearing consequences in pollen-stigma interactions and PT guidance. In contrast, the NO-responsive proteins that mediate these responses remains elusive. Here we show that PTs of Arabidopsis thaliana impaired in the pollen- specific Diacylglycerol Kinase 4 (DGK4) grow slower and become insensitive to NO-dependent growth inhibition and re-orientation responses. Recombinant DGK4 protein yields NO-responsive spectral and catalytic changes in vitro which are compatible with a role in NO perception and signaling in PTs. In addition to the expected phosphatidic acid producing kinase activity, DGK4 recombinant protein also revealed guanylyl cyclase activity as hinted by sequence analysis. Our results are compatible with a role for the fast-diffusible NO gas in signaling and cell-cell communication via the modulation of DGK4 activity during the progamic phase of angiosperm reproduction.