AC fields of low frequency and amplitude stimulate pollen tube growth possibly via stimulation of the plasma membrane proton pump

Abstract Pollen grains transport the sperm cells through the style tissue via a fast-growing pollen tube to the ovaries where fertilization takes place. Pollen tube growth requires a precisely regulated network of cellular as well as molecular events including the activity of the plasma membrane H+ ATPase, which is known to be regulated by reversible protein phosphorylation and subsequent binding of 14-3-3 isoforms. Immunodetection of the phosphorylated penultimate threonine residue of the pollen plasma membrane H+ ATPase (LilHA1) of Lilium longiflorum pollen revealed a sudden increase in phosphorylation with the start of pollen tube growth. In addition to phosphorylation, pH modulated the binding of 14-3-3 isoforms to the regulatory domain of the H+ ATPase, whereas metabolic components had only small effects on 14-3-3 binding, as tested with in vitro assays using recombinant 14-3-3 isoforms and phosphomimicking substitutions of the threonine residue. Consequently, local H+ influxes and effluxes as well as pH gradients in the pollen tube tip are generated by localized regulation of the H+ ATPase activity rather than by heterogeneous localized distribution in the plasma membrane.

Download Full-text

A plant plasma membrane Ca2+ pump is required for normal pollen tube growth and fertilization

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.0401542101 ◽

2004 ◽

Vol 101 (25) ◽

pp. 9502-9507 ◽

Cited By ~ 185

Author(s):

M. Schiott ◽

S. M. Romanowsky ◽

L. Baekgaard ◽

M. K. Jakobsen ◽

M. G. Palmgren ◽

...

Keyword(s):

Plasma Membrane ◽

Pollen Tube ◽

Pollen Tube Growth ◽

Tube Growth ◽

Normal Pollen ◽

Plant Plasma Membrane

Download Full-text

Comparative proteomic analysis reveals a dynamic pollen plasma membrane protein map and the membrane landscape of receptor-like kinases and transporters important for pollen tube growth and interaction with pistils in rice

BMC Plant Biology ◽

10.1186/s12870-016-0961-7 ◽

2017 ◽

Vol 17 (1) ◽

Cited By ~ 9

Author(s):

Ning Yang ◽

Tai Wang

Keyword(s):

Plasma Membrane ◽

Membrane Protein ◽

Pollen Tube ◽

Pollen Tube Growth ◽

Proteomic Analysis ◽

Tube Growth ◽

Plasma Membrane Protein ◽

Comparative Proteomic Analysis ◽

Protein Map

Download Full-text

The haustorial synergids of Cortaderia (Gramineae) at maturity

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.1981.022 ◽

2014 ◽

Vol 50 (1-2) ◽

pp. 151-160 ◽

Cited By ~ 5

Author(s):

Melva N. Philipson

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Pollen Tube ◽

Pollen Tube Growth ◽

Central Cell ◽

Transfer Cell ◽

Tube Growth ◽

Transport Activity ◽

Cell Cytoplasm ◽

Cortaderia Selloana

The ultrastructure of synergids which extend through the micropyle as haustoria and lie against 'the ovary wall are described in Cortaderia selloana and its Fl hybrid with C. araucana. These haustoria bear typical transfer cell wall invaginations closely associated with the plasma membrane and with mitochondria. Their function seems to be one involved in the absorption and conduction of nutrients to the synergids which are atypical in their highly vacuolate structure, degenerate nuclei and few organelles. The synergids appear to act as repositories of nutrients which are, readily accessible to the central cell by virtue of deep intrusions made into them by the central cell cytoplasm. Enzymatic secretion could also be a function of the distal end of the haustorial synergids, both in facilitating tissue peneration during its outward growth and in directing pollen tube growth. At anfhesis, the haustorium - synergid complex appears to be past its peak of absorption and transport activity, and to be involved in a seeretory or degenerative phase.

Download Full-text